JP2010184568A - Steering device for vehicle and method for steering vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a steering device for a vehicle and a method of steering the vehicle preventing bias traveling of the vehicle with high accuracy. <P>SOLUTION: Bias traveling prevention control is carried out in which a steering system is provided with bias traveling prevention steering auxiliary torque in the direction canceling steering torque Tp at the time of traveling straightforwardly based on a history of the steering torque Tp when the straightforward traveling condition of the vehicle is detected. At this time, when the difference ¾T-ϕ¾ between a steering torque T and yaw rate ϕ is at or above a predetermined threshold value TH1, a vehicle behavior is determined to be behind with respect to the steering of the steering wheel. In this case, the straightforward traveling condition of the vehicle is set undetected, and the steering torque Tp at this time is not included in the above history. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention belongs to the technical field of a vehicle steering apparatus that performs single flow suppression control for suppressing single flow of a vehicle.

  Conventional vehicle steering devices estimate all inputs such as crosswind, road surface cant, and rough road steering as dynamic disturbances, and control steering assist force so as to compensate for all the estimated disturbances (for example, patents) Reference 1).

JP 2001-1923 A

By the way, the single flow of the vehicle includes a steady disturbance caused by the vehicle and a disturbance caused by a cross wind or the like. However, in this vehicle steering apparatus, since these are confused to solve, the system becomes complicated.
Therefore, it is determined whether or not the vehicle is in a straight traveling state based on vehicle behavior information (for example, yaw rate), and the vehicle travels straight based on the history of steering torque when the vehicle is determined to be in the straight traveling state. A method of applying a single flow restraining steering assist force in a direction to cancel the steering torque at the time can be considered.

However, the vehicle behavior information (for example, the yaw rate) has a delay with respect to the steering torque. Therefore, when the driver steers sharply and greatly from the straight traveling state, a situation occurs in which it is determined that the vehicle is in the straight traveling state even though a large steering torque is generated by the driver's intention.
Therefore, in the above method, the steering torque in such a state is also recorded as a history. As a result, the effect of suppressing the single flow may not be sufficiently obtained.
Therefore, an object of the present invention is to provide a vehicle steering device and a vehicle steering method that can accurately suppress a single flow caused by a vehicle.

  In order to solve the above-described problem, the vehicle steering apparatus according to the present invention is a single-flow suppression control unit that cancels the steering torque during straight traveling based on the history of steering torque in the straight traveling state of the vehicle. A single flow suppression steering assist torque is applied to the steering unit. At this time, when a state in which the vehicle behavior is delayed with respect to steering of the steered wheels is detected, the straight traveling state of the vehicle is not detected.

  According to the present invention, when the vehicle behavior is greatly delayed with respect to the steering wheel steering, the steering torque at that time is not recorded as a history. Thereby, the single flow suppression steering assist torque can be applied based only on the steering torque for maintaining the straight traveling. Therefore, the accuracy of the single flow suppression can be improved.

1 is a schematic configuration diagram of a vehicle steering apparatus according to a first embodiment. It is a flowchart which shows the single flow suppression control processing procedure performed with the controller in 1st Embodiment. It is a figure which shows the relationship between the steering torque at the time of sudden steering, and a yaw rate. It is a figure which shows the difference of the steering torque at the time of sudden steering, and a yaw rate. It is a figure for demonstrating the effect of this invention. It is a flowchart which shows the single flow suppression control processing procedure performed with the controller in 2nd Embodiment. It is a flowchart which shows the single flow suppression control processing procedure performed with the controller in 3rd Embodiment. It is a schematic block diagram of the steering apparatus for vehicles in 4th Embodiment. It is a flowchart which shows the single flow suppression control processing procedure performed with the controller in 4th Embodiment. It is a flowchart which shows the single flow suppression control processing procedure performed with the controller in 5th Embodiment.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
<< First Embodiment >>
"Constitution"
FIG. 1 is a diagram showing a configuration of a vehicle steering apparatus according to a first embodiment of the present invention.
The vehicle steering apparatus includes a steering wheel 1 operated by a driver, and a steering mechanism 3 that steers a front wheel (steering wheel) 2 in accordance with an operation amount of the steering wheel 1.
A steering shaft (steering column) 4 is integrally coupled to the steering wheel 1. A torque sensor 5 and a speed reducer 6 are provided on the steering shaft 4. In addition, a motor 7 is connected via a speed reducer 6.

A pinion 8 of a rack and pinion mechanism is connected to the tip of the steering shaft 4. The knuckle arms of the left and right front wheels 2 are connected to both ends of the rack 9 that can mesh with the pinion 8 and reciprocate in the vehicle width direction via tie rods 10, respectively.
The controller 11 inputs information from the torque sensor 5, the yaw rate sensor 12, and the vehicle speed sensor 13. Based on these pieces of information, a steering assist force that assists the driver's steering force is generated. Further, the motor 7 is driven by a command value corresponding to the steering assist force. In this way, steering assist control is performed.

Further, the controller 11 stores a steering torque (pinion shaft torque) when the vehicle is traveling straight in a memory (not shown) based on various input information, and calculates an average value of the history of the memory. Then, the single flow suppression control is performed in which the calculated value is added to the steering assist force command value as a torque necessary for the single flow suppression.
In this embodiment, when the vehicle behavior is delayed with respect to steering of the steered wheels, the steering torque at that time is not recorded as a history. Here, a state in which the vehicle behavior is delayed with respect to steering of the steered wheels is detected by detecting a state in which the yaw rate is delayed with respect to the steering torque.
Since the vehicle steering apparatus shown in FIG. 1 has a configuration in which a steering unit and a steering unit are mechanically connected, the steering torque and the steering torque are equivalent. Therefore, in this embodiment, the steering torque and the yaw rate are used to detect a state in which the yaw rate is delayed with respect to the steering torque.

(Single flow suppression control processing procedure)
Next, the single flow suppression control processing procedure executed by the controller 11 will be described.
FIG. 2 is a flowchart showing the single flow suppression control processing procedure executed by the controller 11. This single flow suppression control process is repeatedly executed at a predetermined control cycle during traveling (when the vehicle speed sensor 13 detects vehicle speed ≠ 0).
First, in step S1, the controller 11 reads signals from various sensors. Specifically, the steering torque T detected by the torque sensor 5, the yaw rate φ detected by the yaw rate sensor 12, and the motor current command value I of the motor 7 are acquired.

Next, in step S2, the controller 11 determines whether or not the vehicle is traveling straight. Here, it is determined whether or not the absolute value | φ | of the yaw rate read in step S1 is smaller than the yaw rate threshold φth (for example, 2 deg / s). If | φ | <φth, it is determined that the vehicle is traveling straight, and the process proceeds to step S3. On the other hand, when | φ | ≧ φth, the routine proceeds to step S6 described later.
In step S3, the controller 11 determines whether or not the absolute value | T−φ | of the difference between the steering torque T read in step S1 and the yaw rate φ is equal to or greater than a threshold value TH1 (for example, 4). When | T−φ | <TH1, the process proceeds to step S4. When | T−φ | ≧ TH1, the process proceeds to step S6 described later.

In step S4, the controller 11 calculates a turning torque (pinion shaft rotation torque) Tp. Here, based on the steering torque T and the motor current command value I read in step S1, the turning torque Tp is calculated based on the following equation.
Tp = T + K _M × I (1)
Here, K _M is a coefficient for converting the motor current command value I to the steering assist torque.
In addition, when temperature dependence, speed dependence characteristics, etc. are strong, the steering torque Tp is calculated using a map.

Next, in step S5, the controller 11 records the steering torque Tp calculated in step S4 in the memory, and proceeds to step S6.
In step S6, the controller 11 calculates the average value of the history of the steering torque Tp stored in the memory, and proceeds to step S7. As the average value of the history calculated here, history data of a sufficiently long time is used so that the influence of instantaneous input due to disturbance or the like can be relatively ignored.

In step S7, the controller 11 drives the motor 7 using the average value of the history calculated in step S6 as a torque (single flow suppression steering assist torque) necessary for single flow suppression, and ends the single flow suppression control process.
Here, the calculated value of the single flow suppression steering assist torque is calculated independently of the steering assist force generated by the steering assist control. When there is a command value by steering assist control, the calculated value is always added as a steady offset on the command value.

  In this way, the straight traveling state of the vehicle is determined based on the yaw rate φ as the vehicle behavior information, and the turning torque Tp when it is determined that the vehicle is traveling straight is recorded in the memory. At this time, when the difference | T−φ | between the steering torque T and the yaw rate φ is equal to or greater than the threshold value TH1, the turning torque Tp at that time is not recorded in the memory. The controller 11 calculates the average value of the turning torque Tp recorded in the memory, and drives the motor 7 using this as a torque necessary for one-way suppression.

<Operation>
Next, the operation of the first embodiment will be described.
Assume that the host vehicle is traveling straight ahead. In this case, the yaw rate φ detected by the yaw rate sensor 12 is smaller than the yaw rate threshold φth. Therefore, it determines with Yes by step S2 of FIG. 2, and transfers to step S3. At this time, it is assumed that there is no delay in vehicle behavior information (yaw rate φ) with respect to the steering torque T. In that case, the difference | T−φ | between the steering torque T and the yaw rate φ is smaller than the threshold value TH1. Therefore, it determines with No by step S3, transfers to step S4, and records steering torque Tp (steering torque + steering assist torque) at this time in memory. The above processing is repeated while | φ | <φth and | T−φ | <TH1.

  In step S6, the average value of the history of the turning torque Tp recorded in the memory is calculated. The calculated value is added to the steering assist force as a single flow suppression steering assist torque. In this way, the steering assist force is offset using the average value of the steering torque Tp in the straight traveling state as the one-flow suppression steering assist torque. As a result, in a vehicle in which a steady single flow is generated, torque generated by the single flow can be suppressed without interfering with the steering assist control.

It is assumed that the driver has steered greatly from this straight traveling state.
FIG. 3 is a diagram showing the relationship between the steering torque T and the yaw rate φ during sudden steering.
When the driver steers greatly from the straight traveling state (area A), first, a large steering torque T is generated, and then a yaw rate φ is generated with a predetermined delay.
Incidentally, as a method for determining whether or not the vehicle is traveling straight, it is common to employ a method for determining whether or not the yaw rate φ is smaller than a predetermined yaw rate threshold φth. However, in this general straight traveling determination, it is erroneously determined that the vehicle is in a straight traveling state in the region B where the yaw rate φ is delayed. Therefore, in the case of a system that determines the one-flow restraint steering assist torque based on the history of the steering torque T during the straight traveling state, the history includes the steering torque T in a region that is not in the original straight traveling state. As a result, the single flow suppression accuracy is reduced.
On the other hand, in this embodiment, even when the yaw rate φ is smaller than the predetermined yaw rate threshold φth, if | T−φ | ≧ TH1, the process proceeds from step S3 to step S6. That is, the turning torque Tp at that time is not recorded as a history.

FIG. 4 is a diagram showing the difference between the steering torque T and the yaw rate φ during sudden steering.
As shown in FIG. 4, when the driver suddenly steers, the yaw rate φ is delayed with respect to the steering torque T, so that the difference C between the steering torque T and the yaw rate φ is greater than or equal to the threshold value TH1. Exists. In the present embodiment, in this region C, it is determined that the vehicle is not in a straight traveling state, and the turning torque Tp at that time is not recorded in the memory as a history.
In this way, erroneous determination of the straight traveling state in the region B that is not the original straight traveling state can be suppressed. As a result, it is possible to suppress application of an excessive / underly small single-flow restraining steering assist torque that maintains straight travel.

FIG. 5 is a diagram for explaining the effect of the present invention.
FIG. 5A shows a state of the steering torque T and the yaw rate φ when the driver continuously steers. FIG. 5B shows a torque history recording state when the above-described general straight-ahead determination is used, and FIG. 5C shows a torque history recording state when the straight-ahead determination according to this embodiment is used. ing.
As can be seen from this figure, in this embodiment, sudden steering is continuously performed, and the erroneous determination (erroneous recording) in the section where the torque at that time is not desired to be recorded as a history is less than in the conventional method. . Therefore, it is possible to determine the single flow suppression steering assist torque with high accuracy.

  In FIG. 1, the torque sensor 5 constitutes a steering torque detection means, and the yaw rate sensor 12 constitutes a yaw rate detection means. 2, step S2 constitutes a straight traveling state determination means, step S3 constitutes a delay state detection means, step S4 constitutes a turning torque detection means, and steps S6 and S7 suppress one-sided flow. It constitutes a control means.

"effect"
(1) The straight traveling state determination means determines whether or not the vehicle is in a straight traveling state based on the vehicle behavior information. The steered torque detecting means detects the steered torque of the steered portion that steers the steered wheels. The single flow suppression control means cancels the turning torque during straight running based on the history of turning torque detected by the turning torque detection means when the straight running state detection means determines that the vehicle is in the straight running state. A single flow suppression steering assist torque is applied to the steering unit. The delay state detection means detects a state in which the vehicle behavior is delayed with respect to steering of the steered wheels. The straight traveling state determining means determines that the vehicle is in the non-straight traveling state when the delayed state detecting means detects a state in which the vehicle behavior is delayed with respect to the steering wheel steering.

In this way, dynamic correction is not performed every moment, but the vehicle characteristic itself is steadily steering assist controlled using a long-term history. Therefore, simplification of the system and stable suppression of the single flow caused by the vehicle can be realized.
In addition, the single-flow suppression steering assist force is controlled independently of other steering assist controls, and the single-flow suppression steering assist torque is constantly added to (or subtracted from) the steering assist torque. Therefore, even when a plurality of controls are performed, control interference does not occur. Therefore, the single flow caused by the vehicle can be suppressed without causing erroneous assist or deterioration of the steering feeling.

Furthermore, even if it is determined that the vehicle is in the straight traveling state based on the vehicle behavior information, it is determined that the vehicle is not in the straight traveling state when the steering torque is greatly generated by the driver's intention. Therefore, it is possible not to use the turning torque at that time for calculation of the single flow suppression steering assist torque.
As described above, when a state in which the vehicle behavior is delayed with respect to steering of the steered wheels is detected, the steering torque at that time is not recorded as a history. Thereby, the single flow suppression steering assist torque can be applied based only on the steering torque for maintaining the straight traveling. As a result, the accuracy of the single flow suppression can be improved.

(2) When the difference between the turning torque detected by the turning torque detecting means and the yaw rate detected by the yaw rate detecting means is equal to or greater than a predetermined difference threshold, the delay state detecting means It is determined that the vehicle behavior is delayed.
As a result, when the generation of the yaw rate is delayed with respect to the generation of the steering torque (steering torque), such as when the driver performs a large sudden steering, it is erroneously determined that the vehicle is in a straight traveling state. Can be suppressed.

(3) With the vehicle behavior following the steering of the steered wheels without delay, the steering torque during straight traveling is calculated based on the steering torque history when the vehicle is traveling straight ahead. A single flow restraining steering assist torque is applied in the direction of cancellation.
Thereby, the suppression of the single flow caused by the vehicle can be performed with high accuracy.

<< Second Embodiment >>
Next, a second embodiment of the present invention will be described.
In the second embodiment, the delay of the yaw rate φ with respect to the steering torque T is efficiently detected by correcting the level of the magnitude of the steering torque T and the yaw rate φ.
"Constitution"
The overall configuration of the vehicle steering apparatus in the second embodiment is the same as that of the first embodiment described above shown in FIG.
(Single flow suppression control processing procedure)
The single flow suppression control processing procedure executed by the controller 11 of the second embodiment will be described.

  FIG. 6 is a flowchart showing a single flow suppression control processing procedure executed by the controller 11 of the second embodiment. This single flow suppression control process is the same as that in FIG. 2 except that step S3 is replaced with steps S11 and S12 in the single flow suppression control process shown in FIG. Accordingly, parts corresponding to those in FIG.

In step S11, the controller 11 corrects the steering torque T and the yaw rate φ so that the levels of the steering torque T and the yaw rate φ are equal. Specifically, the steering torque correction value T ′ is calculated by multiplying the steering torque T read in step S1 by the gain K1. Further, the yaw rate correction value φ ′ is calculated by multiplying the yaw rate φ read in step S1 by the gain K2.
T ′ = T × K1 (2)
φ ′ = φ × K2 (3)
Here, the gains K1 and K2 are tuned in advance so as to eliminate the difference in level between the steering torque T and the yaw rate φ and extract only the delay of the yaw rate φ with respect to the steering torque T.

Next, in step S12, the controller 11 determines whether or not the absolute value | T′−φ ′ | of the difference between the steering torque correction value T ′ calculated in step S11 and the yaw rate correction value φ ′ is equal to or greater than the threshold value TH2. Determine. When | T′−φ ′ | <TH2, the process proceeds to step S4. When | T′−φ ′ | ≧ TH2, the process proceeds to step S6.
In the process of FIG. 6, step S11 constitutes a correction value calculation means, and step S12 constitutes a delay state detection means.

"effect"
(4) The correction value calculation means converts the turning torque detected by the turning torque detection means and the yaw rate detected by the yaw rate detection means, and the turning torque correction value and the yaw rate correction obtained by combining both magnitude levels. Calculate the value. When the difference between the turning torque correction value calculated by the correction value calculation means and the yaw rate correction value is equal to or greater than a predetermined difference threshold, the delay state detection means is delayed in vehicle behavior with respect to steering of the steered wheels. Judged to be in a state.
Thereby, the level of the magnitude | size of steering torque (steering torque) and a yaw rate can be match | combined. Therefore, it is possible to eliminate the influence of the difference due to the difference in the size level. Therefore, it is possible to accurately detect the delay of the yaw rate with respect to the steering torque (steering torque).

<< Third Embodiment >>
Next, a third embodiment of the present invention will be described.
In the third embodiment, the delay of the yaw rate φ with respect to the steering torque T is detected based on the ratio of the yaw rate φ with respect to the steering torque T.
"Constitution"
The overall configuration of the vehicle steering apparatus in the third embodiment is the same as that of the first embodiment described above shown in FIG.

(Single flow suppression control processing procedure)
The single flow suppression control processing procedure executed by the controller 11 of the third embodiment will be described.
FIG. 7 is a flowchart showing a single flow suppression control processing procedure executed by the controller 11 of the third embodiment. This single flow suppression control process is the same as that in FIG. 2 except that step S3 is replaced with step S21 in the single flow suppression control process shown in FIG. Accordingly, parts corresponding to those in FIG.

In step S21, the controller 11 determines whether or not the absolute value | φ / T | of the ratio of the yaw rate φ to the steering torque T read in step S1 is greater than or equal to a threshold value TH3. When | φ / T | <TH3, the process proceeds to step S4. When | φ / T | ≧ TH3, the process proceeds to step S6.
In the process of FIG. 7, step S21 constitutes a delay state detecting means.

"effect"
(5) When the ratio of the yaw rate detected by the yaw rate detection means to the steering torque detected by the steering torque detection means is equal to or greater than a predetermined ratio threshold, the delay state detection means Judge that the behavior is delayed.
Thereby, even if the level of the magnitude of the steering torque (steering torque) and the yaw rate are different, the delay of the yaw rate with respect to the steering torque (steering torque) can be detected with high accuracy.

<< Fourth Embodiment >>
Next, a fourth embodiment of the present invention will be described.
In the fourth embodiment, a delay in vehicle behavior with respect to steering of steered wheels is detected based on a driver's steering angular velocity ω.
"Constitution"
FIG. 8 is a diagram illustrating an overall configuration of a vehicle steering apparatus according to the fourth embodiment. This vehicle steering device is the same as that shown in FIG. 1 except that in the vehicle steering device in the first to third embodiments shown in FIG. 1, an encoder 14 for detecting the steering angle θ is connected to the motor 7. It has the composition of.

(Single flow suppression control processing procedure)
The single flow suppression control processing procedure executed by the controller 11 of the fourth embodiment will be described.
FIG. 9 is a flowchart illustrating a single flow suppression control processing procedure executed by the controller 11 of the fourth embodiment. This single flow suppression control process is the same as that in FIG. 2 except that step S3 is replaced with step S31 in the single flow suppression control process shown in FIG. Accordingly, parts corresponding to those in FIG.

In step S31, the controller 11 reads the steering angle θ measured by the encoder 14, and calculates the steering angular velocity ω by time differentiating the steering angle θ. Then, it is determined whether or not the calculated absolute value | ω | of the steering angular velocity is greater than or equal to a threshold value TH4. When | ω | <TH4, the process proceeds to step S4. When | ω | ≧ TH4, the process proceeds to step S6.
In FIG. 8, the encoder 14 constitutes a turning angular velocity detection means. Further, in the processing of FIG. 9, step S31 constitutes a delay state detecting means.

"effect"
(6) The delay state detection means is a state in which the vehicle behavior is delayed with respect to the steered wheel turning when the turning angular speed detected by the turning angular speed detection means is equal to or greater than a predetermined turning angular speed threshold. Judge.
As a result, it is possible to detect a state in which the driver is steering rapidly. Therefore, it is possible to detect a delay in vehicle behavior with respect to steering of steered wheels, which occurs due to the driver's sudden steering.

<< Fifth Embodiment >>
Next, a fifth embodiment of the present invention will be described.
In the fifth embodiment, a delay in vehicle behavior relative to steering of steered wheels is detected based on the steering angular velocity ω and steering torque T of the driver.
"Constitution"
The overall configuration of the vehicle steering apparatus in the fifth embodiment is the same as that of the fourth embodiment described above shown in FIG.

(Single flow suppression control processing procedure)
The single flow suppression control processing procedure executed by the controller 11 of the fifth embodiment will be described.
FIG. 10 is a flowchart illustrating a single flow suppression control processing procedure executed by the controller 11 of the fifth embodiment. This single flow suppression control process is the same as that of FIG. 9 except that step S31 is replaced with step S41 in the single flow suppression control process shown in FIG. Accordingly, parts corresponding to those in FIG.

In step S41, the controller 11 calculates the steering angular velocity ω by reading the steering angle θ measured by the encoder 14 and performing time differentiation on the steering angle θ. Then, it is determined whether or not the calculated absolute value | ω | of the steering angular velocity is greater than or equal to the threshold value TH4 and the absolute value | T | of the steering torque read in step S1 is greater than or equal to the threshold value TH5. If | ω | <TH4 or | T | <TH5, the process proceeds to step S4. On the other hand, when | ω | ≧ TH4 and | T | ≧ TH5, the routine proceeds to step S6.
In the process of FIG. 10, step S41 constitutes a delay state detecting means.

"effect"
(7) The delay state detecting means is such that the turning angular speed detected by the turning angular speed detecting means is not less than a predetermined turning angular speed threshold, and the turning torque detected by the turning torque detecting means is not less than a predetermined turning torque threshold. When it is, it is determined that the vehicle behavior is delayed with respect to the steering wheel steering.
As a result, it is possible to detect a state in which the driver is performing large sudden steering. Therefore, it is possible to detect a delay in the vehicle behavior with respect to the steering of the steered wheels, which is caused by the driver's large sudden steering.

<Modification>
(1) In the above embodiments, examples of front wheel steering assist using EPS (Electric Power Steering) have been shown. However, vehicle steering such as DYC using braking / driving force, left / right independent control of each wheel, and rear wheel steering can be performed. It can be applied to other possible systems.
(2) In each of the above embodiments, the case where the present invention is applied to a system in which a steering unit and a steered unit are mechanically connected has been described. However, for example, the present invention may be applied to a steer-by-wire system. it can. In this case, a steering reaction force corresponding to the single flow suppression steering assist torque calculated based on the steering torque history in the straight traveling state is applied to the steering system.

(3) In the above embodiments, the case where the yaw rate φ of the vehicle is detected using the yaw rate sensor 12 has been described. However, the yaw rate φ of the vehicle is detected based on the difference between the left and right wheel speeds detected by the wheel speed sensor or the like. You can also
(4) In each of the above embodiments, it is possible to determine whether the vehicle is traveling straight in combination with the steering torque speed or the yaw angular acceleration. Thereby, the straight running state of the vehicle can be detected with higher accuracy.

DESCRIPTION OF SYMBOLS 1 Steering wheel 2 Front wheel 3 Steering mechanism 4 Steering shaft 5 Torque sensor 6 Reducer 7 Motor 8 Pinion 9 Rack 10 Tie rod 11 Controller 12 Yaw rate sensor 13 Vehicle speed sensor 14 Encoder

Claims (7)

Based on the vehicle behavior information, straight traveling state determining means for determining whether or not the vehicle is traveling straight;
Steered torque detecting means for detecting the steered torque of the steered portion that steers steered wheels;
One-flow restraint steering assist that cancels the steering torque during straight traveling based on the history of the steering torque detected by the steering torque detection means when the straight traveling state determination means determines that the vehicle is in a straight traveling state A single flow suppression control means for applying torque to the steering section;
Delay state detecting means for detecting a state in which the vehicle behavior is delayed with respect to the steering of the steering wheel,
The straight traveling state determining means determines that the vehicle is in a non-straight traveling state when the delay state detecting means detects a state in which the vehicle behavior is delayed with respect to steering of the steered wheels. A vehicle steering device. It further comprises a yaw rate detection means for detecting the yaw rate of the vehicle,
When the difference between the steering torque detected by the steering torque detection means and the yaw rate detected by the yaw rate detection means is equal to or greater than a predetermined difference threshold, the delay state detection means The vehicle steering apparatus according to claim 1, wherein the vehicle behavior is determined to be delayed. Yaw rate detection means for detecting the yaw rate of the vehicle;
Correction value calculation for converting the turning torque detected by the turning torque detection means and the yaw rate detected by the yaw rate detection means, and calculating the turning torque correction value and the yaw rate correction value in which both levels are combined And further comprising means,
When the difference between the steering torque correction value calculated by the correction value calculation means and the yaw rate correction value is equal to or greater than a predetermined difference threshold, the delay state detection means delays the vehicle behavior relative to steering of the steered wheels. The vehicle steering apparatus according to claim 1, wherein the vehicle steering apparatus is determined to be in a closed state. It further comprises a yaw rate detection means for detecting the yaw rate of the vehicle,
When the ratio of the yaw rate detected by the yaw rate detection means to the steering torque detected by the steering torque detection means is equal to or greater than a predetermined ratio threshold, the delay state detection means The vehicle steering apparatus according to claim 1, wherein it is determined that the behavior is delayed. A steering angular velocity detecting means for detecting a steering angular velocity of the steering unit;
The delay state detection means is a state in which the vehicle behavior is delayed with respect to steering of steered wheels when the turning angular speed detected by the turning angular speed detection means is equal to or greater than a predetermined turning angular speed threshold. The vehicle steering apparatus according to claim 1, wherein the determination is made. A steering angular velocity detecting means for detecting a steering angular velocity of the steering unit;
The delay state detecting means has a turning angular speed detected by the turning angular speed detecting means that is equal to or greater than a predetermined turning angular speed threshold, and a turning torque detected by the turning torque detecting means is equal to or greater than a predetermined turning torque threshold. The vehicle steering apparatus according to claim 1, wherein the vehicle behavior is determined to be delayed with respect to the steering wheel steering.   In a state where the vehicle behavior follows the steering of the steered wheel without delay, the steering torque in the direction of canceling the steering torque during straight traveling is based on the history of the steering torque when the vehicle is traveling straight ahead. A vehicular steering method, wherein a single flow suppression steering assist torque is applied to a steering unit.

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