JP7180574B2 - Steering control device and steering control method - Google Patents

Description

The present invention relates to a steering control device and a steering control method.

Conventionally, the steering of the own vehicle is controlled so that the own vehicle follows a preceding vehicle traveling in front of the own vehicle. For example, Patent Literature 1 discloses performing steering control of the own vehicle based on the position information of the preceding vehicle.

JP-A-2005-332192

When the own vehicle is a large vehicle such as a truck, it may travel following a small vehicle such as a passenger car. A small vehicle has a higher degree of lateral freedom in a lane than a large vehicle. Therefore, when a large vehicle runs following a small vehicle, the frequency of lateral movement increases, and there is a possibility that the running becomes unstable.

Accordingly, the present invention has been made in view of these points, and an object of the present invention is to provide a steering control device and a steering control method that enable a vehicle to travel stably.

A steering control device according to a first aspect of the present invention is a steering control device that performs steering control of a vehicle, and specifies a vehicle width of the vehicle and a vehicle width of a preceding vehicle running in front of the vehicle. a vehicle width specifying unit, a displacement amount specifying unit that specifies a displacement amount that is a distance from a center position of a lane in which the vehicle travels to a predetermined position of the preceding vehicle, and a vehicle width of the preceding vehicle that is the same as that of the vehicle. width, the displacement amount specified by the displacement amount specifying unit is less than a first threshold value set based on a value that is half the difference between the vehicle width of the vehicle and the vehicle width of the preceding vehicle. When , the vehicle does not perform steering control so that the vehicle runs following the preceding vehicle, and the displacement amount specified by the displacement amount specifying unit is equal to or greater than the first threshold value, the vehicle a steering control unit that controls the steering of the vehicle so that it runs following the preceding vehicle.

The steering control device further includes a lane width specifying unit that specifies a lane width of the lane in which the vehicle travels, and the steering control unit controls the width of the preceding vehicle when the width of the preceding vehicle is smaller than that of the vehicle. , when the displacement amount specified by the displacement amount specifying unit is equal to or greater than the first threshold value and less than a second threshold value set based on a value that is half the lane width specified by the lane width specifying unit, Steering control of the vehicle may be performed such that the distance in the vehicle width direction between the vehicle and the preceding vehicle maintains the first threshold value.

When the vehicle width of the preceding vehicle is smaller than the vehicle width of the vehicle, the steering control unit determines that the displacement amount identified by the displacement amount identification unit is the sum of the first threshold value and the second threshold value. is equal to or greater than a third threshold, the steering control may be performed such that a predetermined position of the vehicle in the vehicle width direction coincides with a predetermined position of the preceding vehicle.

When the vehicle width of the preceding vehicle is smaller than the vehicle width of the vehicle, the steering control unit determines that the displacement amount specified by the displacement amount specifying unit is equal to or greater than the second threshold value and the third threshold value. When it is less than the displacement amount, steering control of the vehicle may be performed so that the distance in the vehicle width direction between the vehicle and the preceding vehicle is shortened according to the increase in the displacement amount.

The steering control device may further include a vehicle speed specifying unit that specifies a vehicle speed of the vehicle, and the steering control unit may set the threshold further based on the vehicle speed specified by the vehicle speed specifying unit.

The steering control device further includes an inter-vehicle distance specifying unit that specifies an inter-vehicle distance between the vehicle and the preceding vehicle, and the steering control unit further determines the inter-vehicle distance based on the inter-vehicle distance specified by the inter-vehicle distance specifying unit. A threshold may be set.

A steering control method according to a second aspect of the present invention is a steering control method for performing steering control of a vehicle, wherein a vehicle width of the vehicle and a vehicle width of a preceding vehicle running in front of the vehicle are specified. determining a displacement amount, which is a distance from a center position of the lane in which the vehicle travels in the lane width direction to a predetermined position of the preceding vehicle; and the displacement amount is less than a first threshold value set based on a value that is half the difference between the vehicle width of the vehicle and the vehicle width of the preceding vehicle, the vehicle is less than the preceding vehicle. When the displacement amount is equal to or greater than the first threshold value, steering control of the vehicle is performed so that the vehicle follows the preceding vehicle. performing.

ADVANTAGE OF THE INVENTION According to this invention, it is effective in the behavior of a vehicle being able to be made to run stably.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure for demonstrating the outline|summary of the steering control apparatus which concerns on this embodiment. It is a figure which shows the structure of the steering control apparatus which concerns on this embodiment. FIG. 5 is a diagram showing the relationship between the amount of displacement from the center position of the lane to the position of the preceding vehicle and the amount of displacement in the vehicle width direction between the vehicle and the preceding vehicle during follow-up control by the steering control device; FIG. 4 is a diagram showing the relationship between vehicle speed and gain; 4 is a flowchart showing the flow of processing related to steering control when the vehicle width of the preceding vehicle is smaller than the vehicle width of the vehicle;

[Overview of Steering Control Device 10]
FIG. 1 is a diagram for explaining an outline of a steering control device 10 according to this embodiment. For example, when a large vehicle V1 such as a bus or truck is running in the auto-cruise mode, the steering control device 10 controls the steering of the vehicle V1 so that the vehicle V1 runs in front of the vehicle V1. This is a computer that causes the vehicle to travel following the preceding vehicle V2.

The steering control device 10 specifies the vehicle width W1 of the vehicle V1 and the vehicle width W2 of the preceding vehicle V2, and determines the predetermined position of the preceding vehicle V2 from the center position of the lane in which the vehicle V1 and the preceding vehicle V2 are traveling. A displacement amount D indicating the distance to is specified. Here, it is assumed that the predetermined positions of the vehicle V1 and the preceding vehicle V2 are, for example, the center positions of the vehicle V1 and the preceding vehicle V2 in the vehicle width direction.

When the vehicle width W2 of the preceding vehicle V2 is smaller than the vehicle width W1 of the vehicle V1, the steering control device 10 sets the displacement amount D to half the vehicle width W1 of the vehicle V1 and the vehicle width W2 of the preceding vehicle V2. When it is less than the first threshold set based on the value, control is performed so that the steering control of the vehicle V1 is not performed ((A) in FIG. 1). Further, when the displacement amount D is equal to or greater than the first threshold, the steering control device 10 performs steering control of the vehicle V1 so that the vehicle V1 follows the preceding vehicle V2 ((B) in FIG. 1).

As a result, the steering control device 10 prevents the vehicle V1 from following the preceding vehicle V2 even if the preceding vehicle V2 frequently moves left and right in the vicinity of the center of the lane, and allows the vehicle V1 to run in a stable manner. can be done.
Next, the configuration of the steering control device 10 will be described.

[Structure of steering control device 10]
FIG. 2 is a diagram showing the configuration of the steering control device 10 according to this embodiment.
As shown in FIG. 2, the steering control device 10 is electrically connected to an imaging device 1, a vehicle speed sensor 2, and a motor 3 provided in a vehicle V1.

The imaging device 1 captures an image of the forward direction of the vehicle V1, including the lane on which the vehicle V1 is traveling, at predetermined time intervals (for example, 10 milliseconds). The imaging device 1 outputs the captured image to the steering control device 10 . In addition, in this embodiment, although the vehicle V1 shall be equipped with the imaging device 1, it is not restricted to this. The vehicle V1 may include LiDAR (Light Detection and Ranging) instead of the imaging device 1, or may include both the imaging device 1 and LiDAR.

Vehicle speed sensor 2 detects the vehicle speed of vehicle V1. The vehicle speed sensor 2 outputs vehicle speed information indicating the detected vehicle speed to the steering control device 10 .
The motor 3 is provided on the steering shaft of the vehicle V1. The motor 3 is rotationally driven under the control of the steering control device 10 to apply torque to the steering shaft and perform steering control.

The steering control device 10 includes a storage section 11 and a control section 12 .
The storage unit 11 is, for example, a ROM (Read Only Memory), a RAM (Random Access Memory), or a hard disk. The storage unit 11 stores various programs for causing the control unit 12 to function. Storage unit 11 stores a steering control program that causes control unit 12 to function as vehicle width identification unit 121 , lane width identification unit 122 , displacement amount identification unit 123 , vehicle speed identification unit 124 , and steering control unit 125 .

The control unit 12 is, for example, a CPU (Central Processing Unit). By executing the steering control program stored in the storage unit 11, the control unit 12 controls the vehicle width identification unit 121, the lane width identification unit 122, the displacement amount identification unit 123, the vehicle speed identification unit 124, and the steering control unit 125. function as

The vehicle width specifying unit 121 specifies the vehicle width of the vehicle V1 and the vehicle width of the preceding vehicle V2 traveling in front of the vehicle V1. For example, the storage unit 11 stores information indicating the vehicle width of the vehicle V1. to specify the vehicle width W1. Further, the vehicle width identification unit 121 identifies the vehicle width W2 of the preceding vehicle V2 by analyzing the captured image captured by the imaging device 1 . Note that when the vehicle V1 can perform inter-vehicle communication with the preceding vehicle V2, the vehicle width specifying unit 121 obtains vehicle width information indicating the width W2 of the preceding vehicle V2 from the preceding vehicle V2 through inter-vehicle communication. The vehicle width W2 of the preceding vehicle V2 may be specified by obtaining the width W2.

The lane width specifying unit 122 specifies the lane width of the lane in which the vehicle V1 travels. For example, the lane width identification unit 122 identifies the lane width of the lane in which the vehicle V1 travels by analyzing the positions of the white lines that define the lane and appear in the captured image captured by the imaging device 1 .

The displacement amount specifying unit 123 specifies the displacement amount D, which is the distance from the center position in the vehicle width direction of the lane in which the vehicle V1 and the preceding vehicle V2 travel to a predetermined position of the preceding vehicle V2.

First, when the captured image captured by the imaging device 1 includes a white line on the left side and a white line on the right side of the lane in which the vehicle V1 is traveling, the displacement amount specifying unit 123 determines the lane line based on the positions of these white lines. Identify the center position of

The displacement amount specifying unit 123 determines that one of the white line on the left side and the white line on the right side of the lane in which the vehicle V1 is traveling is not captured in the captured image captured by the imaging device 1, and the center position of the lane is determined based on the captured image. cannot be specified, the first displacement amount, which is the distance from the last specified center position of the lane to the position of the vehicle V1 in the vehicle width direction, is specified. For example, the displacement amount specifying unit 123 specifies the first displacement amount based on the acceleration detected by the acceleration sensor, the captured image captured by the imaging device, or the like.

Further, when the preceding vehicle V2 is shown in the captured image captured by the imaging device 1, the displacement amount specifying unit 123 determines the position of the preceding vehicle V2 in the vehicle width direction based on the position of the vehicle V1 in the vehicle width direction. Then, the relative displacement amount, which is the amount of displacement from the position of the vehicle V1 in the vehicle width direction to the position of the preceding vehicle V2 in the vehicle width direction, is specified.

By adding the first displacement amount and the relative displacement amount, the displacement amount specifying unit 123 determines the distance from the center position in the vehicle width direction of the lane in which the vehicle V1 and the preceding vehicle V2 travel to the position of the preceding vehicle V2. A certain amount of displacement D is specified. Here, it is assumed that the displacement amount D on the right side in the traveling direction takes a positive value, and the displacement amount D on the left side in the traveling direction takes a negative value.

The vehicle speed identification unit 124 identifies the vehicle speed of the vehicle V1 by obtaining vehicle speed information indicating the vehicle speed of the vehicle V1 output from the vehicle speed sensor 2 .

When the vehicle V1 is running in the auto-cruise mode, the steering control unit 125 controls the motor 3 to apply torque to the steering shaft and perform operation control. When the displacement amount specifying unit 123 can specify the center position of the lane, the steering control unit 125 performs steering control so that the vehicle V1 travels in the center position of the lane.

Further, when the displacement amount specifying unit 123 cannot specify the center position of the lane and the preceding vehicle V2 is shown in the captured image, the steering control unit 125 causes the vehicle V1 to follow the preceding vehicle V2. Steering control is performed so as to When the vehicle width of the preceding vehicle V2 is larger than the vehicle width of the vehicle V1, the steering control unit 125 steers the vehicle V1 so that the position thereof in the vehicle width direction coincides with the position of the preceding vehicle V2 in the vehicle width direction. control.

Further, when the vehicle width of the preceding vehicle V2 is smaller than the vehicle width of the vehicle V1, the steering control unit 125 performs different steering control according to the magnitude of the displacement amount D specified by the displacement amount specifying unit 123. , causes the vehicle V1 to follow the preceding vehicle V2. FIG. 3 shows the relationship between the amount of displacement D from the center position of the lane to the position of the preceding vehicle V2 and the amount of displacement Dc in the vehicle width direction between the vehicle V1 and the preceding vehicle V2 during follow-up control by the steering control device 10. It is a diagram. Hereinafter, with reference to FIG. 3, specific processing relating to steering control when the vehicle width of the preceding vehicle V2 is smaller than the vehicle width of the vehicle V1 will be described. In the following description, an example in which the displacement amount D takes a positive value will be used.

First, the steering control unit 125 determines the first threshold value based on the half value of the difference between the vehicle width W1 of the vehicle V1 and the vehicle width W2 of the preceding vehicle V2 and the vehicle speed of the vehicle V1 specified by the vehicle speed specifying unit 124. Set Th1. The first threshold Th1 is a threshold for determining whether or not to perform steering control so that the vehicle V1 follows the preceding vehicle V2. Specifically, the first threshold value Th1 is obtained by multiplying half the difference between the vehicle width W1 of the vehicle V1 and the vehicle width W2 of the preceding vehicle V2 by a gain G determined based on the vehicle speed of the vehicle V1. set by

FIG. 4 is a diagram showing the relationship between the vehicle speed of the vehicle V1 and the gain G. As shown in FIG. As shown in FIG. 4, the gain G is 1 until the vehicle speed reaches a predetermined vehicle speed Vx, and decreases in proportion to the reciprocal of the vehicle speed after the vehicle speed exceeds the predetermined vehicle speed Vx. Note that the gain G may linearly decrease when the vehicle speed exceeds the predetermined vehicle speed Vx. Accordingly, the steering control unit 125 sets the first threshold Th1 such that the higher the vehicle speed, the smaller the first threshold Th1.

In this embodiment, the steering control unit 125 specifies the gain G based on the vehicle speed of the vehicle V1, but the present invention is not limited to this. For example, the steering control unit 125 may specify the gain G based on the inter-vehicle distance between the vehicle V1 and the preceding vehicle V2. In this case, the steering control device 10 includes an inter-vehicle distance specifying unit that specifies the inter-vehicle distance between the vehicle V1 and the preceding vehicle V2.

When the gain G is set based on the inter-vehicle distance, it is 1 until the inter-vehicle distance reaches a predetermined distance, and when the inter-vehicle distance exceeds the predetermined distance, the reciprocal of the inter-vehicle distance is shall decrease in proportion to The gain G may linearly decrease when the inter-vehicle distance exceeds a predetermined distance. Accordingly, the steering control unit 125 sets the first threshold Th1 such that the larger the inter-vehicle distance, the smaller the first threshold Th1.

Moreover, the steering control unit 125 may specify the gain G based on the lane width specified by the lane width specifying unit 122 . For example, the steering control unit 125 may reduce the gain G as the lane width becomes narrower.

The steering control unit 125 determines that the displacement amount D specified by the displacement amount specifying unit 123 is half the difference between the vehicle width W1 of the vehicle V1 and the vehicle width W2 of the preceding vehicle V2, and the vehicle speed specified by the vehicle speed specifying unit 124. When it is less than the first threshold value Th1 set based on the vehicle speed of V1, the steering control of the vehicle V1 is controlled so as not to be performed. Accordingly, as shown in FIG. 3, it can be confirmed that the displacement amount Dc increases in proportion to the increase in the displacement amount D when the displacement amount D is between 0 and the first threshold value Th1.

When the displacement amount D specified by the displacement amount specifying unit 123 is greater than or equal to the first threshold value Th1, the steering control unit 125 performs steering control of the vehicle V1 so that the vehicle V1 runs following the preceding vehicle V2. Specifically, the steering control unit 125 sets the displacement amount D specified by the displacement amount specifying unit 123 based on a value equal to or greater than the first threshold value Th1 and half the lane width specified by the lane width specifying unit 122. is less than the second threshold Th2, the steering control of the vehicle V1 is performed so that the distance in the vehicle width direction between the vehicle V1 and the preceding vehicle V2 is maintained at the first threshold Th1. Here, the steering control unit 125 sets the second threshold Th2 based on the half value of the lane width and the gain G used for setting the first threshold Th1. Specifically, the steering control unit 125 sets the second threshold value Th2 by multiplying the half value of the lane width and the gain G.

In the example shown in FIG. 3, when the displacement amount D is between the first threshold value Th1 and the second threshold value Th2, the displacement amount Dc is the first threshold value Th1, that is, the vehicle width W1 of the vehicle V1 and the vehicle width W2 of the preceding vehicle V2. , and it can be confirmed that the vehicle V1 and the preceding vehicle V2 follow-up with the right edge aligned with the right edge.

Further, the steering control unit 125 determines that the displacement amount D specified by the displacement amount specifying unit 123 is equal to or greater than the second threshold Th2 and less than the third threshold Th3, which is the sum of the first threshold Th1 and the second threshold Th2. When the displacement amount D increases, steering control of the vehicle V1 is performed so that the distance in the vehicle width direction between the vehicle V1 and the preceding vehicle V2 is shortened.

Specifically, the steering control unit 125 controls the vehicle V1 so that the relationship between the amount of displacement D and the amount of displacement Dc satisfies the following equation (1).
Dc=-Th1/(Th3-Th2) D+Th1*Th3/(Th3-Th2) (1)
Here, since the third threshold Th3 is the sum of the first threshold Th1 and the second threshold Th2, Equation (1) is converted to Equation (2).
Dc=-D+Th1+Th2 (2)

In the example shown in FIG. 3, when the displacement amount D is between the second threshold Th2 and the third threshold Th3, the displacement amount Dc decreases as the displacement amount D increases, and the displacement amount D reaches the third threshold Th3. Then, it can be confirmed that the displacement amount Dc is 0, that is, the positions in the vehicle width direction of the vehicle V1 and the preceding vehicle V2 are aligned.

Further, when the displacement amount D specified by the displacement amount specifying unit 123 is equal to or greater than the third threshold value Th3, the steering control unit 125 causes the predetermined position of the vehicle V1 in the vehicle width direction to match the predetermined position of the preceding vehicle V2. Steering control is performed as follows.

Note that when the displacement amount D specified by the displacement amount specifying unit 123 is equal to or greater than the third threshold value Th3, there is a high possibility that the preceding vehicle V2 changes lanes or travels on a curve. . Therefore, when the displacement amount D specified by the displacement amount specifying unit 123 is equal to or greater than the third threshold value Th3, the steering control unit 125 determines whether or not the preceding vehicle V2 operates the direction indicator, If it is determined that the device is operating, the follow-up running may be stopped.

Further, when the displacement amount D specified by the displacement amount specifying unit 123 is equal to or greater than the third threshold value Th3, the steering control unit 125 determines that the vehicle is traveling on a curve when determining that the direction indicator is not operated. However, the steering control may be performed so that the position of the vehicle V1 in the vehicle width direction coincides with the position of the preceding vehicle V2 in the vehicle width direction, regardless of the amount of displacement D, until a new lane is detected.

[Flow of processing in the steering control device 10]
Next, a flow of processing relating to steering control in the steering control device 10 when the vehicle width of the preceding vehicle V2 is smaller than the vehicle width of the vehicle V1 will be described. FIG. 5 is a flowchart showing the flow of processing relating to steering control when the vehicle width of the preceding vehicle V2 is smaller than that of the vehicle V1. The processing according to this flowchart is executed, for example, every predetermined time (for example, 10 milliseconds).

First, the vehicle width identification unit 121 identifies the vehicle widths of the vehicle V1 and the preceding vehicle V2 (S1).
Subsequently, the lane width identification unit 122 identifies the lane width of the lane on which the vehicle V1 travels (S2).

Subsequently, the displacement amount specifying unit 123 sets the displacement amount D from the center position of the lane in which the vehicle V1 travels to the position of the preceding vehicle V2 (S3).
Subsequently, the steering control unit 125 specifies the first threshold value Th1 to the third threshold value Th3 (S4).

Subsequently, the steering control unit 125 determines whether or not the displacement amount D is less than the first threshold Th1 (S5). When the steering control unit 125 determines that the displacement amount D is less than the first threshold value Th1, the steering control unit 125 does not perform steering control so that the vehicle V1 follows the preceding vehicle V2, and ends the processing according to this flowchart. When the steering control unit 125 determines that the displacement amount D is equal to or greater than the first threshold value Th1, the process proceeds to S6.

In S6, the steering control unit 125 determines whether or not the displacement amount D is less than the second threshold Th2. If the steering control unit 125 determines that the displacement amount D is less than the second threshold Th2, the process proceeds to S7, and if it determines that the displacement amount D is equal to or greater than the second threshold Th2, the process proceeds to S8.

In S7, the steering control unit 125 performs steering control so that the distance (displacement amount Dc) between the vehicle V1 and the preceding vehicle V2 is maintained at the first threshold value Th1.

In S8, the steering control unit 125 determines whether or not the displacement amount D is less than the third threshold Th3. If the steering control unit 125 determines that the displacement amount D is less than the third threshold Th3, the process proceeds to S9, and if it determines that the displacement amount D is equal to or greater than the third threshold Th3, the process proceeds to S10.

In S9, the steering control unit 125 performs steering control so that the distance between the vehicle V1 and the preceding vehicle V2 maintains the above-mentioned formula (2).
In S10, the steering control unit 125 performs steering control so that the vehicle V1 and the preceding vehicle V2 are aligned in the vehicle width direction.

[Effects of this embodiment]
As described above, the steering control device 10 according to the present embodiment specifies the vehicle width of the vehicle V1 and the vehicle width of the preceding vehicle V2 traveling in front of the vehicle V1, and determines the width of the vehicle V1 in the center of the lane in which the vehicle V1 travels. A displacement amount, which is the distance from the position to the position of the preceding vehicle V2, is specified. Then, when the vehicle width of the preceding vehicle V2 is smaller than the vehicle width of the vehicle V1, the steering control device 10 determines that the specified displacement amount is half the difference between the vehicle width of the vehicle V1 and the vehicle width of the preceding vehicle V2. is less than the first threshold value Th1 set based on the value of, the steering control of the vehicle V1 is not performed so that the vehicle V1 runs following the preceding vehicle V2, and the specified displacement amount is greater than or equal to the first threshold value Th1. , the steering control of the vehicle V1 is performed so that the vehicle V1 runs following the preceding vehicle V2. By doing so, the behavior of the vehicle V1 can be stably run.

Further, the steering control unit 125 of the steering control device 10 sets the first threshold Th1 such that the higher the vehicle speed of the vehicle V1, the smaller the first threshold Th1. When the first threshold Th1 is small, the steering control device 10 can follow the preceding vehicle V2 earlier than when the first threshold Th1 is large. Thus, when the preceding vehicle V2 enters a curve or the like, the vehicle V1 can quickly follow the preceding vehicle V2 and the yaw rate can be reduced, so that the behavior of the vehicle V1 can be stabilized.

Further, the steering control unit 125 of the steering control device 10 sets the first threshold Th1 so that when the inter-vehicle distance between the vehicle V1 and the preceding vehicle V2 is small, the first threshold Th1 is larger than when the inter-vehicle distance is large. Set Th1. When following the preceding vehicle V2 early when the inter-vehicle distance is small, the steering amount of the vehicle V1 becomes large and the behavior of the vehicle V1 becomes unstable. In contrast, when the inter-vehicle distance between the vehicle V1 and the preceding vehicle V2 is small, the steering control device 10 sets the first threshold Th1 so that the first threshold Th1 becomes large. Instability can be suppressed.

Although the present invention has been described above using the embodiments, the technical scope of the present invention is not limited to the scope described in the above embodiments, and various modifications and changes are possible within the scope of the gist thereof. be. For example, all or part of the device can be functionally or physically distributed and integrated in arbitrary units. In addition, new embodiments resulting from arbitrary combinations of multiple embodiments are also included in the embodiments of the present invention. The effect of the new embodiment caused by the combination has the effect of the original embodiment.

Reference Signs List 1 imaging device 2 vehicle speed sensor 3 motor 10 steering control device 11 storage unit 12 control unit 121 vehicle width specifying unit 122 lane width Identification unit 123 Displacement amount identification unit 124 Vehicle speed identification unit 125 Steering control unit V Vehicle

Claims (7)

A steering control device that performs steering control of a vehicle,
a vehicle width identification unit that identifies the vehicle width of the vehicle and the vehicle width of a preceding vehicle traveling in front of the vehicle;
a displacement amount specifying unit that specifies a displacement amount that is a distance from the center position of the lane in which the vehicle travels to a predetermined position of the preceding vehicle;
When the vehicle width of the preceding vehicle is smaller than the vehicle width of the vehicle, the displacement amount specified by the displacement amount specifying unit is half the difference between the vehicle width of the vehicle and the vehicle width of the preceding vehicle. is less than the first threshold set based on the value, the steering control of the vehicle is not performed so that the vehicle runs following the preceding vehicle, and the displacement amount specified by the displacement amount specifying unit is a steering control unit that performs steering control of the vehicle so that the vehicle runs following the preceding vehicle when the first threshold is equal to or greater than the first threshold;
A steering control device comprising: further comprising a lane width identifying unit that identifies the lane width of the lane on which the vehicle travels,
When the vehicle width of the preceding vehicle is smaller than the vehicle width of the vehicle, the steering control unit determines that the displacement amount specified by the displacement amount specifying unit is equal to or greater than the first threshold value, and the lane width specifying unit is less than a second threshold value set based on the specified half value of the lane width, the distance of the vehicle in the vehicle width direction between the vehicle and the preceding vehicle maintains the first threshold value. perform steering control,
A steering control device according to claim 1 . When the vehicle width of the preceding vehicle is smaller than the vehicle width of the vehicle, the steering control unit determines that the displacement amount identified by the displacement amount identification unit is the sum of the first threshold value and the second threshold value. and performing the steering control so that the predetermined position of the vehicle in the vehicle width direction coincides with the predetermined position of the preceding vehicle,
A steering control device according to claim 2 . When the vehicle width of the preceding vehicle is smaller than the vehicle width of the vehicle, the steering control unit determines that the displacement amount specified by the displacement amount specifying unit is equal to or greater than the second threshold value and the third threshold value. When the distance is less than the displacement amount, the steering control of the vehicle is performed so that the distance in the vehicle width direction between the vehicle and the preceding vehicle is shortened according to the increase in the displacement amount.
A steering control device according to claim 3 . further comprising a vehicle speed identification unit that identifies the vehicle speed of the vehicle;
The steering control unit sets the threshold further based on the vehicle speed of the vehicle identified by the vehicle speed identification unit.
A steering control device according to any one of claims 1 to 4. further comprising an inter-vehicle distance specifying unit that specifies an inter-vehicle distance between the vehicle and the preceding vehicle,
The steering control unit sets the threshold further based on the inter-vehicle distance specified by the inter-vehicle distance specifying unit.
A steering control device according to any one of claims 1 to 5. A steering control method for performing steering control of a vehicle,
Executed by a computer that performs steering control of the vehicle,
identifying a vehicle width of the vehicle and a vehicle width of a preceding vehicle traveling in front of the vehicle;
a step of identifying a displacement amount, which is a distance from a center position in the lane width direction of the lane in which the vehicle travels to a predetermined position of the preceding vehicle;
When the vehicle width of the preceding vehicle is smaller than the vehicle width of the vehicle, the displacement amount is set based on a half value of the difference between the vehicle width of the vehicle and the vehicle width of the preceding vehicle. When the displacement amount is less than one threshold value, the steering control of the vehicle is not performed so that the vehicle runs following the preceding vehicle, and when the displacement amount is equal to or greater than the first threshold value, the vehicle follows the preceding vehicle. a step of performing steering control of the vehicle so as to follow and run;
A steering control method comprising :

Images