JP7204437B2 - VEHICLE DRIVING CONTROL METHOD AND VEHICLE DRIVING CONTROL SYSTEM - Google Patents

Description

The present invention relates to a vehicle cruise control method and a vehicle cruise control system.

Patent Literature 1 proposes a vehicle travel control device that causes a host vehicle traveling in a travel lane to change lanes to an adjacent lane that is congested. This vehicle travel control device determines whether or not a space (inter-vehicle distance) for the vehicle to enter exists in the adjacent lane, and moves the vehicle to the space when it is determined that the space exists.

On the other hand, when it is determined that there is no space, the vehicle travel control device moves the host vehicle to a standby position (a position closer to the adjacent lane) to wait. Then, at the standby position, the own vehicle is given a speed change to interrupt or delay the lane change, and the vehicle in the adjacent lane is encouraged to leave a space necessary for the lane change.

JP 2016-203745 A

However, in the vehicle running control device of Patent Document 1, the own vehicle waits at the standby position until it is determined whether or not the vehicle in the adjacent lane will provide a space for the lane change. Regarding this point, in Patent Document 1, when a predetermined waiting time elapses without the vehicle in the adjacent lane leaving a space, or when more than a predetermined number of vehicles in the adjacent lane pass the own vehicle, the lane A control that performs a process of canceling the change has been proposed.

However, with such control, it takes a relatively long time to determine that the lane change should be stopped.

In view of such circumstances, it is an object of the present invention to provide a vehicle cruise control method and a vehicle cruise control system that are capable of realizing a prompt decision to stop lane change control.

According to one aspect of the present invention, there is provided a vehicle travel control method in which a controller executes lane change control for causing a host vehicle traveling in a travel lane to enter between vehicles traveling in an adjacent lane. In this vehicle travel control method, when the lane change control is started, the controller identifies a rear vehicle positioned behind the own vehicle in the adjacent lane, and when the rear vehicle is identified, moves the own vehicle from the travel position in the travel lane to the adjacent lane. Move to a closer parallel running position. Further, the controller obtains a rear vehicle acceleration that is the acceleration of the rear vehicle after the host vehicle has moved to the parallel running position, and if the rear vehicle acceleration is equal to or greater than a predetermined first rear vehicle acceleration threshold, lane change control is performed. cancel .

ADVANTAGE OF THE INVENTION According to this invention, the prompt cancellation judgment in lane change control is implement|achieved.

FIG. 1 is a diagram illustrating the configuration of a vehicle travel control system common to each embodiment of the present invention. FIG. 2 is a flowchart showing lane change control. FIG. 3 is a diagram schematically showing an example of the travel locus of the own vehicle under the parallel running process. FIG. 4 is a flowchart showing parallel running processing. FIG. 5 is a flow chart showing the main determination mode of the first embodiment. FIG. 6 is a flow chart showing the main determination mode of the second embodiment. FIG. 7 is a flow chart showing the main determination mode of the third embodiment. FIG. 8 is a flow chart showing the main determination mode of the fourth embodiment. FIG. 9 is a flowchart showing lane change control according to the fifth embodiment. FIG. 10 is a flow chart showing the sub-determination mode. FIG. 11 is a diagram schematically showing an example of the travel locus of the own vehicle under the next parallel position movement processing. FIG. 12 is a flow chart showing the stop position determination mode. FIG. 13 is a diagram illustrating an example of a specific scene in which the stop position determination mode is executed.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(First embodiment)
A first embodiment will be described with reference to FIGS. 1 to 5. FIG. FIG. 1 is a configuration diagram of a vehicle travel control system 10 according to this embodiment.

As shown, the vehicle cruise control system 10 includes an external sensor 1, an internal sensor 2, a navigation system 3, an actuator 4, and a controller 20. The vehicle cruise control system 10 is installed in a vehicle (hereinafter referred to as "self-vehicle α") on which the vehicle cruise control method of the present embodiment is to be executed.

The external sensor 1 is a detection device that detects an external situation Iec, which is peripheral information of the own vehicle α. In particular, the external sensors 1 include an onboard camera 1a and a radar 1b.

The in-vehicle camera 1a is imaging equipment that captures an image of the external situation Iec of the own vehicle α. The in-vehicle camera 1a is provided, for example, on the interior side of the windshield of the own vehicle α. In addition, the vehicle-mounted camera 1a is configured by a monocular camera or a stereo camera. The in-vehicle camera 1a outputs imaging information regarding the external situation Iec of the own vehicle α to the controller 20 as the external situation Iec.

The radar 1b uses radio waves to detect objects outside the own vehicle α. Radio waves are, for example, millimeter waves. More specifically, the radar 1b detects objects by transmitting radio waves around the vehicle α and receiving radio waves reflected by objects. The radar 1b can output, for example, the distance or direction to an object as object information. The radar 1b outputs the detected object information to the controller 20 as the external situation Iec. Instead of or in addition to the radar 1b, a LIDER (Laser Imaging Detection and Ranging) that uses light to detect an object outside the vehicle α may be mounted as the external sensor 1.

The internal sensor 2 is a detector that detects various information according to the running state of the own vehicle α. In particular, the internal sensors 2 include a vehicle speed sensor 2a and an acceleration sensor 2b.

The vehicle speed sensor 2a is a sensor that detects the vehicle speed of the own vehicle α (hereinafter also referred to as "own vehicle speed Vα"). The vehicle speed sensor 2a is composed of, for example, a pulse generator such as a rotary encoder for measuring wheel speed. The vehicle speed sensor 2a outputs the detected wheel speed information (vehicle speed Vα) to the controller 20 .

The acceleration sensor 2b is a detector that detects the acceleration of the own vehicle α (hereinafter also referred to as “own vehicle acceleration Aα”). The acceleration sensor 2 b outputs the own vehicle acceleration Aα to the controller 20 .

The navigation system 3 is a device that guides an occupant of the own vehicle α to a destination set on a map by an occupant such as a driver of the own vehicle α. The navigation system 3 calculates a route for the vehicle α based on position information of the vehicle α measured by a GPS (Global Positioning System) and map information in a map database (not shown). The route may be, for example, a route in which the driving lane La1 on which the vehicle α travels is specified in a section of multiple lanes. The navigation system 3, for example, calculates a target route from the position of the own vehicle α to the destination, and notifies the passengers of the target route information through display on the display and voice output from the speaker. The navigation system 3 outputs to the controller 20 navigation information Ina including the position information of the own vehicle α, map information, and target route information.

The navigation system 3 may use information stored in a computer in a facility outside the vehicle such as an information processing center that can communicate with the vehicle α. For example, the navigation system 3 may acquire, as the navigation information Ina, congestion information indicating road congestion from a computer in the facility via communication. Further, the processing executed by the navigation system 3 may be distributed between a computer mounted on the own vehicle α and a computer outside the vehicle.

The actuator 4 is a device that executes travel control of the own vehicle α based on a command from the controller 20 . Actuators 4 include drive actuators 4a, brake actuators 4b, and steering actuators 4c.

The driving actuator 4a is a device for adjusting the driving force of the own vehicle α.

In particular, when the own vehicle α is an internal combustion engine vehicle equipped with an engine as a drive source, the drive actuator 4a is composed of a throttle actuator or the like for adjusting the amount of air supplied to the engine (throttle opening). be.

On the other hand, when the own vehicle α is a hybrid vehicle or an electric vehicle equipped with a motor as a drive source, the drive actuator 4a is a circuit (inverter, converter, etc.) capable of adjusting the electric power supplied to the motor. Configured.

The brake actuator 4b is a device that operates the brake system according to a command from the controller 20 and adjusts the braking force applied to the wheels of the own vehicle α. The brake actuator 4b is composed of a hydraulic brake, a regenerative brake, or the like.

The steering actuator 4c is composed of an assist motor or the like for controlling the steering torque of the electric power steering system.

The controller 20 is composed of a computer having a central processing unit (CPU), a read only memory (ROM), a random access memory (RAM) and an input/output interface (I/O interface). Note that the controller 20 may be composed of one computer, or may be composed of a plurality of computers.

The controller 20 of this embodiment is configured by a device such as an ECU (Engine Control Unit) mounted on the own vehicle α, for example. Further, when the own vehicle α is a vehicle equipped with a so-called automatic driving function, the function of the controller 20 of the present embodiment may be incorporated into an automatic driving controller that executes a process for realizing the automatic driving function. good.

The controller 20 is configured to be able to communicate various signals with the external sensor 1 , the internal sensor 2 and the navigation system 3 . In particular, the controller 20 receives (obtains) the external situation Iec from the external sensor 1 . Further, the controller 20 receives (obtains) the detected value of the vehicle speed Vα and the detected value of the vehicle acceleration Aα from the internal sensor 2 . Further, the controller 20 receives (acquires) navigation information Ina from the navigation system 3 .

The controller 20 is programmed to appropriately operate the actuator 4 based on the acquired detection values and information to execute the vehicle travel control method of the present embodiment (particularly lane change control, which will be described later). .

In particular, the controller 20 of the present embodiment is triggered by detection of a lane change request including a predetermined lane change command and completion of reroute processing, which will be described later, in a state in which the own vehicle α is traveling in the travel lane La1. Start controlling. Here, the command to change lanes includes an operation (for example, an operation on a direction indicator) by a passenger or the like to command the start of a lane change (for example, an operation on a direction indicator) or a command from a higher-level automatic driving controller.

The lane change control can be executed in any scene when the own vehicle α is traveling at low speed or at high speed. is particularly preferred. The lane change control will be described in detail below.

FIG. 2 is a flowchart showing lane change control according to this embodiment.

In step S<b>110 , the controller 20 acquires the above detection values and information from the external sensor 1 , internal sensor 2 and navigation system 3 .

In step S120, the controller 20 executes parallel running processing for moving the own vehicle α to the parallel running position P1.

FIG. 3 is a diagram schematically showing an example of the travel trajectory of the host vehicle α under the parallel running process.

As shown in the figure, the parallel running process of the present embodiment involves moving the host vehicle α from its original running position (hereinafter also referred to as "normal running position P0") on the running lane La1 to a parallel running position P1 closer to the adjacent lane La2. (See the dashed line). Here, the parallel running position P1 is defined as a position on the traveling lane La1 laterally aligned (opposing) to the distance X between the forward vehicle β and the rearward vehicle γ in the adjacent lane La2. Each step in the parallel running process will be described below.

FIG. 4 is a flowchart showing parallel running processing.

First, in step S121, the controller 20 identifies the rear vehicle γ and the front vehicle β to be changed lanes. Specifically, the controller 20 identifies a target vehicle (hereinafter also referred to as a "rear vehicle γ") that is behind the host vehicle α on the adjacent lane La2 and has the shortest distance in the longitudinal direction. do. Furthermore, the controller 20 identifies a vehicle adjacent to the rear vehicle γ in the front direction (the vehicle one ahead) on the adjacent lane La2 as the front vehicle β.

In step S122, the controller 20 calculates a target value of the distance from the front end of the rear vehicle γ in the vehicle length direction to the approximate center position of the own vehicle α (hereinafter also referred to as "front-rear target position Lαγ").

Specifically, the controller 20 calculates a suitable front-rear target position Lαγ from the viewpoint of moving the host vehicle α from the normal running position P0 to the parallel running position P1. More specifically, the controller 20 calculates the longitudinal target position Lαγ based on the following equation (1).

Note that "Lαγ_m" in the formula (1) means a predetermined lower limit value set for the front-rear target position Lαγ. Further, "Dv/2" is a value of 1/2 of the inter-vehicle distance Dv (the length of the inter-vehicle distance X in the traveling direction) between the forward vehicle β and the rearward vehicle γ, and is the basic control set to the front-rear target position Lαγ. value. That is, the longitudinal target position Lαγ is set to the larger value of 1/2 of the inter-vehicle distance Dv and the lower limit value Lαγ_m.

As the inter-vehicle distance Dv is small, the target longitudinal position Lαγ set according to the formula (1) is set smaller accordingly, and the distance between the own vehicle α and the vehicle behind γ becomes shorter. Therefore, it is assumed that the display of the direction indicator for lane change by the own vehicle α cannot be recognized visually by the occupants of the rear vehicle γ and by the camera mounted in front of the rear vehicle γ.

In order to suppress the occurrence of such a situation, a lower limit value Lαγ_m is set for the longitudinal target position Lαγ.

Next, in step S123, the controller 20 calculates a target value of the lateral distance from the approximate center position of the vehicle α to the adjacent lane La2 (hereinafter also referred to as "target lateral distance Dαγ").

Specifically, the controller 20 calculates the target lateral distance Dαγ based on the following equation (2).

Note that "Dαγ_ba" in the formula is a basic control value for the target lateral distance Dαγ that is determined as appropriate. Also, "Dαγ_c" is the lower limit value of the target lateral distance Dαγ that is set in consideration of a margin necessary for safety from the viewpoint of avoiding contact between the vehicle α and the vehicle ahead β or the vehicle behind γ. That is, the target lateral distance Dαγ is set to the larger one of the basic control value Dαγ_ba and the lower limit value Dαγ_c.

Note that the lower limit value Dαγ_c can be appropriately determined from the viewpoint of ensuring a margin necessary for safety based on the accuracy of detecting the positions of the forward vehicle β and the rear vehicle γ, and the driving conditions such as the vehicle speed and angular velocity of each vehicle. .

Then, in step S124, the controller 20 operates the actuator 4 based on the set target front-rear position Lαγ and target lateral distance Dαγ to move the host vehicle α to and maintain the parallel running position P1.

After executing the process of step S124, the next controller 20 proceeds to the process of step S130 in FIG.

In step S130, the controller 20 executes the main determination mode.

FIG. 5 is a flow chart showing the main determination mode.

First, in step S131, the controller 20 calculates the inter-vehicle distance Dv, the acceleration of the rear vehicle γ (hereinafter also referred to as "rear vehicle acceleration Aγ"), and the inter-vehicle distance increase amount ΔDv.

Specifically, the controller 20 calculates the inter-vehicle distance Dv from the positional information of the forward vehicle β and the positional information of the rearward vehicle γ included in the external situation Iec from the external sensor 1 (especially the object information from the radar 1b).

Further, the controller 20 calculates a rear vehicle acceleration Aγ based on the following equation (3) from the longitudinal target position Lαγ and the host vehicle acceleration Aα.

The first term on the right side of equation (3) means the second-order differential of the longitudinal target position Lαγ with respect to time. While computing the rearward vehicle acceleration Aγ based on the above equation (3), it is also possible to appropriately perform corrections for suppressing errors that occur according to the detection accuracy of each sensor and the size of the sampling period.

Further, the controller 20 subtracts the previous value from the current value of the inter-vehicle distance Dv to calculate an inter-vehicle distance increase amount ΔDv. Therefore, when the inter-vehicle distance Dv tends to increase, the inter-vehicle distance increase amount ΔDv takes a positive value, and when it tends to decrease, it takes a negative value.

Next, the controller 20 makes determinations in steps S132 to S134. If the results of these determinations are all affirmative, the controller 20 immediately ends the main determination mode and proceeds to the process of step S150. On the other hand, if any one of these determinations is negative, the controller 20 proceeds to step S135. Details of each determination will be described below.

First, in step S132, the controller 20 determines whether or not the calculated inter-vehicle distance Dv is greater than a predetermined inter-vehicle distance threshold Dv_Th1. Here, the inter-vehicle distance threshold Dv_Th1 is determined from the viewpoint of whether or not the inter-vehicle distance X is sufficiently wide enough for the own vehicle α to enter. In particular, the inter-vehicle distance threshold Dv_Th1 is appropriately determined in consideration of the overall length of the own vehicle α and a margin set from the viewpoint of safety.

Then, when the controller 20 determines that the inter-vehicle distance Dv is greater than the inter-vehicle distance threshold value Dv_Th1, the process proceeds to step S133.

In step S133, the controller 20 determines whether or not the inter-vehicle distance increase amount ΔDv is greater than a predetermined inter-vehicle distance increase amount threshold value ΔDv_Th1. Here, the inter-vehicle distance increase threshold value ΔDv_Th1 is determined from the viewpoint of whether or not the inter-vehicle distance Dv tends to increase to the extent that the own vehicle α does not impede entry into the inter-vehicle distance X.

That is, even if the inter-vehicle distance Dv is sufficiently large, the inter-vehicle distance increase threshold ΔDv_Th1 is set when the inter-vehicle distance X tends to narrow, such as when the relative vehicle speed of the rear vehicle γ with respect to the front vehicle β is high. It is set with the intention of aborting the change. The vehicle distance increase threshold ΔDv_Th1 can be set to 0 or a negative value, for example.

In step S134, the controller 20 determines whether or not the rear vehicle acceleration Aγ is greater than or equal to the first rear vehicle acceleration threshold Aγ_Th1. Here, the first rear vehicle acceleration threshold value Aγ_Th1 is set so that the driver of the rear vehicle γ enters the inter-vehicle distance X after the driver of the rear vehicle γ grasps the indication of the intention of the vehicle α to change lanes, such as the display of the direction indicator. is set from the viewpoint of whether or not the rear vehicle acceleration Aγ is low enough to determine that the

For example, the first rear vehicle acceleration threshold Aγ_Th1 can be set to zero. As a result, when the rear vehicle acceleration Aγ is determined to be 0 or more (when the rear vehicle γ is accelerated), it is regarded as a state in which the own vehicle α is not allowed to enter the distance X (a state in which there is no intention to yield). be able to. Conversely, when the rear vehicle acceleration Aγ is less than 0 (when the speed of the rear vehicle γ is maintained or decelerated), the state in which the own vehicle α is permitted to enter the distance X (the state in which there is an intention to yield ).

As a result, in this embodiment, by referring to the rear vehicle acceleration Aγ, it is possible to quickly determine whether or not the driver of the rear vehicle γ intends to allow the own vehicle α to enter the distance X. .

When the controller 20 determines that the rear vehicle acceleration Aγ is smaller than the first rear vehicle acceleration threshold Aγ_Th1 (No in step S134), the process proceeds to step S140 in FIG. On the other hand, when the controller 20 determines that the rear vehicle acceleration Aγ is greater than or equal to the first rear vehicle acceleration threshold Aγ_Th1 (Yes in step S134), the process proceeds to step S135.

In step S135, the controller 20 sets the stop flag indicating that the lane change control should be stopped to "1". After completing the process of step S135, the controller 20 proceeds to the process of step S140.

Returning to FIG. 2, in step S140, the controller 20 determines whether the stop flag is "0". When the controller 20 determines that the stop flag is "0", the process proceeds to step S150.

In step S150, the controller 20 performs a lane change operation. Specifically, the controller 20 causes the own vehicle α to enter the space X between the front vehicle β and the rear vehicle γ based on the respective position information and vehicle speed information of the own vehicle α, the front vehicle β, and the rear vehicle γ. Calculate the running trajectory of Then, the controller 20 drives and steers the own vehicle α by operating the actuator 4 based on the calculated travel locus.

Regarding the specific control for the controller 20 to allow the own vehicle α to enter the distance X between the vehicles, the values of the target front-rear position Lαγ and the target lateral distance Dαγ in the parallel running process are appropriately changed and the same logic is applied. It is possible to run

On the other hand, when the controller 20 determines that the stop flag is not "0" in step S140 (that is, determines that the stop flag is set to "1"), the process proceeds to step S160.

In step S160, the controller 20 cancels the lane change. Specifically, the controller 20 performs return processing for returning the own vehicle α to the normal running position P0 (see FIG. 3). Further, the controller 20 executes a reroute process after or in parallel with the completion of the return process. Here, the reroute process is a process of searching for an opportunity to enable lane change control next time.

In the reroute process, the controller 20 refers to the navigation information Ina and the like to specify two vehicles other than the combination of the forward vehicle β and the backward vehicle γ traveling in the adjacent lane La2 as target vehicles. That is, for example, the controller 20 identifies the forward vehicle β and the vehicle further ahead, the rear vehicle γ and the vehicle further behind, or other two vehicles as target vehicles for the lane change. Then, the controller 20 regards the specified two vehicles as the new front vehicle β and rear vehicle γ, and similarly executes each process described with reference to FIG. 2 .

According to this embodiment having the configuration described above, the following effects are obtained.

In the present embodiment, the vehicle travel control method is such that the controller 20 executes lane change control to allow the host vehicle α traveling in the travel lane La1 to enter between the vehicles (the forward vehicle β and the rearward vehicle γ) traveling in the adjacent lane La2. provided.

In this vehicle travel control method, when the controller 20 starts the lane change control, the controller 20 causes the own vehicle α to travel side by side between the vehicles X on the adjacent lane La2 at the parallel running position P1 on the driving lane La1 (step S120 in FIG. 2 and FIG. 4). ). Then, when the controller 20 determines that the rear vehicle acceleration Aγ, which is the acceleration of the rear vehicle γ among the vehicles, is equal to or greater than a predetermined first rear vehicle acceleration threshold Aγ_Th1 (see FIG. 5). If yes in step S134), the lane change control is stopped (step S135 in FIG. 5, No in step S140 in FIG. 2, and step S160).

Accordingly, the controller 20 refers to the rear vehicle acceleration Aγ to determine whether or not the rear vehicle γ is willing to allow the rear vehicle γ to change lanes, that is, to allow the rear vehicle γ to enter the distance X by the vehicle α. can be suitably determined, and the lane change control for the own vehicle α can be promptly stopped according to the determination (step S160 in FIG. 2). That is, based on the rear vehicle acceleration Aγ, it is possible to quickly detect the intention of the driver of the rear vehicle γ to reject the lane change operation of the own vehicle α, and stop the lane change control.

Therefore, it is possible to suppress the occurrence of a delay in the decision to stop the lane change control due to the host vehicle α continuing to wait at the parallel running position P1 in a state where there is no space necessary for lane change. In particular, by realizing such a prompt decision to stop lane change control, it is possible to suitably ensure an opportunity to search for the next appropriate timing for lane change control. As a result, the lane change cannot be completed until the desired point (the place where the lane change operation is required to be completed according to the request such as left turn, right turn, or straight ahead for the own vehicle α). The occurrence can also be suppressed.

Note that in this embodiment, the first rear vehicle acceleration threshold Aγ_Th1, which is the reference for the rear vehicle acceleration Aγ for determining whether or not to stop the lane change control, is set to zero. As a result, the lane change control is stopped when the acceleration of the rear vehicle γ is detected regardless of its magnitude.

As a result, a decrease in the inter-vehicle distance X (inter-vehicle distance Dv) at the destination of the own vehicle α resulting from the acceleration of the rear vehicle γ or a decrease in the inter-vehicle distance increase amount ΔDv indicating the change in the inter-vehicle distance Dv is monitored. The cancellation judgment can be executed more quickly than the cancellation judgment of the lane change control to be executed. Note that the first rear vehicle acceleration threshold value Aγ_Th1 is a value other than 0 (a value exceeding 0 or a value exceeding 0) as long as it functions as a criterion for determining whether or not the rear vehicle γ permits the lane change operation of the own vehicle α. value below).

Furthermore, in the vehicle travel control method of the present embodiment, the controller 20 searches for an opportunity when the lane change control can be executed again (reroute processing) after stopping the lane change control.

As a result, the reroute process is executed subsequent to the above-described prompt suspension of the lane change control, so it is possible to further increase the possibility of discovering a situation in which the lane change control becomes possible next time. As a result, it is possible to preferably suppress the occurrence of a situation in which the lane change operation is not completed by the desired point (such as an intersection) where the lane change operation of the own vehicle α is required to be completed.

Further, according to this embodiment, a vehicle cruise control system 10 for executing the vehicle cruise control method is provided.

In the vehicle travel control system 10, the controller executes lane change control for causing the own vehicle α traveling in the travel lane La1 to enter between the vehicles (the forward vehicle β and the rearward vehicle γ) traveling in the adjacent lane La2.

The vehicle running control system 10 includes an external sensor 1 that detects the respective positions of the vehicle, an internal sensor 2 that detects the vehicle speed (own vehicle speed Vα) and acceleration (own vehicle acceleration Aα) of the own vehicle α, and the own vehicle and a controller 20 that operates the actuator 4 based on the values detected by the internal sensor 2 and the external sensor 1 .

When the controller 20 receives the lane change request, the controller 20 starts lane change control (FIG. 2), and when the lane change control is started, the host vehicle α runs side by side with the vehicle X in the adjacent lane La2 in the traveling lane La1 (FIG. 2). 2 and step 120 in FIG. 3). Further, the controller 20 acquires the position information of the forward vehicle β and the backward vehicle γ, the vehicle speed Vα and the vehicle acceleration Aα from the external sensor 1 and the internal sensor 2, respectively, while the vehicle α is running side by side. Furthermore, the controller 20 calculates the rear vehicle acceleration Aγ, which is the acceleration of the rear vehicle γ, based on the position information of the front vehicle β and the rear vehicle γ, the own vehicle speed Vα, and the own vehicle acceleration Aα (step S131 in FIG. 5). ). Then, the controller 20 determines whether or not the rear vehicle acceleration Aγ is greater than or equal to a predetermined first rear vehicle acceleration threshold Aγ_Th1 (step S134), and if the result of the determination is affirmative, lane change control is performed. Stop (step S135 in FIG. 5, No in step S140 in FIG. 2, and step S160).

Thereby, a suitable system configuration for executing the above-described vehicle travel control method is realized.

(Second embodiment)
A second embodiment will be described below with reference to FIG. Elements similar to those of the first embodiment are assigned the same reference numerals, and descriptions thereof are omitted. In the present embodiment, in particular, in calculating the first rear vehicle acceleration threshold Aγ_Th1 used in the determination of step S134 (FIG. 5) in the first embodiment, the acceleration of the forward vehicle β (hereinafter also referred to as "forward vehicle acceleration Aβ") is considered, which is different from the first embodiment.

FIG. 6 is a flowchart showing the main determination mode in the vehicle travel control method of this embodiment.

In this embodiment, the controller 20 proceeds to the process of step S131' after calculating the inter-vehicle distance Dv, the rear vehicle acceleration Aγ, and the inter-vehicle distance increase amount ΔDv in step S131 described in the first embodiment.

In step S131', the controller 20 calculates the forward vehicle acceleration Aβ based on the following equation (4) from the target longitudinal position Lαγ (see equation (1) above), the inter-vehicle distance Dv, and the host vehicle acceleration Aα.

In step S131'', the controller 20 calculates a corrected first rear vehicle acceleration threshold Aγ_Th1 (Aβ) based on the front vehicle acceleration Aβ. Specifically, the controller 20 determines the first rear vehicle acceleration threshold Aγ_Th1 as a base in the same manner as in the first embodiment, and corrects the first rear vehicle acceleration threshold Aγ_Th1 such that the larger the front vehicle acceleration Aβ, the larger the first rear vehicle acceleration threshold Aγ_Th1. The calculated value is calculated as the corrected first rear vehicle acceleration threshold value Aγ_Th1 (Aβ).

The technical significance of setting the corrected first rear vehicle acceleration threshold Aγ_Th1 (Aβ) is to determine whether or not the rear vehicle γ permits the lane change operation of the own vehicle α even in the two scenes described below. The purpose of the present invention is to suitably exhibit the accuracy of determination.

First, when the front vehicle acceleration Aβ is a positive value, even if it is determined in step S134 in FIG. A scene is assumed in which the intention is not necessarily to reject the lane change operation of the own vehicle α.

More specifically, when the forward vehicle β is accelerating, the rearward vehicle γ may be accelerated from the viewpoint of not extending the distance X excessively. In this case, it is assumed that the rear vehicle acceleration Aγ is determined to be equal to or greater than the first rear vehicle acceleration threshold Aγ_Th1 even though the rear vehicle γ actually intends to allow the lane change operation of the own vehicle α. be.

In particular, when the driver of the rear vehicle γ recognizes the intention of the lane change operation of the own vehicle α (display of the turn indicator, etc.), the distance X is requested in the distance change operation due to the acceleration of the front vehicle β. It is conceivable to judge that it spreads beyond what is done. In such a case, the rear vehicle γ accelerates to a certain extent from the viewpoint of preventing the distance X from becoming too large, but the following distance Dv necessary for the lane change operation of the own vehicle α is secured. It is envisaged to adjust the rear vehicle acceleration Aγ.

Second, when the front vehicle acceleration Aβ is a negative value, even if it is determined in step S134 in FIG. 5 that the rear vehicle acceleration Aγ is smaller than the first rear vehicle acceleration threshold Aγ_Th1, is not necessarily the intention of permitting the lane change operation of the own vehicle α.

More specifically, when the forward vehicle β is decelerating because the distance between the forward vehicle β and the vehicle further ahead is narrow, the rear vehicle γ recognizes this and prevents the distance X from becoming too narrow. First, it is conceivable to drive in such a way that the rear vehicle acceleration Aγ is maintained or reduced.

In this case, although the rear vehicle γ actually has the intention of refusing the lane change operation of the own vehicle α, detection of a decrease in the rear vehicle acceleration Aγ (that is, the rear vehicle acceleration Aγ vehicle acceleration threshold value Aγ_Th1).

In the vehicle running control method of the present embodiment, even in such a scene, the first rear vehicle acceleration A corrected first rear vehicle acceleration threshold Aγ_Th1 (Aβ) is calculated by correcting the threshold Aγ_Th1 according to the front vehicle acceleration Aβ.

Then, similarly to the first embodiment, the controller 20 proceeds to the determination of step S134' through the affirmative results of the determinations of steps S132 and S133.

In step S134′, the controller 20 changes the magnitude of the corrected first rear vehicle acceleration threshold Aγ_Th1 (Aβ) calculated in step S131″ to the rear vehicle acceleration Aγ instead of the first rear vehicle acceleration threshold Aγ_Th1 of the first embodiment. Determine relationships.

If the rear vehicle acceleration Aγ is greater than or equal to the corrected first rear vehicle acceleration threshold Aγ_Th1 (Aβ), the controller 20 goes through step S135. to run.

According to the vehicle travel control method of the present embodiment having the configuration described above, the following effects are obtained.

In the vehicle running control method of the present embodiment, the controller 20 corrects the first rear vehicle acceleration threshold value Aγ_Th1 so that the larger the forward vehicle acceleration Aβ as the acceleration of the forward vehicle β among the vehicles (FIG. 6). step S131'').

That is, the front vehicle acceleration Aβ is included in the factors that determine the first rear vehicle acceleration threshold Aγ_Th1 used to determine whether or not the rear vehicle γ permits the vehicle α to enter the lane for lane change. In particular, the first rear vehicle acceleration threshold value Aγ_Th1 can be set in consideration of the increase and decrease (including maintenance) of the rear vehicle acceleration Aγ caused by the acceleration and deceleration of the forward vehicle β described above.

Therefore, it is possible to realize a more accurate determination that takes into consideration changes in the rear vehicle acceleration Aγ that may occur regardless of whether the rear vehicle γ intends to allow the lane change operation of the own vehicle α. As a result, it is possible to more accurately determine whether or not the following vehicle γ intends to allow the lane change operation of the own vehicle α, and to determine whether to stop the lane change control linked to the result of the determination that there is no intention to allow the lane change operation. can do.

(Third Embodiment)
A third embodiment will be described below with reference to FIG. Elements similar to those of the first embodiment or the second embodiment are assigned the same reference numerals, and descriptions thereof are omitted. This embodiment differs from the second embodiment in the vehicle travel control method that uses the front vehicle acceleration Aβ as a factor for determining whether or not the lane change operation of the own vehicle α is permitted by the rear vehicle γ. Aspects are employed.

FIG. 7 is a flowchart showing the main determination mode in the vehicle travel control method of this embodiment. For the sake of simplification of the drawing, the steps (step S130, step S131, step S131' and step S131'') overlapping with FIG. 6 according to the second embodiment are omitted.

In the present embodiment, the controller 20 first performs steps S131, S131', and S131'' as in the second embodiment (not shown). Then, the controller 20 shifts to the determination of step S1341 through the affirmative results of the determinations of steps S132 and S133.

Then, in step S1341, the controller 20 determines whether or not the front vehicle acceleration Aβ is equal to or greater than a predetermined first front vehicle acceleration threshold Aβ_Th1.

Here, the first front vehicle acceleration threshold Aβ_Th1 is a suitable value from the viewpoint of determining whether or not the value of the front vehicle acceleration Aβ is large enough to encourage the rear vehicle γ to accelerate so that the distance X between vehicles does not become too large. is set to In particular, the first front vehicle acceleration threshold Aβ_Th1 is set to a positive value.

When the controller 20 determines that the front vehicle acceleration Aβ is equal to or greater than the first front vehicle acceleration threshold Aβ_Th1, the controller 20 proceeds to the determination of step S134' described in the second embodiment. Note that the processing after step S134' is the same as in the second embodiment.

On the other hand, when the controller 20 determines in step S1341 that the front vehicle acceleration Aβ is not equal to or greater than the first front vehicle acceleration threshold Aβ_Th1, the process proceeds to step S1342.

In step S1342, the controller 20 determines whether or not the front vehicle acceleration Aβ is less than a predetermined second front vehicle acceleration threshold Aβ_Th2.

Here, the second front vehicle acceleration threshold Aβ_Th2 is used to determine whether the value of the front vehicle acceleration Aβ is small enough for the rear vehicle γ to maintain or reduce the rear vehicle acceleration Aγ so that the distance X does not become too narrow. is set to a preferred value from In particular, the second front vehicle acceleration threshold Aβ_Th2 is set to a negative value.

When the controller 20 determines that the front vehicle acceleration Aβ is less than the second front vehicle acceleration threshold Aβ_Th2, the controller 20 proceeds to the determination of step S134' and executes the subsequent processing.

On the other hand, when it is determined that the front vehicle acceleration Aβ is not less than the second front vehicle acceleration threshold Aβ_Th, the process proceeds to step S134 described in the first embodiment. Note that the processing after step S134 is the same as in the first embodiment.

According to the vehicle travel control method of the present embodiment having the configuration described above, as in the second embodiment, the factors for determining whether or not the lane change operation of the host vehicle α is permitted by the following vehicle γ are: Forward vehicle acceleration Aβ can be used.

As a result, as in the second embodiment, even in a scene in which the forward vehicle β is accelerating and the rearward vehicle γ is accelerating to a certain extent regardless of whether or not the lane change operation of the own vehicle α is permitted, the rearward vehicle Whether or not γ permits entry of own vehicle α can be determined with higher accuracy.

(Fourth embodiment)
A fourth embodiment will be described below with reference to FIG. Elements similar to those in any one of the first to third embodiments are denoted by the same reference numerals, and descriptions thereof are omitted.

This embodiment determines whether or not the rear vehicle γ permits the lane change operation of the own vehicle α based on the rear vehicle acceleration Aγ in the first embodiment as a determination for determining whether to stop the lane change control. In addition, a determination is made from the viewpoint of whether or not the distance X between vehicles for changing lanes is secured based on the forward vehicle acceleration Aβ.

FIG. 8 is a flowchart showing the main determination mode of this embodiment.

In the present embodiment, the controller 20 first performs steps S131 and S131' as in the first embodiment. Furthermore, the controller 20 makes a positive determination result in steps S132 and S133, and a negative determination result in the determination of step S134 (determination that the rear vehicle acceleration Aγ is less than the first rear vehicle acceleration threshold value Aγ_Th1), The process proceeds to determination in step S1342.

In step S1342, the controller 20 determines whether or not the front vehicle acceleration Aβ is less than the second front vehicle acceleration threshold Aβ_Th2. As in the third embodiment, the second front vehicle acceleration threshold Aβ_Th2 is such that the rear vehicle γ maintains or reduces the rear vehicle acceleration Aγ so that the distance X does not become too narrow. This value is set from the viewpoint of determining whether or not

Then, when the controller 20 determines that the front vehicle acceleration Aβ is not less than the second front vehicle acceleration threshold Aβ_Th2, the controller 20 proceeds to step S135 to set the stop flag to "1", and similarly to the first embodiment, step S140. (See FIG. 2) The subsequent processing is executed. That is, the lane change control is stopped in step S160.

On the other hand, when the controller 20 determines that the front vehicle acceleration Aβ is less than the second front vehicle acceleration threshold Aβ_Th2, the process proceeds to step S1343.

In step S1343, the controller 20 determines whether or not the state in which the front vehicle acceleration Aβ is less than the second front vehicle acceleration threshold Aβ_Th2 continues for a predetermined time Δt.

When the controller 20 determines that the determination result in step S1343 is affirmative, the controller 20 proceeds to step S135, sets the stop flag to "1", and performs the steps after step S140 (see FIG. 2) as in the first embodiment. Execute the process. That is, the lane change control is stopped in step S160.

That is, in the present embodiment, when the determination result in step S1343 is affirmative, it is estimated that the distance between vehicles X may become narrow enough to hinder the lane change operation of the own vehicle α, and the lane change control is stopped. .

On the other hand, when the controller 20 determines that the determination result of step S1343 is negative, the controller 20 directly proceeds to the process of step S140.

That is, if the time period during which the front vehicle acceleration Aβ is less than the second front vehicle acceleration threshold value Aβ_Th2 is shorter than the predetermined time Δt, the decrease in the front vehicle acceleration Aβ will hinder the lane change operation of the vehicle α. It is assumed that X is not narrowing, and lane change control is continued.

If it is determined that the determination result in step S1343 is negative, the vehicle-to-vehicle distance Dv (determination in step S132) and the vehicle-to-vehicle distance increase amount ΔDv are determined again (determination in step S133). is affirmative, the process may proceed to step S140. As a result, even if the inter-vehicle distance Dv or the inter-vehicle distance increase amount ΔDv changes due to a factor other than the change in the forward vehicle acceleration Aβ while the predetermined time Δt elapses in the determination in step S1343, the subject vehicle Since it is possible to confirm again whether or not it is to the extent that the lane change operation of α is hindered, the safety of the lane change control can be further improved.

According to the vehicle travel control method of the present embodiment having the configuration described above, the following effects are obtained.

In the vehicle running control method of this embodiment, the controller 20 determines whether or not the front vehicle acceleration Aβ is less than a second front vehicle acceleration threshold Aβ_Th2, which is a predetermined front vehicle acceleration threshold (step S1342).

When the front vehicle acceleration Aβ is less than the second front vehicle acceleration threshold Aβ_Th2 and continues for a predetermined time Δt (Yes in step S1342 and Yes in step S1343), the controller 20 stops the lane change control (step S135, No in step S140 of FIG. 2, and step S160).

As a result, lane change control can be preferably stopped in a scene where the distance between vehicles X is expected to narrow to such an extent that the deceleration of the preceding vehicle β hinders the lane change operation of the own vehicle α. As a result, it is possible to further improve the accuracy of the decision to stop the lane change control.

Note that in step S1343 in the present embodiment, it is determined whether or not the state in which the front vehicle acceleration Aβ is less than the second front vehicle acceleration threshold Aβ_Th2 continues for the predetermined time Δt. However, instead of or together with this determination mode, it is also possible to employ a mode in which it is determined whether or not the state continues until the running distance of the host vehicle α at the parallel running position P1 reaches a predetermined distance. good.

(Fifth embodiment)
The fifth embodiment will be described below with reference to FIGS. 9 to 11. FIG. Elements similar to those in any one of the first to fourth embodiments are denoted by the same reference numerals, and descriptions thereof are omitted. In the vehicle travel control method of the present embodiment, the sub-determination mode is further executed when it is not determined in the main determination mode that the lane change control should be stopped, especially while based on the configuration of the first embodiment. be done.

FIG. 9 is a flowchart showing the overall lane change control according to this embodiment. As shown, also in this embodiment, the controller 20 executes the processes of steps S110 to S140 in the same manner as in the examples of FIGS. 2 and 4 of the first embodiment.

Then, when the determination result of step S140 is affirmative, that is, when the stop flag is set to "0" even after passing through the main determination mode, the controller 20 of the present embodiment enters the sub-determination mode in step S170. Transition.

FIG. 10 is a flow chart showing the sub-determination mode.

As shown in the figure, in step S171, the controller 20 performs a process of moving the host vehicle α to the next parallel running position P2 (hereinafter also referred to as "next parallel running position movement process").

FIG. 11 is a diagram schematically showing an example of the travel locus of the host vehicle α under the next parallel position movement processing. As shown, in the next parallel position movement process, the controller 20 moves the host vehicle α from the parallel position P1 where the main determination mode is executed to the next parallel position P2 closer to the adjacent lane La2.

Regarding the specific drive control for the host vehicle α in the next parallel running position movement process, a target lateral distance Dαγ′ smaller than the target lateral distance Dαγ in the parallel running process described in the third embodiment is set, It can be executed in the same manner as the parallel running process.

Returning to FIG. 10, the controller 20 proceeds to step S172 after executing the next parallel running position movement process in step S171.

In step S172, the controller 20 calculates the inter-vehicle distance Dv, the rear vehicle acceleration Aγ, and the inter-vehicle distance increase amount ΔDv in the same manner as in step S131 of FIG.

Next, the controller 20 makes determinations in steps S173 to S175. Then, if the results of these determinations are all affirmative, the controller 20 ends the sub-determination mode as it is and proceeds to the process of step S180 in FIG.

On the other hand, if any of the above determinations is negative, the controller 20 proceeds to the process of step S176. Details of each determination will be described below.

First, in step S173, the controller 20 determines whether or not the inter-vehicle distance Dv is greater than the inter-vehicle distance threshold Dv_Th2. The inter-vehicle distance threshold Dv_Th2 is set to a value equal to or greater than the inter-vehicle distance threshold Dv_Th1 used for the determination in step S132 of FIG. Here, the reason why the inter-vehicle distance threshold Dv_Th2 used in the sub determination mode is set to be equal to or greater than the inter-vehicle distance threshold Dv_Th1 used in the main determination mode will be described.

The sub-determination mode of the present embodiment is executed on the premise that the stop flag is not set to "1" in the main determination mode (on the premise that the inter-vehicle distance Dv≦the inter-vehicle distance threshold Dv_Th1).

The next parallel running position P2 where the host vehicle α is positioned when the sub determination mode is executed is closer to the adjacent lane La2 than the parallel running position P1 when the main determination mode is executed. Therefore, when the following vehicle γ recognizes the own vehicle α moving from the parallel running position P1 to the next parallel running position P2, if the backward vehicle γ has the intention of allowing the lane change operation of the own vehicle α, the distance X It is thought that running is performed so as to widen or at least maintain the

In consideration of this point, in the determination of step S173, the present embodiment sets an inter-vehicle distance threshold Dv_Th2 that is larger than the inter-vehicle distance threshold Dv_Th1 as the inter-vehicle distance threshold Dv. That is, when the host vehicle α enters the distance X between the forward vehicle β and the rearward vehicle γ, the judgment as to whether or not a sufficient inter-vehicle distance Dv is ensured is stricter than the judgment in step S132 in the main judgment mode. It will be executed conditionally.

Then, when the controller 20 determines that the inter-vehicle distance Dv is greater than the inter-vehicle distance threshold value Dv_Th1 in the determination of step S173, the process proceeds to step S174.

In step S174, the controller 20 determines whether or not the inter-vehicle distance increase amount ΔDv is greater than the inter-vehicle distance increase amount threshold value ΔDv_Th2. The vehicle distance increase threshold ΔDv_Th2 is set to a value equal to or less than the vehicle distance increase threshold ΔDv_Th1 used for the determination in step S133 of FIG.

Here, the reason why the vehicle distance increase threshold ΔDv_Th2 used in the sub determination mode is set to be equal to or less than the vehicle distance increase threshold ΔDv_Th1 used in the main determination mode will be described.

Since the host vehicle α is positioned at the next parallel running position P2 when the sub-judgment mode is executed, it is closer to the inter-vehicle distance X of the lane change destination than the parallel running position P1 when the main judgment mode is executed. be. Therefore, when the lane change operation is started from the state where the host vehicle α is positioned at the next parallel running position P2, compared to the case where it is started from the state where the own vehicle α is positioned at the parallel running position P1, the lane change operation from the start to the completion time is shorter. Therefore, in the sub-judgment mode, even if the inter-vehicle distance increase ΔDv is smaller than that in the main judgment mode and the inter-vehicle distance Dv tends to decrease to a certain degree, the distance X between the vehicles is increased to the extent that it interferes with the lane change operation of the vehicle α. It becomes easier to complete the lane change operation before the road narrows. For this reason, in the present embodiment, the sub-determination mode makes the determination of the inter-vehicle distance increase amount ΔDv under looser conditions than the main determination mode.

Further, in the present embodiment, while estimating a preferable inter-vehicle distance increase amount ΔDv from the viewpoint of the lane change operation of the host vehicle α, frequent cancellation decisions are made due to excessively strict determination of the inter-vehicle distance increase amount ΔDv. From the point of view of suppressing

Next, in step S175, the controller 20 determines whether or not the rear vehicle acceleration Aγ is smaller than the second rear vehicle acceleration threshold Aγ_Th2. The second rear vehicle acceleration threshold Aγ_Th2 is set to a value less than or equal to the first rear vehicle acceleration threshold Aγ_Th1 used for the determination in step S134 of FIG. That is, the second rear vehicle acceleration threshold Aγ_Th2 is set equal to or smaller than the first rear vehicle acceleration threshold Aγ_Th1.

Here, the reason why the second rear vehicle acceleration threshold Aγ_Th2 used in the sub determination mode is set to be equal to or less than the first rear vehicle acceleration threshold Aγ_Th1 used in the main determination mode is that the own vehicle α This is to check again under stricter conditions whether the following vehicle γ is willing to allow the lane change operation of the own vehicle α at the next parallel running position P2 closer to the lane La2.

In particular, in step S175, although it was determined in step S134 in the main determination mode that the rear vehicle acceleration Aγ was smaller than the first rear vehicle acceleration threshold Aγ_Th1, the rear vehicle γ actually changed lanes of the host vehicle α. It is done with the intention of preferably detecting when there is no intention to allow the movement.

More specifically, when the rear vehicle γ actually does not intend to allow the lane change operation of the own vehicle α, the own vehicle α moves from the parallel running position P1 to the next parallel running position P2 closer to the distance between the vehicles X. is recognized, a scene is assumed in which the rear vehicle γ accelerates in order to block the entry of the host vehicle α into the inter-vehicle distance X.

In this embodiment, the magnitude of the rear vehicle acceleration A.gamma. In particular, the determination in step S175 is executed at the next parallel running position P2, which is closer to the rear vehicle γ than the parallel running position P1. The threshold of Aγ is set strictly.

When the controller 20 determines that the rear vehicle acceleration Aγ is smaller than the second rear vehicle acceleration threshold Aγ_Th2 (No in step S175), the process proceeds to step S180 in FIG. On the other hand, when the controller 20 determines that the rear vehicle acceleration Aγ is greater than or equal to the second rear vehicle acceleration threshold Aγ_Th2 (Yes in step S175), the process proceeds to step S176.

In step S176, the controller 20 sets the stop flag indicating that the lane change control should be stopped to "1", and proceeds to the process of step S180 in FIG.

Then, returning to FIG. 9, in step S180, the controller 20 determines whether or not the stop flag is "0". Then, when the controller 20 determines that the stop flag is "0", it executes the process of step S150, and when it determines that the stop flag is "1", it executes the process of step S160. Note that each process of step S150 and step S160 is the same as that of the first embodiment.

According to the vehicle travel control method of the present embodiment having the configuration described above, the following effects are obtained.

In the vehicle running control method of the present embodiment, when it is further determined that the rear vehicle acceleration Aγ is smaller than the first rear vehicle acceleration threshold Aγ_Th1 (Yes in step S130 in FIG. 9 and step S134 in FIG. 5), the host vehicle α is moved to the next parallel running position P2 closer to the adjacent lane La2 than the parallel running position P1 (step S171 in FIG. 10). When it is determined that the rear vehicle acceleration Aγ is greater than or equal to the predetermined second rear vehicle acceleration threshold Aγ_Th2 (No in step S175 of FIG. 10) with the host vehicle α positioned at the next parallel running position P2, Stop lane change control (step S176 in FIG. 10, No in step S180 in FIG. 9, and step S160).

As described above, in the present embodiment, when the own vehicle α is positioned at the parallel running position P1, the first stage determination (step S134 in the main determination mode) is performed based on the rear vehicle acceleration Aγ for determining whether to stop the lane change control. is executed, and in a state in which the host vehicle α is positioned at the next parallel running position P2 closer to the adjacent lane La2, the second stage determination ( Step S175) in the sub-determination mode is executed.

Therefore, the rear vehicle acceleration Aγ is determined to be smaller than the first rear vehicle acceleration threshold value Aγ_Th1 in the determination of the first stage even though the rear vehicle γ does not actually allow the lane change operation of the own vehicle α. Even if it is, it can be detected in the second step determination. That is, it is possible to further improve the determination accuracy based on the rear vehicle acceleration Aγ regarding whether or not the rear vehicle γ permits the lane change operation of the own vehicle α.

In particular, although the occupants of the rear vehicle γ intend to deny the vehicle α from entering the inter-vehicle distance X for the lane change operation, the vehicle α moves to the parallel running position P1 which is somewhat distant from the adjacent lane La2. Acceleration operation may not be performed in the positioned state. On the other hand, it is assumed that the occupants and the like of the rear vehicle γ will start an acceleration operation by recognizing the movement of the own vehicle α to the next parallel running position P2 closer to the adjacent lane La2.

With the configuration of the vehicle running control method according to the present embodiment, due to such factors, the acceleration of the rear vehicle γ that starts after the own vehicle α approaches the adjacent lane La2 from the side-by-side running position P1 is also affected by the lane change control. It can be used as a determination element related to the cancellation determination.

Furthermore, in this embodiment, the second rear vehicle acceleration threshold Aγ_Th2 is set to a value smaller than the first rear vehicle acceleration threshold Aγ_Th1.

As a result, in the determination of the second stage, the reference of the rear vehicle acceleration Aγ for determining the suspension of the lane change control becomes stricter than in the determination of the first stage. As a result, the safety when the lane change operation of the own vehicle α is performed is more preferably ensured.

(Sixth embodiment)
The sixth embodiment will be described below with reference to FIGS. 12 and 13. FIG. Elements similar to those in any one of the first to fifth embodiments are denoted by the same reference numerals, and description thereof will be omitted. In this embodiment, in addition to the vehicle running control method having the configuration of any one of the first to fifth embodiments, a stop position determination mode is executed.

In the stop position determination mode, it is determined whether or not the own vehicle α traveling in the driving lane La1 is approaching the lane change prohibited section A, and lane change control is performed when it is determined that the vehicle is approaching the lane change prohibited section A by a certain degree. cancel. The details are described below.

FIG. 12 is a flow chart showing the stop position determination mode. Note that the controller 20 of this embodiment executes the following stop position determination mode in parallel with the lane change control in FIG. 2 or 9 .

As shown, first, in step S210, the controller 20 determines whether or not there is a lane change prohibition sign S indicating a lane change prohibition section A on the driving lane La1.

More specifically, the controller 20 determines that the lane change prohibition sign S exists in the driving lane La1 based on at least one of the image captured by the vehicle-mounted camera 1a of the external sensor 1 and the navigation information Ina from the navigation system 3. Determine whether or not

When the controller 20 determines whether or not the lane change prohibition sign S is present on the driving lane La1 based on the navigation information Ina, the controller 20 determines whether the lane change prohibition sign S indicated by the navigation information Ina and the own vehicle α If the remaining distance L between and is within a range that has a realistic influence from the viewpoint of executing the lane change stop determination, it is determined that the lane change prohibition sign S exists.

On the other hand, the controller 20 determines that the remaining distance L between the lane change prohibition sign S indicated in the navigation information Ina and the host vehicle α has no practical effect from the viewpoint of executing the judgment to stop changing the lane. is large (for example, 1 km or more), it is determined that the lane change prohibition sign S does not exist.

Then, when the controller 20 determines that the lane change prohibition sign S exists, the process proceeds to step S220.

In step S220, the controller 20 calculates the remaining distance L between the host vehicle α and the lane change prohibition sign S. Specifically, the controller 20 calculates the remaining distance L based on the information of the lane change prohibition sign S detected by the radar 1 b of the external sensor 1 .

Next, in step S230, the controller 20 determines whether or not the calculated remaining distance L is greater than a predetermined threshold distance L_th.

Here, the threshold distance L_th is determined from the viewpoint of whether or not the remaining distance L is such that the own vehicle α enters the lane change prohibited section A before the lane change operation of the own vehicle α is completed. In particular, the threshold distance L_th can be appropriately determined according to any parameter (vehicle speed Vα, etc.) that affects the distance traveled by the vehicle α until the lane change operation is completed. For example, the threshold distance L_th can be set to approximately the same to three times the length of the host vehicle α.

When the controller 20 determines that the remaining distance L is equal to or less than the threshold distance L_th in step S230, the process of step S240 is executed.

In step S240, the controller 20 executes lane change stop processing. Note that the specific content of the lane change stop processing is the same as the processing described in step S160 of FIG.

Note that in the present embodiment, when it is determined that the remaining distance L is equal to or less than the threshold distance L_th in step S230, the controller 20 gives priority to the lane change control in FIG. 2 or 9 described above. Execute lane change stop processing.

Next, a specific scene in which the stop position determination mode described above is executed will be described.

FIG. 13 is a diagram illustrating an example of a specific scene in which the stop position determination mode is executed.

In particular, FIG. 13 shows a state in which the intersection CP is approaching the lane La1 of the own vehicle α. That is, in this example, it is assumed that the host vehicle α is approaching the lane change prohibition section A set around the intersection CP on the driving lane La1.

In this case, when the remaining distance L between the own vehicle α and the lane change prohibition sign S representing the lane change prohibition section A (the solid center line between the driving lane La1 and the adjacent lane La2) is equal to or less than the threshold distance L_th. At this time, the lane change control of the own vehicle α is stopped.

According to the vehicle travel control method of the present embodiment having the configuration described above, the following effects are obtained.

In the vehicle running control method of the present embodiment, when the remaining distance L between the own vehicle α and the lane change prohibited section A is equal to or less than the predetermined threshold distance L_th (Yes in step S230 of FIG. 12), lane change control is performed. (Step S240 in FIG. 12).

As a result, it is possible to prevent the vehicle α from entering the lane change prohibited section A during the lane change operation.

In particular, as already described, the configuration of the vehicle travel control method of the first embodiment, which is the premise of the present embodiment, achieves the effect of being able to quickly determine whether to stop the lane change control. As a result, even if the lane change control of the own vehicle α is stopped, the chances of searching for the timing at which the next lane change can be executed by the reroute processing described above increase.

Therefore, even if the lane change control is stopped when the remaining distance L to the lane change prohibited section A becomes equal to or less than the threshold distance L_th as in the present embodiment, the lane change is finally completed. It is possible to increase the possibility that the lane change operation of the own vehicle α can be completed by the desired point (for example, the intersection CP) where it is necessary.

In addition, from the viewpoint of more reliably suppressing a situation in which the host vehicle α enters the lane change prohibited section A during lane change control, the threshold distance L_th can be set relatively large. Even when the threshold distance L_th is set relatively large in this manner, the reroute processing increases the chances of searching for the timing at which the next lane change can be performed, so that the vehicle α can reach the desired point. The function of satisfying the request to complete the lane change operation can be favorably exhibited.

Although the embodiments of the present invention have been described above, the above-described embodiments and modifications merely show a part of the application examples of the present invention, and the technical scope of the present invention is limited to the specific configurations of the above-described embodiments. It is not intended to be limited to

In each of the above embodiments, the values (inter-vehicle distance Dv, rear vehicle acceleration Aγ, etc.) calculated by the controller 20 may be values for one cycle (instantaneous values) according to the set calculation cycle, or may be calculated for a predetermined period of time. It may be an average value of a plurality of instantaneous values over a period of time.

The controller 20 also controls the movement of the own vehicle α from the normal running position P0 to the parallel running position P1 (parallel running processing in FIG. 3) and the movement of the vehicle α from the parallel running position P1 to the next parallel running position P2 (next running position P2). parallel running position movement control), and when the own vehicle α enters the space X between the front vehicle β and the rear vehicle γ (lane change operation), drive so that the own vehicle α performs each operation while decelerating. Manipulation and steering maneuvers may be performed. For example, in the parallel running process, by setting the basic control value set for the front-rear target position Lαγ to be larger than "Dv/2" (see formula (1)) in the above embodiment, the own vehicle α is decelerated while each Actions can be performed.

5 to 8 and the sub-determination mode described with reference to FIG. may be corrected according to the size of .

In particular, when the inter-vehicle distance DV is sufficiently large, a scene is assumed in which the own vehicle α can change lanes without executing the determination of the rear vehicle acceleration Aγ. For such a scene, the first rear vehicle acceleration threshold Aγ_Th1, the corrected first rear vehicle acceleration threshold Aγ_Th1 (Aβ ), or the second rear vehicle acceleration threshold value Aγ_Th2 can be corrected as appropriate. Further, the inter-vehicle distance threshold Dv_Th1 or the inter-vehicle distance increase threshold ΔDv_Th2 used in determining the inter-vehicle distance increase amount ΔDv can also be corrected in the same manner.

Furthermore, the above-described embodiments can be combined with each other in arbitrary combinations within a range that does not cause contradiction. In particular, the combination of the configuration of any one of the first to fourth embodiments and the configuration of the fifth or sixth embodiment, and the combination of the configuration of the fifth embodiment and the configuration of the sixth embodiment are It is possible.

Furthermore, the vehicle running control program for causing the controller 20, which is a computer, to execute the vehicle running control method described in each of the above embodiments, and the storage medium storing the vehicle running control program are also disclosed in the specification as of the filing of this application. It is included within the scope of the matters described in, etc.

In addition, the controller 20 in the vehicle travel control method in each of the above embodiments may be configured by a single computer, or may be configured by a plurality of computers that perform distributed processing of each step of the vehicle travel control method. . Furthermore, in each of the above-described embodiments, an example has been described in which the functions of the controller 20 are realized by the ECU mounted on the own vehicle α. However, the controller 20 can be realized by any control device other than the ECU mounted on the vehicle α. Furthermore, at least part of the functions of the controller 20 that executes each step of the vehicle travel control method in each of the above embodiments may be executed by any external computer that communicates with the control device within the own vehicle α.

REFERENCE SIGNS LIST 1 external sensor 1a onboard camera 1b radar 2 internal sensor 2a vehicle speed sensor 2b acceleration sensor 2c yaw rate sensor 3 navigation system 4 actuator 4a drive actuator 4b brake actuator 4c steering actuator 10 vehicle travel control system 20 controller

Claims (8)

A vehicle travel control method in which a controller executes lane change control for allowing a vehicle traveling in a travel lane to enter between vehicles traveling in an adjacent lane,
When the lane change control is started , identifying a vehicle located behind the own vehicle in the adjacent lane,
When the rear vehicle is specified, the own vehicle is moved from the running position in the running lane to a parallel running position closer to the adjacent lane,
obtaining a rear vehicle acceleration, which is the acceleration of the rear vehicle after the host vehicle has moved to the parallel running position;
When it is determined that the rear vehicle acceleration is greater than or equal to a predetermined first rear vehicle acceleration threshold, the lane change control is stopped;
A vehicle travel control method. The vehicle running control method according to claim 1,
correcting such that the first rear vehicle acceleration threshold increases as the front vehicle acceleration, which is the acceleration of the front vehicle of the vehicle, increases;
A vehicle travel control method. The vehicle travel control method according to claim 1, further comprising:
determining whether a forward vehicle acceleration, which is the acceleration of the forward vehicle among the vehicles, is less than a predetermined forward vehicle acceleration threshold;
stopping the lane change control when it is determined that the state in which the forward vehicle acceleration is less than the forward vehicle acceleration threshold continues for a predetermined period of time;
A vehicle travel control method. The vehicle travel control method according to any one of claims 1 to 3, further comprising:
when it is determined that the rear vehicle acceleration is smaller than the first rear vehicle acceleration threshold, moving the own vehicle to a next parallel running position closer to the adjacent lane than the parallel running position;
stopping the lane change control when it is determined that the rear vehicle acceleration is greater than or equal to a predetermined second rear vehicle acceleration threshold in the state in which the own vehicle is positioned at the next parallel running position;
A vehicle travel control method. The vehicle travel control method according to claim 4,
setting the second rear vehicle acceleration threshold to a value smaller than the first rear vehicle acceleration threshold;
A vehicle travel control method. The vehicle travel control method according to any one of claims 1 to 5, further comprising:
If it is determined that the remaining distance between the own vehicle and the lane change prohibited section is equal to or less than a predetermined threshold distance, the lane change control is stopped.
A vehicle travel control method. The vehicle travel control method according to any one of claims 1 to 6,
If the lane change control is stopped, searching for an opportunity to perform the lane change control again;
A vehicle travel control method. A vehicle travel control system that executes lane change control for allowing a vehicle traveling in a travel lane to enter between vehicles traveling in an adjacent lane,
an external sensor that detects position information of each of the vehicles;
an internal sensor that detects the vehicle speed and acceleration of the host vehicle;
an actuator for driving and steering the own vehicle;
a controller that operates the actuator based on values detected by the external sensor and the internal sensor;
The controller is
Upon receiving a lane change request, starting the lane change control,
When the lane change control is started, causing the own vehicle to run parallel to the vehicle in the adjacent lane at a position parallel to the driving lane,
Acquiring the position information of the vehicle and the vehicle speed and acceleration of the vehicle from the external sensor and the internal sensor, respectively, while the vehicle is traveling side by side;
calculating a rear vehicle acceleration, which is the acceleration of a rear vehicle in the vehicle, based on the position information of the vehicle and the vehicle speed and acceleration of the own vehicle;
determining whether the rear vehicle acceleration is greater than or equal to a predetermined first rear vehicle acceleration threshold;
If the result of the determination is affirmative, canceling the lane change control;
Vehicle cruise control system.

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