JP7690785B2 - Lane changing device - Google Patents

Description

The present invention relates to a lane changing device.

Lane change devices that automatically change the lane of the vehicle to an adjacent lane are known. Also known are lane change devices in which the time from when the lane change of the vehicle begins to when the lane change is completed (lane change time) is set so that the lane change of the vehicle can be completed within a certain time. Furthermore, as such lane change devices, there are also known lane change devices that are configured to change the lane change time when there is a vehicle (following vehicle) approaching the vehicle in the adjacent lane into which the vehicle is about to change lanes, in order to reduce the driver's anxiety about the lane change of the vehicle and to safely change lanes of the vehicle (see, for example, Patent Document 1).

JP 2020-35100 A

Conventional lane change devices detect the following vehicle based on information obtained from a radar sensor, camera sensor, or the like mounted on the vehicle. However, due to the detection and detection capabilities of the radar sensor, camera sensor, or the like, it may not be possible to detect the following vehicle if it is traveling away from the vehicle. Furthermore, if the following vehicle is approaching the vehicle at high speed, if the vehicle starts to change lanes just because the following vehicle has not been detected, the following vehicle may catch up with the vehicle before the vehicle has completed its lane change. In this case, for example, the lane change of the vehicle may have to be canceled.

The object of the present invention is to provide a lane change device that can reliably complete lane changes of the vehicle even when there is a vehicle approaching the vehicle from behind at high speed.

A lane change device according to the present invention is a device that executes lane change control to change a host vehicle to an adjacent lane. The lane change device according to the present invention estimates a following vehicle catch-up possibility that a following vehicle traveling in an adjacent lane that is approaching the host vehicle from behind the host vehicle and that causes the host vehicle to change lanes by the lane change control will catch up with the host vehicle. The lane change device according to the present invention sets a target lane change time, which is a target time from when the host vehicle starts to change lanes by the lane change control to when the host vehicle completes the lane change to the adjacent lane, to a shorter time as the following vehicle catch-up possibility increases, and performs lane change of the host vehicle to the adjacent lane by the lane change control so that the lane change to the adjacent lane is completed within the set target lane change time.
Furthermore, the host vehicle is equipped with a surrounding information detection device that detects information about the surroundings of the host vehicle. When a first condition is satisfied that the following vehicle does not exist and the detection accuracy of the surrounding information detection device is equal to or lower than a predetermined accuracy, the lane changing device according to the present invention determines that the following vehicle is likely to catch up with the host vehicle, and when it is determined that the following vehicle is likely to catch up with the host vehicle due to the satisfaction of the first condition, adds a predetermined first numerical value as a following vehicle catch-up possibility level that is a level indicating the possibility of the following vehicle catching up, and sets the target lane changing time to a shorter time as the following vehicle catch-up possibility level is higher.

According to this, the higher the possibility of catching up with the following vehicle, the shorter the target lane change time is set, and the host vehicle is changed to the adjacent lane by lane change control so that the lane change is completed within the target lane change time. Therefore, the host vehicle can reliably complete the lane change even when there is a following vehicle approaching the host vehicle at high speed.
Furthermore, the lane changing device of the present invention may be configured to determine that there is a possibility that the following vehicle will catch up with the host vehicle when a second condition is met that the following vehicle is not present and the traveling speed of the host vehicle is slower than a first speed by more than the regulated speed applied to the host vehicle, and to add a predetermined second numerical value as the possibility level of the following vehicle catching up when it is determined that there is a possibility that the following vehicle will catch up with the host vehicle due to the second condition being met.
Furthermore, the lane changing device of the present invention may be configured to determine that there is a possibility that the following vehicle will catch up with the host vehicle when a third condition is met that the following vehicle is not present and the distance between the congestion location ahead of the host vehicle and the host vehicle is less than a predetermined distance, and to add a predetermined third numerical value as the possibility level of the following vehicle catching up when it is determined that there is a possibility that the following vehicle will catch up with the host vehicle due to the third condition being met.
Furthermore, the lane changing device of the present invention may be configured to determine that there is a possibility that the rear vehicle will catch up with the host vehicle when a fourth condition is met that the rear vehicle is not present and the traveling speed of the host vehicle is at least a second speed faster than the traveling speed of the leading vehicle, and to add a predetermined fourth numerical value as the possibility level of the rear vehicle catching up when it is determined that there is a possibility that the rear vehicle will catch up with the host vehicle due to the fourth condition being met.
Furthermore, the lane changing device of the present invention may be configured to determine that there is a possibility that the following vehicle will catch up with the host vehicle when a fifth condition is met that there is no following vehicle, the host vehicle is traveling in a driving lane, and the adjacent lane is an overtaking lane, and to add a predetermined fifth numerical value as the following vehicle overtaking possibility level when it is determined that there is a possibility that the following vehicle will catch up with the host vehicle due to the fifth condition being met.

The components of the present invention are not limited to the embodiments of the present invention described below with reference to the drawings. Other objects, other features and associated advantages of the present invention will be easily understood from the description of the embodiments of the present invention.

FIG. 1 is a diagram showing a lane changing device according to an embodiment of the present invention and a vehicle (host vehicle) equipped with the lane changing device. FIG. 2 is a diagram showing a situation in which the host vehicle is changing lanes. FIG. 3 is a diagram showing a scene in which a vehicle is traveling alongside the host vehicle. FIG. 4 is a diagram showing a situation in which a following vehicle is present behind the host vehicle. FIG. 5 is a diagram showing a target lane change path. FIG. 6 is a diagram showing a scene where a vehicle ahead is present ahead of the host vehicle. FIG. 7 is a diagram showing a lane change from a driving lane to an overtaking lane. FIG. 8 is a flowchart showing a routine executed by the lane changing device according to the embodiment of the present invention. FIG. 9 is a flowchart showing a routine executed by the lane changing device according to the embodiment of the present invention. FIG. 10 is a flowchart showing a routine executed by the lane changing device according to the embodiment of the present invention. FIG. 11 is a flowchart showing a routine executed by the lane changing device according to the embodiment of the present invention. FIG. 12 is a flowchart showing a routine executed by the lane changing device according to the embodiment of the present invention.

The following describes a lane changing device according to an embodiment of the present invention with reference to the drawings. As shown in FIG. 1, a lane changing device 10 according to an embodiment of the present invention is mounted on a vehicle 100. In the following description, the driver of the vehicle 100 is referred to as "driver DR."

<ECU>
The lane changing device 10 includes an ECU 90. ECU is an abbreviation for electronic control unit. The ECU 90 includes a microcomputer as a main component. The microcomputer includes a CPU, a ROM, a RAM, a non-volatile memory, an interface, and the like. The CPU is configured to realize various functions by executing instructions, programs, or routines stored in the ROM.

<Running gear>
The host vehicle 100 is also equipped with a traveling device 20. The traveling device 20 includes a drive device 21, a braking device 22, and a steering device 23.

<Drive unit>
The drive device 21 is a device that outputs a drive torque (drive force) applied to the host vehicle 100 to make the host vehicle 100 travel, and is, for example, an internal combustion engine, a motor, etc. The drive device 21 is electrically connected to the ECU 90. The ECU 90 can control the drive torque output from the drive device 21 by controlling the operation of the drive device 21.

<Brake device>
The braking device 22 is a device, such as a brake device, that outputs a braking torque (braking force) applied to the host vehicle 100 in order to brake the host vehicle 100. The braking device 22 is electrically connected to the ECU 90. The ECU 90 can control the braking torque output from the braking device 22 by controlling the operation of the braking device 22.

<Steering device>
The steering device 23 is a device that outputs a steering torque (steering force) applied to the host vehicle 100 in order to steer the host vehicle 100, and is, for example, a power steering device. The steering device 23 is electrically connected to the ECU 90. The ECU 90 can control the steering torque output from the steering device 23 by controlling the operation of the steering device 23.

<Sensors, etc.>
Furthermore, the vehicle 100 is equipped with an accelerator pedal 31, an accelerator pedal operation amount sensor 32, a brake pedal 33, a brake pedal operation amount sensor 34, a steering wheel 35, a steering shaft 36, a steering angle sensor 37, a steering torque sensor 38, a lane keeping request switch 41, a lane change request switch 42, a vehicle speed detection device 51, a GPS device 52, a surrounding information detection device 60 and a road information detection device 70.

<Accelerator pedal operation amount sensor>
The accelerator pedal operation amount sensor 32 is a sensor that detects the operation amount of the accelerator pedal 31, and is electrically connected to the ECU 90. The accelerator pedal operation amount sensor 32 transmits information on the detected operation amount of the accelerator pedal 31 to the ECU 90. The ECU 90 acquires the operation amount of the accelerator pedal 31 as the accelerator pedal operation amount AP based on that information. When lane change control, which will be described later, is not being executed, the ECU 90 executes normal driving control. During execution of the normal driving control, the ECU 90 acquires a required driving torque (required driving force) based on the accelerator pedal operation amount AP and the host vehicle speed V100 (the traveling speed of the host vehicle 100), and controls the operation of the drive device 21 so that the required driving torque is output from the drive device 21.

<Brake pedal operation amount sensor>
The brake pedal operation amount sensor 34 is a sensor that detects the operation amount of the brake pedal 33, and is electrically connected to the ECU 90. The brake pedal operation amount sensor 34 transmits information on the detected operation amount of the brake pedal 33 to the ECU 90. The ECU 90 acquires the operation amount of the brake pedal 33 as the brake pedal operation amount BP based on the information. As described above, when the lane change control described later is not being executed, the ECU 90 executes the normal driving control. During the execution of the normal driving control, the ECU 90 acquires a required braking torque (required braking force) based on the brake pedal operation amount BP, and controls the operation of the braking device 22 so that the required braking is output from the braking device 22.

<Steering angle sensor>
The steering angle sensor 37 is a sensor that detects the rotation angle of the steering shaft 36 with respect to the neutral position, and is electrically connected to the ECU 90. The steering angle sensor 37 transmits information on the detected rotation angle of the steering shaft 36 to the ECU 90. The ECU 90 obtains the rotation angle of the steering shaft 36 as a steering angle θs based on the information.

<Steering torque sensor>
The steering torque sensor 38 is a sensor that detects the torque input by the driver DR to the steering shaft 36 via the steering wheel 35, and is electrically connected to the ECU 90. The steering torque sensor 38 transmits information on the detected torque to the ECU 90. The ECU 90 acquires the torque (driver input torque) input by the driver DR to the steering shaft 36 via the steering wheel 35 based on the information. As described above, when the lane change control described later is not being executed, the ECU 90 executes the normal driving control. During the execution of the normal driving control, the ECU 90 acquires a required steering torque based on the steering angle θs, the driver input torque, and the vehicle speed V100 (the traveling speed of the vehicle 100), and controls the operation of the steering device 23 so that the required steering torque is output from the steering device 23.

<Lane keeping request switch>
The lane keeping request switch 41 is a switch that is operated by the driver DR to request the execution of lane keeping control, which will be described later, and is electrically connected to the ECU 90. When the lane keeping request switch 41 is operated to the ON position, the ECU 90 determines that the execution of lane keeping control has been requested.

<Lane change request switch>
The lane change request switch 42 is a switch operated by the driver DR to request execution of lane change control described later, and is, for example, a turn signal lever operated by the driver DR to blink the direction indicator of the host vehicle 100. The lane change request switch 42 is electrically connected to the ECU 90. When the lane change request switch 42 is operated and set to a position requesting a lane change to an adjacent lane on the right side of the driving lane (host lane LN_O) of the host vehicle 100, the ECU 90 determines that execution of lane change control for changing the host vehicle 100 to the adjacent lane on the right side of the host lane LN_O has been requested, and when the lane change request switch 42 is operated and set to a position requesting a lane change to an adjacent lane on the left side of the host lane LN_O, the ECU 90 determines that execution of lane change control for changing the host vehicle 100 to the adjacent lane on the left side of the host lane LN_O has been requested. When the lane change request switch 42 is a turn signal lever, the ECU 90 determines that, when the turn signal lever is operated in a clockwise direction for a predetermined period of time, the execution of lane change control has been requested to change the lane of the vehicle 100 to the adjacent lane to the right of the vehicle's lane LN_O, and determines that, when the turn signal lever is operated in a counterclockwise direction for a predetermined period of time, the execution of lane change control has been requested to change the lane of the vehicle 100 to the adjacent lane to the left of the vehicle's lane LN_O.

<Vehicle speed detection device>
The vehicle speed detection device 51 is a device that detects the vehicle speed (host vehicle speed V100) of the host vehicle 100, and is, for example, a wheel speed sensor. The vehicle speed detection device 51 is electrically connected to the ECU 90. The vehicle speed detection device 51 transmits information on the detected vehicle speed of the host vehicle 100 to the ECU 90. The ECU 90 acquires the host vehicle speed V100 based on the information.

<GPS device>
The GPS device 52 is a device that receives so-called GPS signals, and is electrically connected to the ECU 90. The ECU 90 acquires the GPS signals via the GPS device 52. The ECU 90 can acquire a current position P100 of the host vehicle 100 based on the acquired GPS signals.

<Peripheral information detection device>
The surrounding information detection device 60 is a device that detects information about the surroundings of the vehicle 100, and in this example, includes a radio wave sensor 61 and an image sensor 62. The radio wave sensor 61 is, for example, a radar sensor (such as a millimeter wave radar). The image sensor 62 is, for example, a camera. The surrounding information detection device 60 may also include a sonic sensor such as an ultrasonic sensor (clearance sonar) or an optical sensor such as a laser radar (LiDAR).

<Radio wave sensor>
The radio wave sensor 61 is electrically connected to the ECU 90. The radio wave sensor 61 transmits radio waves and receives radio waves (reflected waves) reflected by objects. The radio wave sensor 61 transmits information (detection results) related to the transmitted radio waves and received radio waves (reflected waves) to the ECU 90. In other words, the radio wave sensor 61 detects objects present in the vicinity of the vehicle 100 and transmits information (detection results) related to the detected objects to the ECU 90. The ECU 90 can obtain information (periphery detection information IS) related to objects present in the vicinity of the vehicle 100 based on the information (radio wave information). In this example, the objects are vehicles, motorcycles, bicycles, people, etc.

<Image sensor>
The image sensor 62 is also electrically connected to the ECU 90. The image sensor 62 captures an image of the periphery of the vehicle 100 and transmits information related to the captured image to the ECU 90. The ECU 90 can obtain information (periphery detection information IS) related to the periphery of the vehicle 100 based on the information (camera image information).

<Road Information Detection Device>
The road information detection device 70 includes a receiving device 71 and a map information database 72 .

<Receiving device>
The receiving device 71 is a device that receives a wireless signal from the outside, and is electrically connected to the ECU 90. The ECU 90 acquires the wireless signal from the outside via the receiving device 71.

<Map information database>
The map information database 72 is a database that stores map information including "information regarding speed limits" and "information regarding road types", and is electrically connected to the ECU 90. The ECU 90 can obtain information regarding the speed limit currently applied to the vehicle 100 and the type of road on which the vehicle 100 is currently traveling, from the current position P100 of the vehicle 100.

<Outline of lane change device operation>
Next, an overview of the operation of the lane change device 10 will be described.

<Lane change control>
When execution of lane change control is requested, the lane change device 10 executes lane change control on the condition that a prohibition condition CF described later is not satisfied. In this example, execution of lane keeping control is not a condition for executing lane change control, but it may be a condition. The lane keeping control is a control for maintaining the running of the host vehicle 100 in the host lane LN_O by recognizing the center line of the host lane LN_O based on the surrounding detection information IS and steering the host vehicle 100 so that the host vehicle 100 runs along the center line. The center line of the host vehicle 100 can be recognized based on the surrounding detection information IS.

As shown in FIG. 2, lane change control is a control that includes a lane change driving process that automatically changes the vehicle 100 to a lane next to the vehicle's lane LN_O (adjacent lane). Note that FIG. 2 shows a scene in which execution of lane change control is requested to change the vehicle 100 to an adjacent lane (second lane LN2 in the example shown in FIG. 2) to the right of the vehicle's lane LN_O (first lane LN1 in the example shown in FIG. 2). The lane change device 10 recognizes the vehicle's lane LN_O and the adjacent lanes based on the surrounding detection information IS. Note that in FIG. 2, the symbol LN3 indicates the lane adjacent to the right of the second lane LN2.

The following describes the lane change control executed by the lane change device 10. In the following description, the lane adjacent to the own lane LN_O to which the own vehicle 100 is to be changed by the lane change control is referred to as the "target lane LN_T."

When lane change control is requested while lane keeping control is being performed, the lane change device 10 starts lane change control. When lane change control is started, the lane change device 10 first determines whether or not the prohibition condition CF is satisfied. The prohibition condition CF is a condition that is satisfied when it is determined that the lane change of the vehicle 100 cannot be performed safely in consideration of the situation around the vehicle 100.

In this example, the prohibition condition CF is satisfied when a parallel running vehicle 200 is present in the target lane LN_T (the second lane LN2 in the example shown in FIG. 3) as shown in FIG. 3. In this example, the parallel running vehicle 200 is another vehicle that is present within a predetermined range AR set on the target lane LN_T side of the vehicle 100. The predetermined range AR is a rectangular range on the horizontal plane, the width of which is equal to the width of the target lane LN_T, and the length of which is longer than the overall length of the vehicle 100. If another vehicle is present within this range, the other vehicle is estimated to hinder a safe lane change from the vehicle lane LN_O to the target lane LN_T. The lane changing device 10 recognizes the parallel running vehicle 200 based on the surrounding detection information IS.

When the lane change device 10 determines that the prohibition condition CF is satisfied, it ends the lane change control. In this case, the lane change driving process is not performed, and therefore the host vehicle 100 does not change lanes to the target lane LN_T.

On the other hand, if the lane changing device 10 determines that the prohibition condition CF is not satisfied, it determines whether or not the following vehicle 200R is present in the target lane LN_T. In this example, the following vehicle 200R is another vehicle present behind the host vehicle 100, as shown in FIG. 4. The lane changing device 10 recognizes the following vehicle 200R based on the surrounding detection information IS. At this time, since the prohibition condition CF is not satisfied, the lane changing device 10 is essentially determining whether or not the following vehicle 200R, which is not present within the specified range AR, is present in the target lane LN_T.

When a following vehicle 200R is present, the lane change device 10 sets the target lane change time TLCtgt to the reference time TLCbase. The target lane change time TLCtgt is the time required for the host vehicle 100 to complete a lane change to the target lane LN_T after starting the lane change driving process.

When the lane change device 10 sets the target lane change time TLCtgt, it sets the route along which the vehicle 100 will travel in order to complete the lane change within the target lane change time TLCtgt as the target lane change route Rtgt, as shown in FIG. 5.

When the lane change device 10 sets the target lane change route Rtgt, it starts a lane change driving process that controls the operation of the driving device 20 so that the vehicle 100 travels along the target lane change route Rtgt.

When the lane change of the vehicle 100 is completed, the lane change device 10 ends the lane change driving process, thereby ending the lane change control. In this example, when the lane change control is ended, the lane keeping control is started.

On the other hand, if there is no following vehicle 200R, it may be thought that the vehicle 100 can safely change lanes to the target lane LN_T by setting the reference time TLCbase to the target lane change time TLCtgt and starting the lane change driving process. However, for the following reasons, the lane change device 10 sets the target lane change time TLCtgt according to the following vehicle catch-up probability level LVrsk and executes the lane change driving process.

That is, in a situation where a following vehicle 200R is traveling at high speed in the target lane LN_T approaching the vehicle 100, but is traveling very far away from the vehicle 100, the following vehicle 200R is not detected by the surrounding information detection device 60, and the lane change device 10 therefore determines that the following vehicle 200R is not present. In such a situation, if the reference time TLCbase is set to the target lane change time TLCtgt and lane change driving processing is started just because the following vehicle 200R is not present, the following vehicle 200R will catch up with the vehicle 100 before the vehicle 100 has completed its lane change to the target lane LN_T, and the lane change driving processing that was once started must be stopped to ensure the safety of the vehicle 100.

For example, if the vehicle speed V100 is slower than the regulation speed Vreg applied to the vehicle 100 at that time by a certain speed or more, if the lane change driving process is started just because the following vehicle 200R is not present, the vehicle 100 may be caught up with the following vehicle 200R before the vehicle 100 completes the lane change. Therefore, if the vehicle speed V100 is slower than the regulation speed Vreg applied to the vehicle 100 at that time by a certain speed (first speed V1) or more, after the lane change driving process is started, the lane change device 10 determines that the following vehicle 200R may catch up with the vehicle 100 before the vehicle 100 completes the lane change. In other words, the lane change device 10 determines that the following vehicle 200R may be detected and the cancellation condition Ccan may be established before the vehicle 100 completes the lane change after the lane change driving process is started.

In this example, if the host vehicle speed V100 is slower than the regulation speed Vreg applied to the host vehicle 100 at that time by at least a first speed V1, the possibility that the following vehicle 200R will catch up with the host vehicle 100 before the host vehicle 100 completes its lane change is quantified in advance. Then, when the lane changing device 10 determines that the host vehicle speed V100 is slower than the regulation speed Vreg applied to the host vehicle 100 at that time by at least a predetermined speed (first speed V1), the lane changing device 10 adds the numerical value as the following vehicle catch-up possibility level LVrsk.

The lane changing device 10 recognizes the speed regulation Vreg applied to the vehicle 100 based on information related to road signs included in the surrounding detection information IS (particularly, camera image information). Alternatively, the lane changing device 10 can identify the current position P100 of the vehicle 100 from the GPS signal, compare the identified current position P100 of the vehicle 100 with the map information stored in the map information database 72, identify the road on which the vehicle 100 is traveling at that time, read the speed regulation Vreg set for that road from the map information database 72, and recognize the speed regulation Vreg applied to the vehicle 100. The lane changing device 10 can also receive a radio signal indicating the speed regulation Vreg transmitted from a transmitter (so-called roadside device) installed at the side of the road on which the vehicle 100 is traveling at that time using the receiving device 71, and recognize the speed regulation Vreg applied to the vehicle 100 based on the radio signal.

In addition, if a traffic jam occurs ahead of the vehicle 100 and the vehicle 100 is approaching the location where the traffic jam occurs, it is assumed that the vehicle 100 will approach the location where the traffic jam occurs after starting the lane change driving process and will have to decelerate. In that case, the vehicle 100 may be caught up with the following vehicle 200R before the vehicle 100 completes the lane change. In this case, if a traffic jam occurs ahead of the vehicle 100 and the distance D between the vehicle 100 and the location where the traffic jam occurs is less than a predetermined distance (traffic jam reach distance Dth), the lane change device 10 determines that the following vehicle 200R may catch up with the vehicle 100 before the vehicle 100 completes the lane change after starting the lane change driving process. In other words, the lane change device 10 determines that the following vehicle 200R may be detected and the cancellation condition Ccan may be established before the vehicle 100 completes the lane change after starting the lane change driving process.

In this example, when the distance D between the vehicle 100 and the congestion occurrence location is equal to or less than the congestion reach distance Dth, the possibility that the following vehicle 200R will catch up with the vehicle 100 before the vehicle 100 completes changing lanes is quantified in advance. Then, when the lane changing device 10 determines that the distance D between the vehicle 100 and the congestion occurrence location is equal to or less than the congestion reach distance Dth, the lane changing device 10 adds the numerical value as the following vehicle catch-up possibility level LVrsk.

The lane changing device 10 receives a radio signal indicating information related to the location of the traffic jam by the receiving device 71, identifies the location of the traffic jam based on the radio signal, and identifies the current position P100 of the vehicle 100 based on the GPS signal. It then obtains the distance D between the vehicle 100 and the location of the traffic jam from the identified location of the traffic jam and the current position P100 of the vehicle 100.

6, when the vehicle speed V100 is faster than the vehicle speed V200 of the vehicle in front 200F by a certain speed or more, it is assumed that the vehicle 100 must be decelerated after the lane change travel processing is started. In that case, the vehicle 100 may be caught up with the vehicle 200R behind before the lane change of the vehicle 100 is completed. Therefore, when the vehicle 200F in front is present and the vehicle speed V100 is faster than the vehicle speed V200 of the vehicle in front 200F by a certain speed (second speed V2) or more, the lane change device 10 determines that the vehicle 200R behind may catch up with the vehicle 100 before the lane change of the vehicle 100 is completed after the lane change travel processing is started. In other words, the lane changing device 10 determines that there is a possibility that after the start of the lane change driving process, the following vehicle 200R will be detected and the cancellation condition Ccan will be satisfied before the host vehicle 100 completes the lane change.

In this example, when the host vehicle speed V100 is faster than the vehicle speed V200 of the leading vehicle 200F by at least the second speed V2, the possibility that the trailing vehicle 200R will catch up with the host vehicle 100 before the host vehicle 100 completes its lane change is quantified in advance. Then, when the lane changing device 10 determines that the host vehicle speed V100 is faster than the vehicle speed V200 of the leading vehicle 200F by at least the second speed V2, it adds the numerical value as the trailing vehicle catch-up possibility level LVrsk.

The lane changing device 10 detects the vehicle ahead 200F based on the surrounding detection information IS and obtains the vehicle speed V200 of the detected vehicle ahead 200F.

In addition, the traveling speed of a vehicle traveling in the overtaking lane is generally faster than the traveling speed of a vehicle traveling in the driving lane. Therefore, as shown in FIG. 7, when the host vehicle 100 is traveling in the driving lane (i.e., the first lane LN1) and the target lane LN_T is the overtaking lane (i.e., the second lane LN2), the host vehicle 100 may be caught up by the following vehicle 200R before the host vehicle 100 completes the lane change after the lane change traveling process is started. Therefore, the lane change device 10 determines that the following vehicle 200R may catch up with the host vehicle 100 before the host vehicle 100 completes the lane change after the lane change traveling process is started when the host vehicle 100 is traveling in the driving lane and the target lane LN_T is the overtaking lane. In other words, the lane changing device 10 determines that there is a possibility that after the start of the lane change driving process, the following vehicle 200R will be detected and the cancellation condition Ccan will be satisfied before the host vehicle 100 completes the lane change.

In this example, when the host vehicle 100 is traveling in the driving lane and the target lane LN_T is an overtaking lane, the possibility that the following vehicle 200R will catch up with the host vehicle 100 before the host vehicle 100 completes a lane change is quantified in advance. Then, when the lane change device 10 determines that the host vehicle 100 is traveling in the driving lane and the target lane LN_T is an overtaking lane, it adds the numerical value as the following vehicle catch-up possibility level LVrsk.

The lane change device 10 identifies the current position P100 of the vehicle 100 based on the GPS signal, compares the identified current position P100 of the vehicle 100 with the map information stored in the map information database 72, identifies the road on which the vehicle 100 is currently traveling, reads the type of each lane on that road from the map information database 72, and determines whether the vehicle lane LN_O is a driving lane and whether the target lane LN_T is an overtaking lane.

In addition, if the detection accuracy of the surrounding information detection device 60 is maintained at a sufficient level, the following vehicle 200R that would be detected by the surrounding information detection device 60 may not be detected by the surrounding information detection device 60 if the detection accuracy of the surrounding information detection device 60 is insufficient. In this case, if the lane change driving process is started just because it is determined that the following vehicle 200R does not exist, the host vehicle 100 may be caught up with the following vehicle 200R before the host vehicle 100 completes the lane change. Therefore, the lane change device 10 performs a self-diagnosis of the detection accuracy of the surrounding information detection device 60, and if the detection accuracy obtained thereby is equal to or lower than a predetermined accuracy, it determines that there is a possibility that the following vehicle 200R will catch up with the host vehicle 100 before the host vehicle 100 completes the lane change after the start of the lane change driving process. In other words, the lane changing device 10 determines that there is a possibility that after the start of the lane change driving process, the following vehicle 200R will be detected and the cancellation condition Ccan will be satisfied before the host vehicle 100 completes the lane change.

In this example, if the detection accuracy of the surrounding information detection device 60 is equal to or lower than a predetermined accuracy, the possibility that the following vehicle 200R will catch up with the host vehicle 100 before the host vehicle 100 completes a lane change is quantified in advance. Then, if the lane change device 10 determines that the detection accuracy of the surrounding information detection device 60 is equal to or lower than the predetermined accuracy, it adds the numerical value as the following vehicle catch-up possibility level LVrsk.

When the lane change device 10 calculates the following vehicle catch-up probability level LVrsk as described above, the higher the following vehicle catch-up probability level LVrsk is, the shorter the target lane change time TLCtgt is set to a time that is shorter than the reference time TLCbase.

When the lane change device 10 sets the target lane change time TLCtgt, it sets the route along which the vehicle 100 will travel in order to complete the lane change within the target lane change time TLCtgt as the target lane change route Rtgt.

When the lane change device 10 sets the target lane change route Rtgt, it starts a lane change driving process that controls the operation of the driving device 20 so that the vehicle 100 travels along the target lane change route Rtgt.

When the lane change of the vehicle 100 is completed, the lane change device 10 ends the lane change driving process, thereby ending the lane change control. As described above, in this example, when the lane change control is ended, the lane keeping control is started.

When the lane-changing device 10 detects a following vehicle 200R approaching the vehicle 100 during lane-changing driving processing, and determines that it is preferable to cancel the lane-changing driving processing (i.e., when the cancellation condition Ccan is satisfied), the lane-changing device 10 cancels the lane-changing driving processing.

The above-mentioned lane change device 10 sets the target lane change time TLCtgt to a shorter time as the following vehicle catch-up probability level LVrsk is higher, but may be configured to set the target lane change time TLCtgt depending on whether the following vehicle catch-up probability level LVrsk is equal to or higher than a predetermined level LVth.

In other words, when the lane change device 10 calculates the following vehicle catch-up probability level LVrsk, it determines whether the following vehicle catch-up probability level LVrsk is equal to or greater than a predetermined level LVth.

When the following vehicle overtaking probability level LVrsk is equal to or higher than a predetermined level LVth, the lane change device 10 sets a predetermined time TLCshort that is shorter than the reference time TLCbase as the target lane change time TLCtgt.

On the other hand, when the following vehicle overtaking probability level LVrsk is smaller than the predetermined level LVth, the lane change device 10 sets the reference time TLCbase as the target lane change time TLCtgt.

The above is an overview of the operation of the lane change device 10. According to this, the higher the following vehicle overtaking probability level LVrsk is, the shorter the time TLCrsk or TLCshort is set as the target lane change time TLCtgt, and the host vehicle 100 changes lanes to an adjacent lane by lane change control so that the lane change is completed within the target lane change time TLCtgt. Therefore, even if there is a following vehicle 200R approaching the host vehicle 100 at high speed, the host vehicle 100 can reliably complete the lane change.

<Specific operation of lane change device>
Next, there will be described a specific operation of the lane-changing device 10. The CPU of the ECU 90 of the lane-changing device 10 executes a routine shown in Fig. 8 at a predetermined calculation cycle.

Therefore, at a predetermined timing, the CPU starts processing from step 800 in FIG. 8, proceeds to step 805, and determines whether the value of the lane change condition flag XLC is "1". The lane change condition flag XLC is a flag that indicates whether execution of lane change control is requested, and its value is set to "1" when execution of lane change control is requested, and is set to "0" when execution of lane change control is not requested.

If the CPU judges "Yes" in step 805, the process proceeds to step 810, where it judges whether the value of the lane-changing driving flag XLCexe is "0". The lane-changing driving flag XLCexe is a flag that indicates whether lane-changing driving processing is being executed, and its value is set to "1" when lane-changing driving processing is being executed, and is set to "0" when lane-changing driving processing is not being executed.

If the CPU judges "Yes" at step 810, the process proceeds to step 815, where it judges whether the value of the prohibition condition flag XF is "0". The prohibition condition flag XF is a flag that indicates whether the prohibition condition CF is satisfied, and its value is set to "1" if the prohibition condition CF is satisfied, and is set to "0" if the prohibition condition CF is not satisfied.

If the CPU judges "Yes" in step 815, it proceeds to step 820 and judges whether or not a following vehicle 200R is present (whether or not a following vehicle 200R has been detected).

If the CPU judges "Yes" in step 820, the process proceeds to step 825 and executes the routine shown in FIG. 9. Thus, when the CPU proceeds to step 825, it starts the process from step 900 in FIG. 9, and proceeds to step 905, where it sets the reference time TLCbase as the target lane-change time TLCtgt. Next, the CPU proceeds to step 910 and sets the target lane-change route Rtgt.

The CPU then proceeds to step 915 and sets the value of the lane change driving start flag XLCstart to "1." The lane change driving start flag XLCstart is a flag that indicates whether or not to start lane change driving processing, and its value is set to "1" when lane change driving processing is started, and is set to "0" when lane change driving processing is ended.

Next, the CPU proceeds to step 920 and sets the value of the lane-changing driving flag XLCexe to "1." The CPU then proceeds to step 895 in FIG. 8 via step 995 and temporarily ends this routine.

On the other hand, if the CPU judges "No" in step 820, it advances the process to step 830 and executes the routine shown in FIG. 10 or FIG. 11. Therefore, if the CPU is configured to execute the routine shown in FIG. 10 when it advances the process to step 830, when it advances the process to step 830, it starts the process from step 1000 in FIG. 10, advances the process to step 1005, and calculates the following vehicle catch-up possibility level LVrsk. Next, the CPU advances the process to step 1010, and sets the time TLCrsk obtained according to the following vehicle catch-up possibility level LVrsk as the target lane change time TLCtgt. Next, the CPU advances the process to step 1015, and sets the target lane change route Rtgt.

Then, the CPU proceeds to step 1020 and sets the value of the lane change driving start flag XLCstart to "1". The CPU then proceeds to step 1025 and sets the value of the lane change driving in progress flag XLCexe to "1". After that, the CPU proceeds to step 895 in FIG. 8 via step 1095 and temporarily ends this routine.

On the other hand, if the CPU is configured to execute the routine shown in FIG. 11 when the process proceeds to step 830, the process starts from step 1100 in FIG. 11 when the process proceeds to step 830, and the process proceeds to step 1105 to calculate the following vehicle catching up possibility level LVrsk. Next, the CPU proceeds to step 1111 to determine whether the following vehicle catching up possibility level LVrsk is equal to or greater than a predetermined level LVth.

If the CPU judges "Yes" in step 1111, the process proceeds to step 1112, where the CPU sets the predetermined time TLCshort as the target lane change time TLCtgt. Next, the CPU proceeds to step 1115.

On the other hand, if the CPU determines "No" in step 1111, the process proceeds to step 1113, where the CPU sets the reference time TLCbase as the target lane change time TLCtgt. Next, the CPU proceeds to step 1115.

When the CPU advances the process to step 1115, it sets the target lane change route Rtgt. Next, the CPU advances the process to step 1120, where it sets the value of the lane change driving start flag XLCstart to "1". Next, the CPU advances the process to step 1125, where it sets the value of the lane change driving in progress flag XLCexe to "1". After that, the CPU advances the process to step 895 in FIG. 8 via step 1195, and temporarily ends this routine.

If the CPU judges "No" at step 805, step 810, or step 815 in FIG. 8, it advances the process to step 895 and temporarily ends this routine.

Furthermore, the CPU executes the routine shown in FIG. 12 at a predetermined calculation cycle. Therefore, at a predetermined timing, the CPU starts processing from step 1200 in FIG. 12, advances the processing to step 1205, and determines whether the value of the lane change driving start flag XLCstart is "1".

If the CPU judges "Yes" in step 1205, it proceeds to step 1210 and judges whether the value of the lane change driving cancellation flag XLCcan is "0". The lane change driving cancellation flag XLCcan is a flag that indicates whether the cancellation condition Ccan is satisfied after the start of the lane change driving process, and its value is set to "1" if the cancellation condition Ccan is satisfied after the start of the lane change driving process, and is set to "0" if the cancellation condition Ccan is not satisfied after the start of the lane change driving process.

If the CPU judges "Yes" in step 1210, the process proceeds to step 1215 and executes lane change driving processing. Next, the CPU proceeds to step 1220 and determines whether the lane change has been completed.

If the CPU determines "Yes" in step 1220, the process proceeds to step 1225 and ends the lane change driving process. Next, the CPU proceeds to step 1230 and sets the values of the lane change condition flag XLC, lane change driving start flag XLCstart, lane change driving in progress flag XLCexe, lane change driving stop flag XLCcan, and prohibition condition flag XF to "0". After that, the CPU proceeds to step 1295 and ends this routine.

On the other hand, if the CPU determines "No" at step 1220, it proceeds directly to step 1295 and temporarily ends this routine.

If the CPU determines "No" in step 1210, the process proceeds to step 1235 and stops the lane change driving process. Next, the CPU proceeds to step 1240 and sets the values of the lane change condition flag XLC, lane change driving start flag XLCstart, lane change driving in progress flag XLCexe, lane change driving stop flag XLCcan, and prohibition condition flag XF to "0". After that, the CPU proceeds to step 1295 and temporarily ends this routine.

If the CPU determines "No" in step 1205, it proceeds directly to step 1295 and ends this routine.

The above is the specific operation of the lane change device 10.

The present invention is not limited to the above embodiment, and various modifications can be made within the scope of the present invention.

10... lane change device, 20... driving device, 42... lane change request switch, 51... vehicle speed detection device, 52... GPS device, 60... surrounding information detection device, 61... radio wave sensor, 62... image sensor, 70... road information detection device, 71... receiving device, 72... map information database, 90... ECU, 100... host vehicle, 200R... following vehicle

Claims (5)

A lane change device that executes lane change control to change a vehicle to an adjacent lane,
estimating a possibility that a following vehicle traveling in an adjacent lane that is approaching the host vehicle from behind and that causes the host vehicle to change lanes through the lane change control will catch up with the host vehicle;
a target lane change time, which is a target time from when the host vehicle starts to change lanes by the lane change control to when the host vehicle completes changing lanes to the adjacent lane, is set to a shorter time as the possibility of the host vehicle catching up with the following vehicle increases;
performing a lane change of the host vehicle to the adjacent lane by the lane change control so that the lane change to the adjacent lane is completed within the set target lane change time;
In the lane changing device configured as described above,
The vehicle is equipped with a surrounding information detection device that detects information about the surroundings of the vehicle,
When a first condition is satisfied that the following vehicle does not exist and the detection accuracy of the surrounding information detection device is equal to or lower than a predetermined accuracy, it is determined that the following vehicle is likely to catch up with the host vehicle,
when it is determined that there is a possibility that the following vehicle will catch up with the host vehicle due to the first condition being satisfied, adding a predetermined first numerical value as a following vehicle catch-up possibility level, which is a level indicating the possibility of the following vehicle catching up;
The higher the level of the possibility of overtaking the following vehicle, the shorter the target lane change time is set.
A lane changing device configured as follows. 2. The lane change device according to claim 1,
When a second condition is satisfied that there is no following vehicle and the traveling speed of the host vehicle is slower than a first speed or more than a regulated speed applied to the host vehicle, it is determined that there is a possibility that the following vehicle will catch up with the host vehicle,
when it is determined that there is a possibility that the following vehicle will catch up with the host vehicle due to the second condition being satisfied, a predetermined second numerical value is added as the following vehicle catch-up possibility level.
A lane changing device configured as follows. 2. The lane change device according to claim 1,
When a third condition is satisfied, that is, there is no following vehicle and the distance between the host vehicle and a congestion location ahead of the host vehicle is equal to or shorter than a predetermined distance, it is determined that there is a possibility that the following vehicle will catch up with the host vehicle,
when it is determined that there is a possibility that the following vehicle will catch up with the host vehicle due to the third condition being satisfied, a predetermined third numerical value is added as the following vehicle catch-up possibility level.
A lane changing device configured as follows. 2. The lane change device according to claim 1,
if a fourth condition is satisfied that there is no rear vehicle and the traveling speed of the host vehicle is faster than the traveling speed of the leading vehicle by a second speed or more, it is determined that there is a possibility that the rear vehicle will catch up with the host vehicle;
when it is determined that there is a possibility that the following vehicle will catch up with the host vehicle due to the fourth condition being satisfied, a predetermined fourth numerical value is added as the following vehicle catch-up possibility level.
A lane changing device configured as follows. 2. The lane change device according to claim 1,
When a fifth condition is satisfied, that is, there is no following vehicle, the host vehicle is traveling in a driving lane, and the adjacent lane is an overtaking lane, it is determined that there is a possibility that the following vehicle will catch up with the host vehicle,
when it is determined that there is a possibility that the following vehicle will catch up with the host vehicle due to the fifth condition being satisfied, a predetermined fifth numerical value is added as the following vehicle catch-up possibility level.
A lane changing device configured as follows.

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