JP2018158684A - Travel control device for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce influence on vehicle behavior and traffic flow when cancelling a traffic lane change due to behavior of other vehicle during changing a traffic lane.SOLUTION: A travel control device for a vehicle comprises: a periphery recognizing function that recognizes a line separating an own traffic lane and an adjacent traffic lane and also recognizing other vehicles on each traffic lane; an environmental state estimating section that acquires a state of an own vehicle; a route generating section that generates a target route for changing a traffic lane on the basis of information acquired by the environmental state estimating section; and a vehicle control section that exerts speed control and steering control in order to cause the own vehicle to follow the target route. The travel control device for the vehicle is able to change a traffic lane to an adjacent traffic lane in order to avoid preceding other vehicle. The travel control for the vehicle further comprises: a function of determining whether to continue changing a traffic lane due to the location of the own vehicle with respect to a line 5c separating the adjacent traffic lane, in a case where other vehicle is recognized in a predetermined area defined by a predetermined distance ahead of the own vehicle, a predetermined distance behind the own vehicle, and a predetermined distance at a side of the own vehicle; and a function of reproducing a target route in order to return to the previous traffic lane in a case where it is determined that it is not necessary to continue changing the traffic lane.SELECTED DRAWING: Figure 7

Description

  The present invention relates to a travel control device for a vehicle, and more particularly to a travel control device for a vehicle having an automobile line changing function.

  Various technologies that allow the vehicle to partially perform recognition, judgment, and operation that have been performed by the driver in order to reduce the burden on the driver, such as ACC (Adaptive Cruise Control), LKA (Lane Keeping Assist) Etc. have been put to practical use. Further, a technology has been developed that changes lanes by automatic steering when the speed of the preceding vehicle is lower than the set speed of the host vehicle during follow-up running by ACC.

  For example, Patent Document 1 detects an overtaking target vehicle to be overtaken in front of the traveling lane of the host vehicle based on the surrounding environment information and the traveling information, and follows the rear of the traveling lane of the own vehicle based on the surrounding environment information. It is described that the vehicle is detected as a vehicle following the original lane, the vehicle to be overtaken and the vehicle following the vehicle lane are monitored, and the overtaking traveling for the vehicle to be overtaken is variably controlled based on the monitoring result.

Japanese Patent Laid-Open No. 2006-4443

  By the way, even if it is determined that lane change by autopilot is feasible, it may be better to cancel the lane change due to a sudden change in the traveling state of other vehicles. However, in Patent Document 1, the criterion for canceling the lane change is based on the relative speed of the following vehicle with respect to the own vehicle or the intention to change the lane of the following vehicle, and the own vehicle position is not considered, so the lane change is almost completed. In spite of this, there is a case where the lane change is canceled and the vehicle returns to the original lane by reverse steering, and there is a concern that this may cause a vehicle behavior that affects traffic flow and causes discomfort to the passengers. It was.

  The present invention has been made in view of the above circumstances, and its purpose is to reduce the influence on the vehicle behavior and traffic flow when the lane change is stopped by the behavior of another vehicle during the lane change. The object is to provide a vehicle travel control device.

In order to solve the above problems, the present invention provides:
An environment state estimation unit including a surrounding recognition function for recognizing the lane markings of adjacent lanes and other vehicles on each lane from information of external sensors, and a function of acquiring the state of the vehicle from information of internal sensors;
A route generation unit that generates a target route for a vehicle line change based on information acquired by the environmental state estimation unit;
A vehicle control unit that performs speed control and steering control so that the vehicle follows the target route;
In order to avoid preceding other vehicles, in a vehicle travel control device capable of changing the lane to the adjacent lane,
When another vehicle is recognized within a predetermined area defined by a predetermined distance in front of the vehicle, a predetermined distance in the rear, and a predetermined distance in the side during the change of the vehicle lane, with respect to the dividing line with the adjacent lane A function for determining whether or not to continue the lane change according to the position of the vehicle, and a function for regenerating the target route to return to the original lane when it is determined that the lane change should not be continued. It is characterized by being.

  According to the vehicle travel control device of the present invention, when another vehicle entering the predetermined area is recognized during the lane change, whether or not the lane change can be continued is determined based on the position of the own vehicle. Since the change is continued or cancelled, it is possible to avoid unnatural vehicle behavior such as stopping the lane change and returning to the original lane when the lane change to the adjacent lane is almost completed. It is advantageous in reducing the influence.

It is the schematic which shows the traveling control system of a vehicle. It is a schematic top view which shows the external field sensor group of a vehicle. It is a block diagram which shows the traveling control system of a vehicle. It is a flowchart which shows the traveling control which concerns on this invention embodiment. (A) is a front inter-vehicle distance and side inter-vehicle distance, (b) is a plan view showing a rear inter-vehicle distance. (A) (b) is a top view which shows an example in case the necessity of judging lane change cancellation arises with the behavior of the other vehicle in the lane change. (A) Lane change stop judgment standard based on own vehicle position, (b) is a plan view showing a coordinate system of the vehicle.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
In FIG. 1, a vehicle 1 equipped with a travel control system according to the present invention performs recognition, determination, and operation on the vehicle side in addition to conventional automobile components such as an engine and a vehicle body. In addition, an external sensor 21 for detecting the environment around the vehicle, an internal sensor 22 for detecting vehicle information, a controller / actuator group for speed control and steering control, an ACC controller 14 for constant speed / following control, and And an automatic operation controller 10 for carrying out an automobile line change (route following control).

  A controller / actuator group for speed control and steering control includes an EPS (electric power steering) controller 31 for steering control, an engine controller 32 for acceleration / deceleration control, ESP (registered trademark; stability control system) / ABS. (Anti-lock brake system) A controller 33 is included.

  The outside sensor 21 automatically drives the dividing line 5 on the road that defines the own lane 51 and the adjacent lane 52, the presence and relative distance of other vehicles, obstacles, people, etc. around the own vehicle as image data and point cloud data. It consists of a plurality of detection means for inputting to the controller 10.

  For example, as shown in FIG. 2, the vehicle 1 includes a millimeter wave radar (211) and a camera (212) as the front detection means 211 and 212, and a LIDAR (laser image detection as the front side detection means 213 and the rear side detection means 214. / Ranging), equipped with a camera (back camera) as the rear detection means 215, covering 360 degrees around the own vehicle, the position and distance of vehicles and obstacles, etc. within a predetermined distance in the longitudinal direction of the own vehicle, and the position of the marking line Can be detected.

  The internal sensor 22 is composed of a plurality of detection means for measuring a physical quantity representing the motion state of the vehicle, such as a vehicle speed sensor, a yaw rate sensor, and an acceleration sensor. As shown in FIG. And is processed together with the input from the external sensor 21.

  The automatic operation controller 10 includes an environment / state estimation unit 11, a route generation unit 12, and a vehicle control unit 13, and stores a computer for performing functions as described below, that is, a program and data. A ROM, a CPU that performs arithmetic processing, a RAM that reads the program and data, stores dynamic data and arithmetic processing results, and an input / output interface are configured.

  The environment / state estimation unit 11 acquires the absolute position of the host vehicle using the positioning unit 24 such as GPS, and based on the outside lane data such as image data and point cloud data acquired by the outside sensor 21, The lane marking position, the other vehicle position and the speed of the adjacent lane 52 are estimated. In addition, the movement state of the vehicle is acquired from the internal world data acquired by the internal sensor 22.

  The route generation unit 12 refers to the map information 23, and is detected by the internal sensor 22, the own vehicle position estimated by the environment / state estimation unit 11, the lane line position of the adjacent lane 52, the other vehicle position and the speed. The target route 50 from the own vehicle position to the destination target point in the lane change is generated based on the movement state of the own vehicle.

  The vehicle control unit 13 calculates a target vehicle speed and a target rudder angle based on the target route 50, transmits a vehicle speed command to the ACC controller 14, and transmits a rudder angle command for route following to the EPS controller 31.

  The vehicle speed is also input to the EPS controller 31 and the ACC controller 14. Since the steering torque changes depending on the vehicle speed, the EPS controller 31 transmits a torque command to the steering mechanism 41 with reference to the steering angle-steering torque map for each vehicle speed. The engine controller 32, the ESP / ABS controller 33, and the EPS controller 31 control the engine 42, the brake 43, and the steering mechanism 41, whereby the vertical and horizontal movements of the vehicle 1 are controlled.

(Outline of the car line change function)
Next, an outline of the lane changing function will be described on the assumption of a lane change for overtaking the preceding vehicle on a highway with two or more lanes on one side with a median strip.

  The automatic operation controller 10 (route generation unit 12) obtains external environment information (lane, own vehicle position, own vehicle travel lane, and other vehicle position traveling in the adjacent lane, acquired by the environment / state estimation unit 11 through the external sensor 21. Speed) and the inner world information (vehicle speed, yaw rate, acceleration) acquired by the inner world sensor 22, the lane change target route and the target vehicle speed are generated. Then, based on the generated target route / target vehicle speed and the inter-vehicle distance / relative speed with other vehicles, it is determined whether or not the lane change is possible. If it is determined that the lane change is possible, the “lane change flag” Stand up.

  Only when the lane change function is activated and the “lane change enable flag” is set, and the driver intends to change lanes (such as turn signal operation), the automatic operation controller 10 automatically follows the target route generated. Lane change is executed by steering.

  The automatic operation controller 10 determines the vehicle position and the vehicle's motion characteristics, that is, the front wheel steering angle δ generated when the steering torque T is applied to the steering mechanism 41 while traveling at the vehicle speed V, and the yaw rate and lateral force generated by the vehicle motion. From the relationship of acceleration, the speed, posture, and lateral displacement of the vehicle after Δt seconds are estimated, a steering angle command is given to the EPS controller 31 so that the lateral displacement becomes yt after Δt seconds, and the speed Vt is reached after Δt seconds. To the ACC controller 14.

  When the lane change is completed, the vehicle position is at the center of the adjacent lane (xc ± α, yc ± β; α and β are tolerances), and the inter-vehicle distance from the overtaking vehicle depends on the own vehicle speed and the rear vehicle speed. Judgment is made when it is larger than the predetermined rearward predetermined distance. The predetermined rear distance will be described later.

(Relationship between ACC, EPS, ESP / ABS, engine control and vehicle line change function)
The vehicle line changing function is implemented mainly by combining longitudinal control (speed control) by the ACC controller 14 and lateral control (steering control) by the EPS controller 31. The ACC controller 14, the EPS controller 31, the engine controller 32, and the ESP / ABS controller 33 operate independently regardless of automatic steering. However, during the operation of the vehicle line change function, a command from the automatic operation controller 10 is provided. It can be activated by input.

  Receiving the steering angle command from the automatic operation controller 10, the EPS controller 31 refers to the vehicle speed-steering angle-steering torque map, issues a torque command to the actuator (EPS motor), and the steering mechanism 41 targets the front wheels. Give the rudder angle. The ACC controller 14 that has received the speed command from the automatic operation controller 10 issues a deceleration command for brake control or an acceleration / deceleration command for engine control according to the vehicle speed acquired from the internal sensor 22.

  The ESP / ABS controller 33 that has received the deceleration command from the ACC controller 14 issues a hydraulic pressure command to the actuator and controls the braking force of the brake 43 to control the vehicle speed. Further, the engine controller 32 that receives the acceleration / deceleration command from the ACC controller 14 controls the actuator output (throttle opening), thereby giving a torque command to the engine 42 and controlling the driving force to control the vehicle speed. .

  The ACC function functions by a combination of hardware and software such as the millimeter wave radar 211, the ACC controller 14, the engine controller 32, and the ESP / ABS controller 33 as the external sensor 21.

  In other words, when there is no preceding vehicle, it runs at a constant speed at the target vehicle speed (cruise control set speed), and when it catches up with the preceding vehicle (when the preceding vehicle speed is less than the target vehicle speed), it is set according to the preceding vehicle speed. The vehicle follows the preceding vehicle while maintaining the inter-vehicle distance according to the time gap (inter-vehicle time = inter-vehicle distance / own vehicle speed).

  Note that there is LKA (lane keeping assist) as a function using the steering control by the EPS controller 31. Based on the image data acquired by the external sensor 21 (cameras 212 and 215), the LKA detects the lane line and the vehicle position by the environment / state estimation unit 11 of the automatic operation controller 10 so that it can travel in the center of the lane. In addition, the EPS controller 31 assists the steering force and does not perform automatic steering.

  Therefore, when shifting from the situation in which the LKA function is operating in conjunction with ACC to lane change, the driver's intention to change lane (blinker blinking) with the “lane change enable flag” set. Then, the LKA function is canceled and the vehicle line change is started. After the lane change is completed, the LKA function is activated again and the vehicle returns to ACC running in conjunction with the LKA function.

(Ambient environment change during lane change)
By the way, as already mentioned, the surrounding environment of the vehicle and the target route are confirmed, and only when the driver ’s intention to change lanes (such as turn signal operation) is in the state where the “lane change possible flag” is set, Although the lane change is started, there is a possibility that the surrounding environment may change due to the behavior of other vehicles before the lane change is started and the vehicle moves to the adjacent lane.

  For example, as shown in FIG. 6A, during the lane change from the own lane (left lane) 51 to the adjacent lane (center lane) 52 in order to avoid the other vehicle 2 'trying to enter from the merge lane 54 When the other vehicle 3 traveling on the overtaking lane (right lane) 53 changes to the adjacent lane 52 and enters within a predetermined distance on the right side of the own vehicle 1, or as shown in FIG. In order to pass the preceding other vehicle 2, the preceding other vehicle 2 starts to change the lane to the passing lane 53 while the lane (central lane) 52 changes to the passing lane 53, and the own vehicle 1 ' This is the case when the vehicle enters the predetermined distance on the right front side. The following problems are assumed for such changes in the surrounding environment during lane change.

  Whether the lane change can be continued is based on the existence of other vehicles on the target route of the own vehicle, the distance between other vehicles after returning to the original lane, the relative speed of the following vehicle with respect to the own vehicle, or the lane change of the following vehicle If it is an intention (blinker blinking), the current vehicle position is not considered. For this reason, if the front and rear wheels of the host vehicle are already on the target lane side of the target lane (adjacent lane) and the lane marking of the original lane, that is, the transition to the adjacent lane is almost complete, the lane change is canceled and the original A case of returning to the lane is also assumed, and even if such a vehicle behavior indicates a lane change intention (blinker blinking), the subsequent vehicle appears suspicious.

  Further, in the above case, the time required from the start of lane change to the cancellation to the return to the original lane is about twice as long by simple calculation as compared with the case where the lane change is continued. If the lane change is canceled when the front and rear wheels of the host vehicle are in the original lane, the vehicle can return to the original track with a small steering angle, but the front and rear wheels cross the dividing line and move to the adjacent lane. In a case where the lane change is canceled and the vehicle returns to the original lane in the almost completed state, the change in the lateral acceleration of the vehicle due to reverse steering becomes large, which may cause discomfort to the occupant. Therefore, the lane change continuation determination during the lane change is performed as follows.

(Judgment whether lane change can be continued)
During the lane change, the automatic operation controller 10 (environment / state estimation unit 11) recognizes the lane markings around the vehicle by the external sensor 21, and the lane that was running before the lane change as shown in FIG. 51 division lines 5s and 5c, division lines 5c and 5d of the adjacent lane 52 scheduled to shift after the lane change by route generation, and ground plane center points W _FL , W _FR , W _RL , W of the left and right front and rear wheels of the vehicle Relative position of _RR (relative coordinates of front and rear wheel ground plane center points W _FL , W _FR , W _RL , W _RR with the xy coordinate center of vehicle center of gravity G as the origin) is estimated and constantly monitored.

When an intrusion of another vehicle (lane change or the like) within a “predetermined distance” defined according to the movement state of the own vehicle is detected (the other vehicle recognized by the environment / state estimation unit 11 is “predetermined” The automatic driving controller 10 (route generation unit 12), the right lane 51c of the lane (51) that was traveling before the lane change (original lane 51 side edge), Based on the relative positions of the ground contact surface center points (W _FL , W _FR , W _RL , W _RR ) of the front and rear wheels of the own vehicle, the lane change continuation determination is performed as follows.

(I) Stop the lane change and return to the original lane in the following cases.
(A) The front wheel / rear wheel ground contact surface centers are all located closer to the original lane than the lane marking end.
(B) Only the center of the change-destination-side front wheel ground contact surface is on the change-destination lane side from the lane line end.
(C) Only the change destination side front and rear wheel ground contact surface centers are on the change destination lane side from the lane line end.

(Ii) Continue to change lanes in the following cases.
(D) The center of the ground plane of the change-destination front and rear wheels and the change-source front wheel is located on the change-destination lane side from the lane line end (the ground plane centers of the left and right front wheels and the change-destination rear wheel are changed from the lane line end. It is on the front lane side, that is, only the center of the ground contact surface of the rear wheel on the change source side is on the change lane side from the end of the lane marking line).
(E) The front wheel / rear wheel ground contact surface centers are all on the change destination lane side from the lane line end.

For example, in the vehicle 1b of FIG. 7A, only the right side (change destination side) front wheel ground contact surface center (W _FR ) is on the right side (change destination lane side) from the end of the lane marking 5c, and corresponds to the above (b). To do. Further, in the vehicle 1c of FIG. 7A, only the right side (change destination side) front and rear wheel ground contact surface centers (W _FR , W _RR ) are on the right side (change destination lane side) from the end of the lane marking 5c. corresponding to c). Further, in the vehicle 1d of FIG. 7A, the center of the ground plane (W _FR , W _RR , W _FL ) of the right (change destination side) front and rear wheels and the left (change source side) front wheels is changed from the end of the lane marking line. On the lane side, in other words, the center of the ground plane (W _FL , W _FR , W _RR ) of the left and right front wheels and the right (change destination side) rear wheel is on the change lane side from the lane line end, corresponds to d).

  Since the center of the ground plane of the front wheels on each side of the left and right sides is basically positioned closer to the change destination side than the center of the installation surface of the rear wheels on the same side when the vehicle line is changed, the above (d) is simply left and right front It can also be considered that the center of the ground contact surface of the wheel is on the change destination lane side from the lane line end.

  When the lane change is stopped due to the lane change continuation determination, the route generation unit 12 sets the tracking target to the center line 51c of the lane 51 that was traveling before the lane change, as indicated by an arrow B in FIG. Change and regenerate the target route / vehicle speed. Further, the steering angle command and the speed command are given to the EPS controller 31 and the ACC controller 14 so as to follow the regenerated path.

  However, even if the vehicle position is (d) and (e) above, if another vehicle is approaching the target route 50 or within the minimum predetermined distance, the lane change is stopped and the lane center before the lane change is The route is regenerated with the line as the travel route target at the end of the lane change, and the route following control is performed. The minimum predetermined distance is set separately from the predetermined distance used for determining whether to change lanes. Details will be described later.

(Improved car line change flow)
Hereinafter, the improved automobile line change flow will be described with reference to FIG.

(1) Preparation for starting the lane change function When the driver turns on the lane change function on / off switch (step 100), the operation determination of ACC and LKA is performed (step 101). In this case, ACC / LKA is activated, and the fact that ACC / LKA is being activated is displayed in the meter panel (step 104). When the ACC / LKA is already operating, the automatic operation controller 10, the ACC controller 14, the EPS controller 31, the engine controller 32, the ESP / ABS controller 33, the external sensor 21, and the internal sensor that are necessary for executing the vehicle line change. 22 and a system check of the actuators is performed (step 102).

(2) Judgment of whether or not the automobile line changing function can be activated After the system check, the automatic operation controller 10 determines whether or not the automobile line changing function can be activated (step 103). If for some reason each controller / sensor / actuator does not operate normally and becomes NG, the vehicle line change function cannot be activated in the meter panel and the vehicle is It is notified that the line change function cannot be activated (step 105).

(3) Activation of the vehicle line changing function When the activation determination is OK, the vehicle line changing function is activated (step 110). During activation of the lane change function, the automatic operation controller 10 (environment / state estimation unit 11 and route generation unit 12) describes (i) ambient environment recognition and (ii) lane change route / vehicle speed target described in the next section. Generation is always performed.

(4) Ambient environment recognition and generation of vehicle speed change route vehicle speed target (i) Ambient environment recognition The environment / state estimation unit 11 of the automatic operation controller 10 calculates the self obtained from the point cloud data and image data obtained from the external sensor 21. From the relative coordinates of the vehicle lane marking relative to the vehicle, the relative coordinates and relative speed of other vehicles, and the absolute coordinates of the vehicle acquired by the GPS positioning means 24 with reference to the map information 23, the vehicle position (x , Y coordinate).
(Ii) Generation of Lane Change Route / Vehicle Speed Target In the route generation unit 12 of the automatic operation controller 10, the vehicle position on the lane 51 estimated by the surrounding environment recognition processing of the environment / state estimation unit 11, and the adjacent lane 52 Based on the lane marking position and the vehicle speed acquired by the internal sensor 22, the vehicle position (xt, yt) and the target vehicle speed (Vt) that are assumed to travel in the center of the adjacent lane after Δt seconds are calculated. Based on this, the target route 50 is generated (step 111).

(5) Determination of whether or not the vehicle line can be changed Next, the route generation unit 12 of the automatic operation controller 10 is determined by the generated target route / vehicle speed target, the relative position / speed of the preceding other vehicle detected by the external sensor 21 and the own vehicle speed. There is another vehicle in a “predetermined region” defined by a predetermined distance in the front (X _FOC ), a predetermined distance in the rear (X _ROC ) determined by the own vehicle and the following other vehicle speed, and a predetermined distance in the side (X _SOC ). Whether or not the lane change is possible is determined depending on whether or not.

但し、
Ｘ_LC：車線変更距離（ｍ）、Ｘ_ST：制動後所定距離（ｍ）
Ｖ_VUT：自車両速度（ｋｍ／ｈ）、Ｖ_FD：前方車両速度（ｋｍ／ｈ）
Ｘ_L：車線幅（ｍ）＝３．７５ｍ、ａ_y：自車横加速度（ｍ／ｓ²）、
ＳＴ：所定車間時間（sec）＝１．０sec
最小前方所定距離（Ｘ_FOCｍｉｎ）は、車線幅（Ｘ_L）を現在走行中の車線幅（＝３．７５ｍ）として、自車横加速度ａ_y（ｍ／ｓ²）と自車両速度Ｖ_VUT（ｋｍ／ｈ）に応じて算出した最小値とする。 The concept of the predetermined forward distance (X _FOC ) is shown in FIG. A predetermined distance (X _FOC ) between the host vehicle 1 and the preceding other vehicle 2 can be obtained by the following equation (1).

However,
X _LC : Lane change distance (m), X _ST : Predetermined distance after braking (m)
V _VUT : Own vehicle speed (km / h), V _FD : Front vehicle speed (km / h)
X _L : Lane width (m) = 3.75 m, a _y : Own vehicle lateral acceleration (m / s ² ),
ST: Predetermined inter-vehicle time (sec) = 1.0 sec
The minimum forward predetermined distance (X _FOC min) is determined by assuming that the lane width (X _L ) is the currently traveling lane width (= 3.75 m) and the own vehicle lateral acceleration a _y (m / s ² ) and the own vehicle speed V _VUT The minimum value calculated according to (km / h).

The concept of the rear inter-vehicle distance (X _ROC ) is shown in FIG. The rear (or rear side) predetermined distance (X _ROC ) between the own vehicle 1 and the following other vehicle 4 can be obtained by the following equation 2.
(Formula 2) X _ROC = X _RT + X _BB + X _BD + X _ST
here,
X _RT = (V _RO -V _VUT ) · RT
^{_{X BB = {V RO 2 -}} (V RO - (a RO / 2) · BB) 2} / a RO -V VUT · BB
^{_{X BD = {(V RO 2}} -V VUT 2) / 2 · a RO} - {(V RD -V VUT) / a RO} · V VUT
X _ST = V _VUT · ST
However,
X _RT : rear vehicle reaction distance (m), X _BB : braking rise distance (m)
X _BD : Braking distance (m), X _ST : Predetermined inter-vehicle distance after braking (m)
V _VUT : Own vehicle speed (km / h), V _RO : Rear vehicle speed (km / h)
a _RO : Rear vehicle deceleration (m / s ² ) = 3.0
RT: reaction time (sec) = 1.2 sec
BB: Brake rise time (sec) = 0.5 sec
ST: Predetermined inter-vehicle time (sec) = 1.0 sec
Minimum rear predetermined distance (X _ROC min) is, a _RO: rear vehicle deceleration (m / s ²⁾ the maximum value, for example, a calculated value as a 0.6G (5.88m / s ^2).

A method for calculating the predetermined lateral distance is shown in FIG. The predetermined lateral distance (X _SOC ) between the own vehicle 1 and the other side vehicle 3 can be obtained by the following equation 3. The lane width is the maximum lane width (3.75m) of the Japanese expressway.
(Formula 3) X _SOLC = X _SORC = 1.5X _L
However,
X _SOLC : left side predetermined distance (m)
X _SORC : right side predetermined distance (m)
X _L : Lane width (m) = 3.75 m
The minimum lateral predetermined distance (X _SOC min) is a value calculated as X _L : lane width (m) as the currently traveling lane width (measurable by the external sensor 21), or the coefficient 1.5 is set to 1. Value.

  Change the lane according to the target route generated as described above, overtake the preceding other vehicle, and enter the predetermined area until the rear inter-vehicle distance is equal to or greater than the predetermined distance behind the vehicle (within the predetermined forward distance or the predetermined backward distance) The presence / absence of another vehicle estimated to be in the vicinity is determined (step 112). If it is estimated that there is no other vehicle, it is determined that the lane can be changed, and an “automobile lane changeable flag” is set (step 113).

  The calculation process leading to the above determination is continued while the automobile line changing function is activated, and the automobile line changing flag is updated as needed according to the surrounding environment. On the other hand, if the lane change permission / failure determination is NG, “No lane change” is displayed in the meter panel or the like, and the driver is notified by voice or the like that the lane change is not possible ( Step 114).

(6) Auto lane change ready (READY) display When the flow from the start of the auto lane change function to the lane change enable / disable determination is completed as described above, it is assumed in the meter panel that the auto lane change preparation is ready. “Automobile line change preparation complete (READY)” is displayed (step 120). The driver confirms that the vehicle line can be changed by displaying “Ready to change vehicle line (READY)” during the follow-up running. In addition, when driving in the central lane of a road with three or more lanes on one side, it can be provided corresponding to each of the left and right to indicate whether the vehicle can be changed to either the left or right adjacent lane.

(7) Driver's intention to change car line (winker operation)
In the state where “preparation for vehicle line change preparation (READY)” is displayed as described above, the driver performs turn signal operation to start the vehicle line change (step 130). This blinker operation is a trigger operation for starting the vehicle line change. At the same time, as described above, if the “ready for vehicle line change ready (READY)” display is provided corresponding to each of the left and right sides, Willingness to change to lane.

  After the blinker operation, it is determined whether blinker blinking is possible without immediately blinking blinker (step 131). Whether the blinker blinks is detected by detecting that “the vehicle lane change READY state” and “the driver has made a lane change intention (winker operation)”, and blinking the blinker when both are detected (step 131). (Step 132).

(8) Execution of vehicle line change Automatic steering is started from the point of time when 3 seconds have elapsed after the blinker blinking is started (step 140). At the same time, “change in vehicle line” is displayed in the meter panel, and the driver is notified that the vehicle line is being changed by voice or the like (step 141). With the start of automatic steering, the vehicle is accelerated by an acceleration / deceleration command from the ACC controller 14, travels at the ACC target vehicle speed (cruise control set speed) in the changed lane, and overtakes the preceding other vehicle.

(9) Lane Change Continuity Determination Whether or not the lane change can be continued (detection of intrusion of another vehicle into the predetermined area) is performed by the route generation unit 12 as a lane change continuation determination even during the lane change (step 142). If it is determined that there is no other vehicle intrusion into the predetermined area and the lane change can be continued, a lane change end determination is performed (step 143).

  On the other hand, when the intrusion into the predetermined distance on the front and rear sides due to the lane change of the other vehicle is detected during the lane change, and the lane change continuation determination is NG, the route generation unit 12 Based on the current position (relative position between the wheel ground contact surface center and the lane marking), it is determined whether to cancel the lane change and return to the original lane, or continue the lane change to the target lane. (Step 144).

  At this time, if it is determined that the vehicle is located on the change destination lane side with respect to the original lane side, that is, as described above, (d) the center of the ground contact surface between the change destination front and rear wheels and the change source side front wheel is It is on the change lane side from the lane line end (the center of the ground plane of the left and right front wheels and the change destination side rear wheel is on the change destination lane side from the lane line end, that is, only the center of the contact plane of the change source side rear wheel Lane change continues if it is determined that the center of the front and rear wheel ground planes is on the change lane side from the lane line end. Is done.

  On the other hand, if it is determined that the host vehicle is located closer to the original lane than the change-destination lane, that is, (a) the front wheel / rear wheel ground surface centers are all located closer to the original lane than the lane line end. (B) Only the change front side ground contact surface center is on the change destination lane side from the lane line end, or (c) Only the change front and rear wheel contact surface center is on the change lane side from the lane line end When it is determined that there is, the lane change is stopped, the blinker blinking is stopped, and the route generation unit 12 performs the reverse route and the vehicle speed to follow the lane center line before the lane change by reverse steering. The goal is regenerated (step 160).

  Next, the blinker in the return direction is automatically blinked (step 161), and the return to the original lane is started according to the regenerated target route and vehicle speed (step 162). The determination as to whether or not the return to the original lane has ended is made in the same way as the determination to end the lane change (step 143) described later (step 163).

(10) Automobile line change end determination Automobile line change end determination is made based on the vehicle position (lateral position) and the rear inter-vehicle distance (vertical position), and the vehicle position is at the approximate center of the targeted lane. In addition, the distance between the other vehicle that has passed the vehicle or the distance between the other vehicle and the rear other vehicle when returning to the original lane is larger than the predetermined distance behind the vehicle (step 143). If it is determined that the vehicle line change is completed, the “change in vehicle line” display in the meter panel is turned off (step 145).

(11) Stop of the lane change function After the lane change is completed, if the driver does not turn on the lane change function ON / OFF SW, the lane change function is in the activated state and the surrounding environment is recognized. The generation of the lane change route / vehicle speed target and the determination of whether or not the lane can be changed are continuously performed. However, when the driver changes the lane change function ON / OFF SW (step 146), the vehicle Line change preparation complete (READY) display is turned off (step 147), the lane change function is stopped (step 150), ambient environment recognition, lane change route / vehicle speed target generation, and lane change availability determination are stopped. (Step 151).

(Action and effect)
As described above in detail, in the vehicle travel control apparatus according to the present invention, the vehicle is changed within a predetermined area defined by a predetermined distance in front of the vehicle, a predetermined distance in the rear, and a predetermined distance in the side while the vehicle line is being changed. When a vehicle is recognized, it is determined whether or not the lane change can be continued based on the vehicle position relative to the adjacent lane and the lane change is continued or canceled, so the lane change to the adjacent lane is almost completed. It is possible to avoid unnatural vehicle behavior, such as when stopping the lane change and returning to the original lane, which is advantageous in reducing the influence on traffic flow and occupants, and the lane change time (running across the lane) This is also advantageous in minimizing the amount of time required.

Further, in a preferred aspect of the present invention, the lane change continuation determination unit determines that the center position (W _FL , W _FR ) of the ground contact surface of the left and right front wheels of the host vehicle is adjacent to the lane marking with the adjacent lane. When it is located on the lane side, it is configured to determine that the lane change should be continued, which is advantageous in determining whether to continue the lane change appropriately according to the driving characteristics such as the steering stability of the vehicle. It is.

  The lane change continuation determination unit is configured to determine that the lane change should be continued when the gravity center position (G) of the own vehicle is located on the adjacent lane side with respect to the lane marking with the adjacent lane. May be.

  In the present invention, the lane change continuation determination may be smaller than the predetermined distance in the front, the predetermined distance in the rear, and the predetermined distance in the side when it is determined that the lane change should be continued, The other vehicle in the second predetermined area defined by the second predetermined distance in front, the predetermined distance in the rear, and the predetermined distance in the side that is equal to or greater than the minimum predetermined distance in the front, the minimum predetermined distance in the rear, and the minimum predetermined distance in the lateral direction. When the vehicle is recognized, the target route is regenerated to return to the original lane, so avoid excessive approaching with other vehicles due to continued lane changes. It can be advantageous.

  Although several embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications and changes can be made based on the technical idea of the present invention. I will add.

1 Vehicle (own vehicle)
2 vehicles (preceding other vehicles)
3 vehicles (side cars)
4,4 'vehicle (following other vehicle)
5, 5c, 5d, 5s Dividing line 10 Automatic operation controller 11 Environment / state estimation unit 12 Route generation unit 13 Vehicle control unit 14 ACC controller 21 External sensor 22 Internal sensor 31 EPS controller 32 Engine controller 33 ESP / ABS controller 41 Steering Mechanism 42 Engine 43 Brake 50 Target route 51, 52, 53 Lane

Claims (4)

An environment state estimation unit including a surrounding recognition function for recognizing the lane markings of adjacent lanes and other vehicles on each lane from information of external sensors, and a function of acquiring the state of the vehicle from information of internal sensors;
A route generation unit that generates a target route for a vehicle line change based on information acquired by the environmental state estimation unit;
A vehicle control unit that performs speed control and steering control so that the vehicle follows the target route;
In order to avoid preceding other vehicles, in a vehicle travel control device capable of changing the lane to the adjacent lane,
When another vehicle is recognized within a predetermined area defined by a predetermined distance in front of the vehicle, a predetermined distance in the rear, and a predetermined distance in the side during the change of the vehicle lane, with respect to the dividing line with the adjacent lane A function for determining whether or not to continue the lane change according to the position of the vehicle, and a function for regenerating the target route to return to the original lane when it is determined that the lane change should not be continued. A travel control device for a vehicle.   The lane change continuation determination unit determines that the lane change should be continued when the center position of the ground contact surface of the left and right front wheels of the host vehicle is located on the adjacent lane side with respect to the lane marking with the adjacent lane. The travel control apparatus for a vehicle according to claim 1.   The lane change continuation determination unit is configured to determine that the lane change should be continued when the center of gravity of the vehicle is located on the adjacent lane side with respect to the lane marking with the adjacent lane. The vehicle travel control apparatus according to claim 1.   When it is determined that lane change should be continued, the lane change continuation enable / disable determining means is smaller than the predetermined distance in the front, the predetermined distance in the rear, and the predetermined distance in the side, respectively, and the minimum predetermined distance in front of the own vehicle, When another vehicle is recognized in the second predetermined area defined by the second predetermined distance in front, the predetermined distance in the rear, and the predetermined distance in the side that is equal to or greater than the minimum predetermined distance in the rear and the minimum predetermined distance in the side. The vehicle travel control device according to claim 1, wherein the target route is regenerated to return to the original lane.

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