JP2015202758A - Drive support apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a drive support apparatus capable of appropriately setting a target position for changing lanes from the start to end of a lane change.SOLUTION: A drive support apparatus 1, for use in steering control for changing lanes from a lane where a vehicle has been traveling to an adjacent lane, includes: a division line detection part 13 for detecting division lines on left-right sides of a lane; a target position setup part 34 for setting a target position so as to cause the vehicle to change lanes by using the division lines detected by the division line detection part 13; and a steering control part 36 for controlling steering of the vehicle so as to lead the vehicle to head for the target position. Further, in the case of changing lanes, detection by the division line detection part 13 is switched to detection of only one division line on a side to which the lane is changed, of the division lines on the left-right sides of the travelling lane, so that the target position setup part 34 sets the target position using the position of one division line detected by the division line detection part 13.

Description

  The present invention relates to a driving support apparatus that performs steering control for changing a lane from a lane in which a vehicle is traveling to an adjacent lane.

  When changing the lane, a target position for changing the lane from the lane in which the vehicle was traveling to an adjacent lane is set, and steering control is performed so that the position of the vehicle is directed toward the target position. When setting the target position, usually, the left and right lane markings constituting the lane are detected using a camera, a laser radar, or the like, and the target position is set from the positions of the left and right lane markings. For example, in Patent Document 1, a lane mark (lane marking) of a lane is extracted from a front image captured by a camera, a target line is set from the lane mark, and the vehicle width direction between the target line and the vehicle travel line is set. The lane deviation amount is calculated, and when the lane change is made, the gain is increased as the lane deviation amount is increased, and the control gain is changed from the normal travel control gain to the lane change control gain that suppresses the gain increase in the lane change direction. A lane tracking device that performs automatic steering by a steering actuator using a control gain is disclosed.

Japanese Patent Laying-Open No. 2005-162014

  When setting the target position for lane change, the positions of the left and right lane lines of the traveling lane in which the vehicle was traveling and the positions of the left and right lane lines of the lane to be lane changed are required. However, in the detection of lane markings using a camera, the viewing angle is limited in order to increase the resolution in front of the vehicle, so the right and left lane markings (total of three lane markings) for two lanes are highly accurate. Cannot be detected. Therefore, when the lane is changed, it is necessary to change the lane line to be detected from the left and right lane lines of the travel lane to the left and right lane lines of the lane change target lane. The change of the lane line to be detected is performed at a timing when the vehicle crosses the lane line on the lane change side among the left and right lane lines of the traveling lane. However, in the detection of lane markings using a camera due to the high vehicle speed or the approach angle to the lane change target lane, the left and right lane lines of the lane change target lane may be lost or You may mix up the lane markings. In this case, the target position for lane change cannot be set appropriately. Even in the technique disclosed in Patent Document 1, such a problem occurs because a target line is set by extracting a lane mark using a camera. Note that the same problem may occur when other detection means such as a radar is used.

  Therefore, in this technical field, there is a demand for a driving support device that can appropriately set a target position for changing lanes from the start to the end of lane change.

  A driving assistance apparatus according to an aspect of the present invention is a driving assistance apparatus that performs steering control for changing a lane from a lane in which a vehicle is traveling to an adjacent lane, and detects a left and right lane line of the lane. A line detection unit, a target position setting unit for setting a target position for changing the lane of the vehicle using the lane line detected by the lane line detection unit, and a vehicle heading toward the target position set by the target position setting unit A steering control unit that performs steering control of the vehicle, and when changing lanes, one lane line on the lane change side of the lane lines on the left and right of the lane that has been detected by the lane line detection unit The target position setting unit sets the target position using the position of one lane line detected by the lane line detection unit.

  In this driving support device, a lane line detector detects left and right lane lines of a lane. The lane is composed of a pair of left and right lane markings. The lane marking includes a lane boundary line between the lanes and a lane boundary line between the lane and the shoulder. The lane line detection unit normally can detect the left and right lane lines because the lane to be detected does not change, but cannot detect the left and right (two) lane lines of the lane because the lane to be detected changes when the lane changes There is a case. Therefore, in the driving support device, when the lane change is performed, one lane line on the lane change side of the lane lines on the left and right of the lane that has been detected by the lane line detection unit (the vehicle during the lane change) Switch to detection of only the lane markings. Since only one lane line, which is a common lane line between the lane that is being traveled and the lane to be lane-changed, is detected, the lane line detection unit loses sight of that one lane line or other lane line. It is possible to suppress things that are mistaken for lines. In the driving support device, the target position is set by the target position setting unit using the detected position of one lane line (the end of the lane in which the vehicle is traveling and the end of the lane to be changed). Then, the steering control unit performs steering control of the vehicle so that the target position is reached. In this way, in the driving assistance device, by detecting only one lane line on the side where the lane is to be changed among the left and right lane lines of the traveling lane, the one lane line is used. Thus, the target position for changing the lane from the start to the end of the lane change can be set appropriately. As a result, the lane change can be continued.

  In one mode of the driving support device, the target position setting unit sets the target position using one lane line and the lane width of the lane. In the lane, the other lane marking is located at a position separated from the lane width of one of the left and right lane markings. Therefore, since the position of the other lane line can be estimated from the position of one lane line (the end of the lane) and the lane width, the target position for changing the lane by using the lane width for one lane line Can be set. Thus, in the driving assistance device, an appropriate target position can be easily set by using one lane line and the lane width of the lane.

  In one mode of the driving support device, the target position setting unit acquires a first distance between the predicted position of the vehicle at the start of the lane change and the position of one lane line detected by the lane line detection unit. The second distance obtained by adding the first distance and the half of the lane width is acquired, and the position of the first lane line detected by the lane line detection unit during the lane change, the first distance, and the second distance are used. Set the target position.

  The target position setting unit of the driving support apparatus acquires a first distance between the predicted position of the vehicle at the start of lane change and the position of one lane line detected by the lane line detection unit. This first distance is the distance in the left-right direction from the vehicle at the start of lane change to the lane marking on the lane change side. Further, the target position setting unit obtains a second distance obtained by adding a half of the lane width to the first distance. The second distance is the distance in the left-right direction from the vehicle to the final target position at the start of lane change, and is the distance in the left-right direction that the vehicle moves from the start to the end of lane change. The target position setting unit sets the target position using the position of one lane line detected during the lane change, the first distance, and the second distance. In this way, the driving support device determines the position of one lane line that changes during lane change, the first distance from the vehicle to one lane line that is acquired at the start of lane change, and the final destination from the vehicle. By using the second distance up to, an appropriate target position can be set.

  In one mode of the driving support device, the target position setting unit sets the target position using one lane marking and the vehicle width of the vehicle. The lane width of the lane is set based on the vehicle width of the vehicle and is wider than the vehicle width. Therefore, the target position for changing the lane can be set even if the vehicle width is used for one of the lane markings. Thus, in the driving assistance device, an appropriate target position can be easily set by using one lane marking and the vehicle width.

  According to the present invention, by detecting only one lane line on the lane change side of the lane lines on the left and right of the lane in which the vehicle is traveling, the lane change is performed using the one lane line. The target position for changing the lane from the start to the end can be set appropriately.

It is a schematic block diagram of the driving assistance device which concerns on this Embodiment. It is an example of the time change of the detection position of a lane line when the left and right lane lines are normally detected during lane change. It is an example of the time change of the detection position of the lane line when the left and right lane lines are not normally detected during the lane change, and (a) is a case where the lane line is lost and a constant detection position is output. , (B) is a case where the lane marking is lost and an abnormal detection position is output. It is an example of the time change of the detection position of a lane line in case only one lane line by the side of a lane change is detected during the lane change in the lane line detection part of FIG. It is explanatory drawing of the setting method in the target position setting part of FIG. 1, (a) is a lane change start time, (b) is changing lanes. It is a flowchart which shows the flow of operation | movement of the driving assistance apparatus of FIG.

  Embodiments of a driving assistance apparatus according to the present invention will be described below with reference to the drawings. In addition, the same code | symbol is attached | subjected about the element which is the same or it corresponds in each figure, and the overlapping description is abbreviate | omitted.

  In the present embodiment, the driving support device according to the present invention is applied to a driving support device that is mounted on a vehicle and includes a lane change support function. The driving support device according to the present embodiment detects (recognizes) a lane marking on the lane, sets a target position for changing the lane of the vehicle using the detected lane marking, and sets the vehicle position to the target position. Steering control is performed so as to head. A lane line is a line having a predetermined width such as a white line for dividing a lane, a lane line between the lane and the lane is a lane boundary line, and a lane line between the shoulder and the lane is the outside of the roadway Is a line. In the present embodiment, the lane in which the vehicle was traveling before the lane change is referred to as “travel lane”, the lane adjacent to the travel lane, and the vehicle on which the vehicle travels after the lane change is referred to as “lane change target lane”. .

  Note that the driving support apparatus according to the present embodiment is automatically operated on the vehicle side. For example, when it is determined on the vehicle side whether the driver is unable to perform normal driving operations such as a driver's sleep, sudden illness, loss of consciousness, etc. The driving support device (automatic driving device) is activated. When this driving support device is activated, first, lane maintenance assistance is performed, and a place where the vehicle can be safely stopped by changing the lane safely during lane maintenance driving (for example, a shoulder) is detected. Then, lane change support for moving the vehicle to the location is performed, and finally, automatic stop support for stopping at the location is performed. In this embodiment, the lane change support at this time will be described in detail.

  With reference to FIGS. 1-6, the driving assistance apparatus 1 which concerns on this Embodiment is demonstrated. FIG. 1 is a schematic configuration diagram of a driving support apparatus 1 according to the present embodiment. FIG. 2 is an example of the time change of the detection position of the lane marking when the left and right lane markings are normally detected during the lane change. FIG. 3 is an example of a time change of the detection position of the lane marking when the left and right lane markings are not normally detected during the lane change. FIG. 4 is an example of a time change in the detection position of the lane line when only one lane line on the lane change side is detected during the lane change by the lane line detection unit of FIG. FIG. 5 is an explanatory diagram of a setting method in the target position setting unit of FIG.

  When the lane change is made, the driving support device 1 switches to detection of only one lane line on the lane change side of the left and right lane lines of the traveling lane in the lane line detection, and the position of the one lane line And a target position for changing the lane of the vehicle using the lane width of the traveling lane. Note that the driving support device 1 performs lane keeping support before the lane change, obtains the lane width during the lane keeping support, and stores the lane width.

  For this purpose, the driving support device 1 includes a steering angle sensor 10, a vehicle speed sensor 11, a yaw rate sensor 12, a lane marking detection unit 13, a periphery monitoring unit 14, a steering actuator 20, an ECU [Electronic Control Unit] 30 (a lane width calculation unit 31). A lane width storage unit 32, a detection lane line switching unit 33, a target position setting unit 34, an estimated position calculation unit 35, and a steering control unit 36). In the present embodiment, the lane line detection unit 13 corresponds to the lane line detection unit described in the claims, the target position setting unit 34 corresponds to the target position setting unit described in the claims, and the steering control is performed. The unit 36 and the steering actuator 20 correspond to a steering control unit described in the claims.

  Each position used in the driving support device 1 is handled as a position in a coordinate system relative to the reference position (origin). For example, with the center position in the left-right direction and the center in the front-rear direction of the vehicle as the reference position, in the left-right direction (width direction) of the vehicle, the left side is set to a negative value, the right side is set to a positive value, The front side is a positive value and the rear side is a negative value. Further, with respect to the position of the lane marking and the target position, a gazing point is set ahead of the reference position by a certain distance in the traveling direction of the vehicle, and is handled at a position in the left-right direction relative to the gazing point.

  Before specifically describing the components of the driving support device 1, a case where the left and right lane markings of the lane change target lane cannot be normally detected when the lane is changed will be described with reference to FIGS. FIG. 2 and FIG. 3 show the time change of each lane line detected when the vehicle V changes lanes from the travel lane ML to the lane change target lane CL adjacent to the left side, and the horizontal axis indicates time (seconds). The vertical axis is the position (m) in the left-right direction of the lane marking, and the vehicle V that is running is schematically shown below the vertical axis. In this example, the right lane line L1 and the left lane line L2 of the travel lane ML are detected from the start timing S of the lane change to the timing C when the vehicle V crosses the lane line L2 on the lane change side, and the crossover timing C From lane change end timing E to lane change target lane CL, the right lane line L2 and the left lane line L3 are to be detected. Thus, when changing the lane, it is necessary to change the lane to be detected and change the left and right lane lines to be detected at the timing C when the vehicle V crosses over the lane change L2 on the lane change side. In particular, the lane line L2 straddling the vehicle V is a lane line on the left side of the travel lane ML until the straddle timing C, and is a lane line on the right side of the lane change target lane CL after the straddle timing C.

In FIG. 2, the time change L1 _SC (t) of the position of the right lane line of the travel lane ML and the time change L2 _SC of the position of the left lane line detected from the start timing S of the lane change to the straddle timing C are shown. (T) is shown, and the time change L2 _CE (t) of the position of the right lane line of the lane change target lane CL detected from the straddle timing C to the lane change end timing E and the position of the left lane line The time change L3 _CE (t) is shown. In the case of this example, the right lane line L2 and the left lane line L3 of the lane change target lane CL are normally detected even after the left and right lane lines to be detected are changed at the straddling timing C.

FIG. 3 (a) shows the time change L1 _SC (t) ′ of the position of the right lane line of the travel lane ML detected from the start timing S of the lane change to the timing C, and the position of the left lane line. Time change L2 _SC (t) ′ is shown, and time change L2 _CE (t) ′ on the right side of the lane change target lane CL detected from the crossing timing C to the lane change end timing E and the left side A time change L3 _CE (t) ′ of the position of the lane marking is shown. In the case of this example, after the left and right lane lines to be detected are changed at the straddling timing C, the right lane line L2 and the left lane line L3 of the lane change target lane CL are lost, and each of the lane lines L2 and L3 is lost. A constant value is output as the position. Further, FIG. 3B shows the time change L1 _SC (t) ”of the position of the right lane line of the traveling lane ML detected from the start timing S of the lane change to the timing C straddling, and the left lane line A time change L2 _SC (t) "of the position is shown, and a time change L2 _CE (t)" of the right lane line of the lane change target lane CL detected from the crossing timing C to the lane change end timing E is shown. And the time change L3 _CE (t) "of the position of the left lane marking is shown. In the case of this example, after the left and right lane lines to be detected are changed at the straddling timing C, erroneous detection such as temporarily mistaking the lane line L2 on the right side and the lane line L3 on the left side of the lane change target lane CL is performed. Seen.

  In this way, when the vehicle speed is changed, depending on the high vehicle speed, the approach angle to the lane change target lane, etc., when the vehicle crosses the lane line or after straddling it, the left and right lane lines of the lane change target lane are lost or left and right You may mix up the lane markings. Therefore, in the driving support device 1, in order to prevent such erroneous detection, one lane line on the side where the lane is changed in the traveling lane (a lane that straddles the vehicle, And the lane that is common to the lane change target lane). Then, the component of the driving assistance device 1 is demonstrated concretely.

  The steering angle sensor 10 is a sensor that detects the steering angle of the vehicle (the turning angle of the tire). The steering angle sensor 10 detects the steering angle at regular intervals, and transmits the detected steering angle to the ECU 30.

  The vehicle speed sensor 11 is a sensor that detects the vehicle speed of the vehicle. The vehicle speed sensor 11 detects the vehicle speed at regular intervals, and transmits the detected vehicle speed to the ECU 30.

  The yaw rate sensor 12 is a sensor that detects the yaw rate generated in the vehicle. The yaw rate sensor 12 detects the yaw rate at regular intervals, and transmits the detected yaw rate to the ECU 30.

  The lane marking detection unit 13 detects left and right lane markings constituting the lane. The lane marking detection unit 13 normally detects (recognizes) the lane markings on the left and right of the lane at regular intervals (during lane maintenance support, etc.), and if the lane marking can be detected, calculates the position of the lane marking, etc. The information for each left and right lane marking is transmitted to the ECU 30. This information includes information on whether or not the lane line has been detected, the position of the lane line (particularly the position in the left-right direction), and the like. The position of the lane marking (left-right direction) is the position in the coordinate system described above (particularly, the relative position from the point of sight).

  The lane marking detection unit 13 may be, for example, a detection unit including a camera and an image processing device, or a detection unit including a radar sensor such as a laser radar. The camera and the radar sensor are attached to the center position in the left-right direction at the front part (for example, the front end) of the vehicle. In the case of the lane marking detection unit 13 including a camera and an image processing device, the lane marking detection unit 13 is a camera having a viewing angle that can sufficiently capture the lane markings on the left and right sides of the lane. Then, image processing (edge processing or the like) is performed to extract a lane line, and a coordinate position (particularly, a coordinate position in the horizontal direction) of the extracted lane line is calculated. In the case of the lane marking detection unit 13 composed of a radar sensor, it is a scanning radar sensor that can sufficiently detect the lane markings on the left and right sides of the lane, and the lane markings are detected by detection points (reflection points) in the horizontal direction by the radar sensor. Then, the coordinate position and the like of the detected parcel line are calculated. The position of the lane line to be detected is a position ahead of the vehicle by a certain distance (for example, several tens of meters). This fixed distance changes according to the height at which the camera or the like is mounted on the vehicle, the mounting angle, and the like, and corresponds to the fixed distance at which the gazing point of the coordinate system described above is set. In the following description, it is assumed that the marking line detection unit 13 includes a camera and an image processing device.

  In particular, when the lane line detection unit 13 receives a detection lane line command from the ECU 30 at the start of lane change, the lane line detection unit 13 switches to detection of only one lane line on the lane change side indicated by the detection lane line command. The lane marking position and the like are calculated, and information on the single lane marking is transmitted to the ECU 30. This information includes the position of the lane marking (particularly the position in the left-right direction) and the like. Then, the lane line detection unit 13 returns to the normal detection when a lane change end command is received from the ECU 30 at the end of the lane change.

  An example of a method for detecting only one lane marking in the lane marking detection unit 13 including a camera and an image processing device will be described. When one of the two lane markings on the left and right of the driving lane is specified, a predetermined range is set in the left-right direction at a certain time with respect to the position of the one lane marking detected last time. Then, it is determined whether or not the position of the lane line detected this time by image processing is included in the predetermined range in the left and right direction, the lane line included in the predetermined range is extracted, and the extracted lane line is Detected as the current lane marking. Alternatively, when one of the two lane markings on the left and right of the traveling lane is specified, the position of each lane line detected this time by image processing and the one detected last time are detected at regular intervals. The position of the lane line is compared with each other, and the lane line closest to the position of the one lane line detected last time is detected as the current lane line. In this way, since one lane line is continuously tracked, one lane line can be normally detected from the start to the end of the lane change without losing sight of the one lane line.

In FIG. 4, the lane change side of one lane line L2 on the lane change side of the travel lane ML detected by the lane line detection unit 13 from the start timing S of the lane change to the end timing E of the lane change through the timing C straddling. A time change L2 _SE (t) of the position is shown. Thus, during the lane change, only the common lane line (lane boundary line) L2 between the travel lane ML and the lane change target lane CL becomes the detection target, and is normally detected by the lane line detection unit 13. Before the lane change start timing S, the right lane line L1 and the left lane line L2 of the travel lane ML are detected, and after the lane change end timing E, the lane line L2 on the right side of the lane change target lane CL. The left lane marking L3 is detected.

  The periphery monitoring unit 14 monitors the periphery of the vehicle (front, side, rear, etc.). The surroundings monitoring unit 14 detects (recognizes) objects around the vehicle at regular time intervals, and when the objects can be detected, acquires information on the objects and transmits the information to the ECU 30. This information includes information on whether or not an object (for example, a vehicle, a motorcycle, a bicycle, a pedestrian, a curb, or a guardrail) is present in the vicinity. If an object is present, the position, moving direction, and moving speed of the object. Information. The position of the object is a position in the coordinate system described above. Examples of the peripheral monitoring unit 14 include a detection unit including a camera and an image processing device, and a detection unit including a radar sensor such as a laser radar.

  The steering actuator 20 is an actuator that transmits a rotational driving force by a motor to a steering mechanism via a speed reduction mechanism and applies a steering torque to the steering mechanism. When the steering actuator 20 receives a steering control command from the ECU 30, the steering actuator 20 operates a motor in accordance with the steering control command, and rotationally drives the motor to generate a steering torque. The steering mechanism is operated according to the generated steering torque, and the vehicle tire is steered.

  The ECU 30 includes a CPU [Central Processing Unit], various memories, and the like, and performs overall control of the driving support device 1. In the ECU 30, each application program stored in the memory is loaded and executed by the CPU so that the lane width calculation unit 31, the detection lane line switching unit 33, the target position setting unit 34, the estimated position calculation unit 35, and the steering control unit. 36 is configured. The ECU 30 includes a lane width storage unit 32 in a predetermined area of a readable / writable memory. In the ECU 30, each information is received from each of the sensors 10, 11, 12, the lane marking detection unit 13 and the surrounding monitoring unit 14. The ECU 30 performs processing in each of the units 31, 33, 34, 35, and 36 based on the received information, and transmits a steering control command to the steering actuator 20 as necessary. In addition, each part 31,32,33,34,35,36 of ECU30 has shown only what is required for lane change support, and what is required for other support, such as lane maintenance support and automatic stop support, is abbreviate | omitted. Yes.

  The processing of the lane width calculation unit 31 is performed during the lane maintenance support, but the processing of the other units 32, 33, 34, 35, and 36 is performed when the lane change support is shifted to. When a place where the vehicle is safely changed to a lane and stopped safely is detected based on information from the surroundings monitoring unit 14 during the lane maintenance support, the lane maintenance support is shifted to the lane change support, and the lane change starts. .

  The lane width calculation unit 31 has a function of calculating the lane width of the traveling lane during lane maintenance support. The lane width calculation unit 31 calculates the lane width from the difference between the positions using the positions of the left and right lane lines of the traveling lane detected by the lane line detection unit 13.

  When the lane width calculation unit 31 calculates the lane width, the lane width storage unit 32 stores the lane width. The lane width storage unit 32 may store only the latest one lane width, or may store a plurality of lane widths calculated in a predetermined period.

  The detection lane line switching unit 33 has a function of switching the lane line to be detected by the lane line detection unit 13 when changing lanes. When a place where the vehicle can be safely changed to a lane and can be stopped safely is detected based on information from the surroundings monitoring unit 14 while the lane is maintained, the detection lane line switching unit 33 starts lane change and Judging and identifying one lane line on the side where the lane is to be changed (the lane line that the vehicle straddles during the lane change) to the left and right lane lines of the travel lane, and the detection lane line command indicating the lane line is specified Transmit to the detector 13. When the position of the vehicle reaches the final target position for lane change, the detection lane line switching unit 33 determines that the lane change has ended and transmits a lane change end command to the lane line detection unit 13.

  The target position setting unit 34 has a function of setting a future target position of the vehicle for changing the lane of the vehicle. The target position setting unit 34 uses the position of one lane line detected by the lane line detection unit 13 during the lane change and the lane width stored in the lane width storage unit 32 to determine the future target position of the vehicle. Set. When there are a plurality of lanes on the road, the lane widths of the plurality of lanes are considered to be the same, so the lane width of the traveling lane obtained during the lane maintenance support is used as the lane width of the lane to be changed. The future target position of the vehicle is, for example, the target position of the vehicle after a predetermined time (for example, several seconds such as 3 seconds, 5 seconds, etc.). Position. Since the lane marking detection unit 13 detects the position of the lane marking ahead of a certain distance of the vehicle, the future target position of the vehicle can be set by using the position of the lane marking ahead of the certain distance.

  With reference to FIG. 5, an example of a method for setting a target position using the position of one lane marking and the lane width will be described. FIG. 5 shows a case where a lane change is made from a travel lane ML on which the vehicle V was traveling while traveling on a straight road to a lane change target lane CL adjacent to the left side, and FIG. 5A is a start time of the lane change. FIG. 5B shows a lane change. In this setting method, the center position of the left and right lane markings L2 and L3 of the lane change target lane CL (the distance W / half of the lane width W from the one lane marking L2 detected by the lane marking detector 13 to the left) 2) is defined as the final target position GP for lane change. Then, the vehicle V position at the start of lane change (gaze point BP) to the target position GP is divided into four, and each of the four divided positions P1, P2, P3, P4 (GP) at each stage during lane change. The target position.

  As shown in FIG. 5A, at the start of lane change, the target position setting unit 34 calculates the final target position GP using the position LP and the lane width W of the lane marking L2. Here, first, a distance D1 between the position LP of the lane line L2 and the gazing point BP ahead of the vehicle V by a certain distance is acquired, and a distance obtained by adding a distance W / 2 that is half the lane width W to this distance D1. D2 is acquired, and a target position GP that is a position separated by a distance D2 to the left from the gazing point BP is obtained. This distance D2 is the distance in the left-right direction from the vehicle V (gaze point BP) at the start of the lane change to the final target position GP, and the left and right at which the vehicle V moves from the start of lane change to the end of lane change The distance in the direction. This distance D2 is divided into four, and target positions P1, P2, P3, and P4 for each stage are set. The distance D1 corresponds to the first distance described in the claims, and the distance D2 corresponds to the second distance described in the claims.

As shown in FIG. 5B, during the lane change, the position LP ′ of one lane line L2 detected by the lane line detection unit 13 is updated, and the target position setting unit 34 obtains it at the start of the lane change. Using the distances D1 and D2 and the position LP ′ (particularly, the distance D1 ′ between the position LP ′ and the gazing point BP ′) of the lane line L2 to be updated, the following expressions (1), (2), The target positions P1, P2, P3, and P4 of each stage are calculated by using the expressions (3) and (4).
Target position P1 = D1′−D1 + D2 × 1/4 (1)
Target position P2 = D1′−D1 + D2 × 2/4 (2)
Target position P3 = D1′−D1 + D2 × 3/4 (3)
Target position P4 = D1′−D1 + D2 × 4/4 (4)

  Note that the above setting method is an example, and in addition to this, the target position may be set by another method using the position and lane width of one lane marking. For example, the final target position GP is set at a predetermined distance (for example, several centimeters, 10 cm, 20 cm) to the left from a position that is half the lane width W from one lane line, or the lane width W A position at a predetermined distance on the right side from the half distance position may be set, or each position obtained by dividing the distance D2 into two, three, or five or more may be set as the target position of each stage. Only the final target position GP may be obtained.

  The estimated position calculation unit 35 has a function of estimating the future position of the vehicle according to the current traveling state of the vehicle. Similar to the future target position of the vehicle, the future position of the vehicle is an estimated position of the vehicle after a predetermined time, and is a position with respect to the point of interest ahead of the vehicle by a certain distance. The estimated position calculation unit 35 calculates the estimated position of the vehicle after a predetermined time by using the current vehicle speed of the vehicle detected by the vehicle speed sensor 11 and the current yaw rate of the vehicle detected by the yaw rate sensor 12. As a method for calculating the estimated position of the vehicle, a conventionally known method is applied.

  The steering control unit 36 has a function of performing steering control so that the position of the vehicle is directed toward the target position. The steering control unit 36 calculates a deviation amount (difference) between the future target position of the vehicle set by the target position setting unit 34 and the future estimated position of the vehicle calculated by the estimated position calculation unit 35, A target steering angle for making this deviation amount zero is calculated. As a calculation method of the target steering angle based on the deviation amount, there is a calculation method using, for example, PI [Proportional Integral] control by applying a known method. Then, the steering control unit 36 calculates a deviation amount between the target steering angle and the current steering angle of the vehicle detected by the steering angle sensor 10, and calculates a steering control amount for making this deviation amount zero. . This steering control amount may be a steering angle or a steering torque. The steering control unit 36 transmits a steering control command indicating the steering control amount to the steering actuator 20. Note that this steering control is an example, and other steering control may be performed for the steering control using the future target position of the vehicle and the estimated future position of the vehicle.

  With reference to FIG. 1, operation | movement of the driving assistance apparatus 1 is demonstrated along the flowchart of FIG. FIG. 6 is a flowchart showing a flow of operations of the driving support apparatus 1 of FIG. When it is determined that the driver cannot drive normally and the driving support device 1 is activated, first, lane keeping support is performed.

  Each sensor 10, 11, 12 detects each traveling state of the vehicle, and transmits each detected information to the ECU 30. The ECU 30 receives each detection information. The lane line detection unit 13 detects the lane line on the left side and the right side of the lane during lane maintenance support, acquires information such as the positions of the left and right lane lines that can be detected, and Information is transmitted to ECU30. The ECU 30 receives information on the left and right lane markings. In addition, the periphery monitoring unit 14 monitors the periphery of the vehicle and transmits each piece of information obtained by the monitoring to the ECU 30. The ECU 30 receives the monitoring information.

  During the lane keeping support, the ECU 30 calculates the difference between the position of the left lane line and the position of the right lane line as the lane width, and stores the lane width in the lane width storage unit 32 (S1). Further, the ECU 30 sets the lane on the side where the lane is changed from the travel lane (the place where the vehicle is safely stopped) based on the information of the surrounding monitoring (S2). Then, the lane change to the set side is started (S3).

  The ECU 30 transmits a detection lane line command indicating one lane line on the side where the lane is changed (a lane line that the vehicle straddles during the lane change) to the lane line detection unit 13 at the start of the lane change (S4). When receiving the detection lane marking command, the lane marking detection unit 13 switches to detection of only one lane marking indicated by the detection lane marking command (S4). The lane line detection unit 13 detects one lane line during lane change, acquires information such as the position of one lane line that can be detected, and transmits information about one lane line to the ECU 30. (S4). And ECU30 receives the information of this one division line during lane change.

  At the start of lane change, the ECU 30 obtains the distance D1 from the position of one lane marking on the lane change side, and obtains the distance D2 from the distance D1 and the lane width W stored in the lane width storage unit 32. (S5). Then, the ECU 30 sets a future target position of the vehicle using the position of one lane line, the distance D1, and the distance D2 during the lane change (S5).

  The ECU 30 calculates a future estimated position of the vehicle from the current vehicle speed and yaw rate of the vehicle (S6). Then, the ECU 30 calculates a deviation amount between the target position and the estimated position (S7). Further, the ECU 30 calculates a steering control amount for making the deviation amount zero, and transmits a steering control command indicating the steering control amount to the steering actuator 20 (S8). When the steering actuator 20 receives the steering control command, the steering actuator 20 operates according to the steering control command and applies a steering torque to the steering mechanism (S8). Thereby, the tires of the vehicle are steered, the position of the vehicle is directed to the target position, and the vehicle changes lanes from the travel lane to the lane change target lane.

  The ECU 30 determines whether or not the lane change is completed depending on whether or not the vehicle position has reached the final target position for the lane change (S9). If it is determined in S9 that the lane change has not ended, the process returns to S4 and the operations in S4 to S9 are repeated. If it is determined in S9 that the lane change has been completed, the lane change is completed, and the vehicle position becomes the final target position for the lane change. Thereafter, the driving assistance device 1 performs automatic stop assistance and the like.

  According to this driving support device 1, by detecting only one lane line on the side where the lane is changed (the lane line that the vehicle straddles during the lane change) among the left and right lane lines of the travel lane, The target position for changing the lane from the start to the end of the lane change can be appropriately set using the one lane marking. As a result, appropriate lane changes can be continued.

  Moreover, according to the driving assistance apparatus 1, an appropriate target position can be easily set by using one lane line and the lane width of a lane. In particular, according to the driving support device 1, one lane line that changes during the lane change and the distance D1 from the vehicle (gaze point) acquired at the start of the lane change to the one lane line and the vehicle (gaze point) By using the distance D2 from to the final destination, an appropriate target position can be set.

  As mentioned above, although embodiment which concerns on this invention was described, this invention is implemented in various forms, without being limited to the said embodiment.

  For example, in the present embodiment, the present invention is applied to the lane change support function of the automatic driving device, but may be applied to other lane change support devices or other driving support devices including the lane change support function. In this embodiment, the present invention is applied to the lane change support performed by the automatic driving when the driver cannot drive normally. However, when the lane change instruction operation is performed at the will of the vehicle driver, the driver of the vehicle It may be applied when an instruction operation for automatic driving is performed at will.

  Further, in the present embodiment, the steering actuator is directly controlled to perform the steering control. However, the target position or the like is output to another ECU such as the steering control ECU or the ECU of the electric power steering apparatus, and the other ECU It is good also as a structure which performs steering control.

  In this embodiment, the target position is set using the distance obtained from the lane width (half the lane width, etc.) in addition to the position of one lane line. In addition to the distance obtained from the vehicle width of the vehicle (half the vehicle width, half the vehicle width + α (10 cm, 20 cm, 30 cm, etc.) or a preset constant value (eg, 1 m, 1.5 m), etc. It is also possible to use a configuration that sets the position.When a vehicle width or a constant value is used, the processing of the lane width calculation unit or the like is not required, so that the configuration of the lane keeping support device can be simplified. Instead of calculating the lane width using each position of the lane marking, the current position of the vehicle is detected, and the lane width of the lane in which the vehicle is traveling is obtained from the map information using the map information around the current position. Also good.

  In the present embodiment, the future estimated position of the vehicle is calculated, and the steering control is performed based on the deviation amount between the target position and the estimated position. However, without calculating the estimated position, You may perform other steering control for a position to go to a target position.

  DESCRIPTION OF SYMBOLS 1 ... Driving assistance device, 10 ... Steering angle sensor, 11 ... Vehicle speed sensor, 12 ... Yaw rate sensor, 13 ... Demarcation line detection part, 14 ... Perimeter monitoring part, 20 ... Steering actuator, 30 ... ECU, 31 ... Lane width calculation part , 32 ... Lane width storage section, 33 ... Detection lane marking switching section, 34 ... Target position setting section, 35 ... Estimated position calculation section, 36 ... Steering control section.

Claims (4)

A driving support device that performs steering control for changing lanes from a lane in which a vehicle was traveling to an adjacent lane,
A lane marking detector that detects the lane markings on the left and right of the lane;
A target position setting unit for setting a target position for changing the lane of the vehicle using a lane line detected by the lane line detection unit;
A steering control unit that performs steering control of the vehicle so that the vehicle is directed to the target position set by the target position setting unit;
With
When the lane change is performed, the detection by the lane line detection unit is switched to detection of only one lane line on the lane change side among the left and right lane lines of the traveling lane, and the target position setting unit Is a driving support device that sets a target position using the position of the one lane line detected by the lane line detection unit.   The driving support device according to claim 1, wherein the target position setting unit sets a target position using the lane line of the one lane line and the lane.   The target position setting unit obtains a first distance between the predicted position of the vehicle at the start of lane change and the position of the one lane line detected by the lane line detection unit, and the first distance And a second distance obtained by adding the distance half of the lane width, and the position of the one lane line detected by the lane line detection unit during the lane change, the first distance, and the second distance. The driving assistance device according to claim 2, wherein the target position is set by using the driving assistance device.   The driving support device according to claim 1, wherein the target position setting unit sets a target position using the one lane marking and a vehicle width of the vehicle.

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