Driving support device

Abstract

To appropriately perform driving support for an own vehicle before a crosswalk.SOLUTION: A driving support device 100 includes: a crosswalk detection section 11 for detecting a crosswalk C in front of an own vehicle V; an area setting section 13 for setting, on an opposing lane L2, an obstacle detection area A before the crosswalk C so as to detect an obstacle on the opposing lane L2; an obstacle detection section 14 for detecting presence / absence of the obstacle within the obstacle detection area A; and a driving support section 15 for performing driving support for the own vehicle V when the obstacle is detected within the obstacle detection area A.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present disclosure relates to a driving assistance device that provides driving assistance for a vehicle. [Background technology]

[0002] Conventionally, when a driving assistance device of a vehicle detects a pedestrian or the like attempting to cross a crosswalk, the device performs driving assistance such as deceleration. For example, Patent Document 1 describes a method of determining the presence or absence of a pedestrian near a crosswalk by using images captured by an external camera in addition to images captured by a camera mounted on the vehicle itself, and performing driving assistance such as issuing a notification. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2022-148428 A Summary of the Invention [Problem to be solved by the invention]

[0004] When there is another vehicle in an adjacent lane adjacent to the own lane, a blind spot is created by the other vehicle, which may make it difficult to detect pedestrians, etc., who are trying to cross the crosswalk. In addition, although the above-mentioned Patent Document 1 describes the use of an image captured by an external camera, it may be difficult to obtain such an image captured by an external camera.

[0005] For this reason, the present disclosure describes a driving assistance device that can more appropriately provide driving assistance for the vehicle in front of a pedestrian crossing. [Means for solving the problem]

[0006] A driving assistance device according to one aspect of the present disclosure is, [1] "a driving assistance device that provides driving assistance for a host vehicle, comprising: a crosswalk detection unit that detects a crosswalk ahead of the host vehicle; an area setting unit that sets an obstacle detection area on an adjacent lane adjacent to the host vehicle lane, in front of the detected crosswalk, to detect an obstacle on the adjacent lane; an obstacle detection unit that detects the presence or absence of the obstacle within the set obstacle detection area; and a driving assistance unit that provides the driving assistance including at least one of notifying an occupant of the host vehicle, steering control, and deceleration control of the host vehicle when an obstacle is detected within the obstacle detection area."

[0007] This driving assistance device performs driving assistance when an obstacle is detected in an obstacle detection area set in front of a pedestrian crossing on an adjacent lane. In other words, the driving assistance device performs driving assistance in advance in preparation for the presence of a pedestrian or the like attempting to cross the pedestrian crossing in a situation in which a blind spot is created by an obstacle in the obstacle detection area. In this way, the driving assistance device can more appropriately perform driving assistance for the vehicle in front of a pedestrian crossing.

[0008] The driving assistance device may be [2] "The driving assistance device according to [1] above, in which the area setting unit sets an area having a length of at least two other vehicles along the extension direction of the adjacent lane as the obstacle detection area." For example, a plurality of other vehicles may be lined up as obstacles in front of a pedestrian crossing on an adjacent lane. In this case, the further back the other vehicle is from the host vehicle (the side closer to the pedestrian crossing), the larger the area hidden by the other vehicle immediately in front of it when viewed from the host vehicle. For this reason, the further back the other vehicle is, the more difficult it is to detect it as a other vehicle. In other words, when detecting a other vehicle on an adjacent lane, the closer it is to the host vehicle, the easier it is to detect it as a other vehicle. For this reason, the driving assistance device sets an area having a length of at least two other vehicles as the obstacle detection area for detecting other vehicles. As a result, even if, for example, other vehicles are lined up on the adjacent lane and it is difficult to detect the other vehicle on the far side, the driving assistance device can easily detect the other vehicle located in front. In this way, the driving assistance device can more appropriately detect an obstacle (e.g., another vehicle) located in front of the pedestrian crossing on an adjacent lane. The driving assistance device can then provide driving assistance based on the detected obstacle.

[0009] The driving assistance device may be the driving assistance device according to [1] or [2] above, further comprising: a congestion information acquisition unit that acquires congestion information of the adjacent lane; and the area setting unit determines whether the adjacent lane is congested based on the acquired congestion information; and when the adjacent lane is congested, sets the length of the obstacle detection area along the extension direction of the adjacent lane longer than when the adjacent lane is not congested. When congestion occurs in the adjacent lane, other vehicles are lined up in the adjacent lane. In this case, the further the other vehicle is from the vehicle's perspective, the more the area hidden by the other vehicle immediately in front of it becomes, making detection more difficult. For this reason, when congestion occurs in the adjacent lane, the driving assistance device sets the length of the obstacle detection area to be longer. As a result, the driving assistance device can more appropriately detect other vehicles located in front of a crosswalk on the adjacent lane as obstacles, even when other vehicles are lined up.

[0010] The driving assistance device may be [4] "the driving assistance device according to any one of [1] to [3] above, wherein the area setting unit sets a length of the obstacle detection area along the extension direction of the adjacent lane longer as the distance to the crosswalk increases." Here, for example, due to the influence of noise or the like, it may be difficult to detect an obstacle located farther away from the vehicle. For this reason, the driving assistance device can increase the possibility of detecting an obstacle located in front of the crosswalk on the adjacent lane by setting the length of the obstacle detection area longer as the distance to the crosswalk increases.

[0011] The driving assistance device may be [5] "the driving assistance device according to any one of [1] to [4] above, wherein the area setting unit sets a length of the obstacle detection area along the extension direction of the adjacent lane longer as the vehicle speed of the host vehicle increases." Here, when the vehicle speed of the host vehicle is high, the amount of movement of the obstacle increases relatively, and it may become difficult to detect the obstacle. For this reason, the driving assistance device sets the length of the obstacle detection area longer as the vehicle speed of the host vehicle increases. This enables the driving assistance device to increase the possibility of detecting an obstacle on the adjacent lane that is located in front of a pedestrian crossing.

[0012] The driving assistance device may be [6] "the driving assistance device according to any one of [1] to [5] above, in which the obstacle detection unit detects the presence or absence of another vehicle in the obstacle detection area having a vehicle speed equal to or less than a predetermined vehicle speed threshold, as the presence or absence of the obstacle, and the driving assistance unit performs the driving assistance when the other vehicle having a vehicle speed equal to or less than the vehicle speed threshold is detected in the obstacle detection area." For example, a case in which the vehicle speed of the other vehicle on the adjacent lane is fast is considered to be a situation in which there is no pedestrian or the like attempting to cross a crosswalk. For this reason, the driving assistance device performs driving assistance when a vehicle having a vehicle speed equal to or less than the vehicle speed threshold is detected in the obstacle detection area. This allows the driving assistance device to perform driving assistance in consideration of the possibility of the presence of a pedestrian or the like attempting to cross a crosswalk. Effect of the Invention

[0013] According to one aspect of the present disclosure, driving assistance for the vehicle can be performed more appropriately in front of a pedestrian crossing. [Brief description of the drawings]

[0014] [Figure 1] FIG. 1 is a block diagram illustrating an example of a driving assistance device according to an embodiment. [Diagram 2] FIG. 2 is a top view showing an obstacle detection area set in front of a pedestrian crossing. [Diagram 3] FIG. 3 is a schematic diagram showing a line of oncoming vehicles as seen from a vehicle. [Figure 4] FIG. 4 is a flowchart showing the flow of the driving assistance process performed in the driving assistance device. [Diagram 5] FIG. 5 is a top view showing an obstacle detection area set in front of a pedestrian crossing in the first modified example. [Figure 6] FIG. 6 is a top view showing an obstacle detection area set in front of a pedestrian crossing in the second modified example. [Figure 7] FIG. 7 is a top view showing an obstacle detection area set in front of a pedestrian crossing in the third modified example. [Figure 8] FIG. 8 is a top view showing an obstacle detection area set in front of a pedestrian crossing in the fourth modified example. [Figure 9] FIG. 9 is a diagram showing an example of an obstacle present in front of a pedestrian crossing. [Figure 10] FIG. 10 is a diagram showing another example of an obstacle existing in front of a pedestrian crossing. [Figure 11] FIG. 11 is a diagram showing yet another example of an obstacle present before a pedestrian crossing. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] Hereinafter, exemplary embodiments will be described with reference to the drawings. In each drawing, the same or corresponding elements are denoted by the same reference numerals, and duplicated explanations will be omitted.

[0016] A driving assistance device 100 shown in Fig. 1 is mounted on a host vehicle V and provides driving assistance for the host vehicle V. In this embodiment, the driving assistance device 100 provides driving assistance at a position on the near side of a crosswalk C in front of the host vehicle V as shown in Fig. 2, depending on the presence or absence of an obstacle in front of the crosswalk C. Here, an example will be described in which the obstacle in front of the crosswalk C is another vehicle.

[0017] In this embodiment, as shown in FIG. 2, it is assumed that the oncoming lane L2 is adjacent to the right side of the own lane L1 on which the own vehicle V is traveling. That is, the oncoming lane L2 is an adjacent lane adjacent to the own lane L1. In addition, a crosswalk C exists in front of the own vehicle V so as to cross the own lane L1 and the oncoming lane L2. On the near side of the crosswalk C as seen from the own vehicle V, a first oncoming vehicle V1, a second oncoming vehicle V2, and a third oncoming vehicle V3 are traveling on the oncoming lane L2. The first oncoming vehicle V1 is traveling at a position closest to the crosswalk C, the third oncoming vehicle V3 is traveling at a position closest to the own vehicle V, and the second oncoming vehicle V2 is traveling at a position between the first oncoming vehicle V1 and the third oncoming vehicle V3. That is, the first oncoming vehicle V1 to the third oncoming vehicle V3 are other vehicles on the adjacent lanes.

[0018] In the following description, "near" means the side closer to the vehicle V, and "far" means the side further from the vehicle V. "Longitudinal" means the direction along the extension direction of the vehicle's lane L1 and / or the oncoming lane L2. "Horizontal" means the direction along the lane width direction of the vehicle's lane L1 and / or the oncoming lane L2.

[0019] 1, the driving assistance device 100 includes a vehicle speed sensor 1, an external sensor 2, an HMI [Human Machine Interface] 3, an actuator 4, and an assistance ECU [Electronic Control Unit] 10. The vehicle speed sensor 1 is a detector that detects the vehicle speed of the host vehicle V. The vehicle speed sensor 1 is provided, for example, on the wheels of the host vehicle V or a drive shaft that rotates integrally with the wheels, and detects the rotation speed of the wheels. The vehicle speed sensor 1 transmits vehicle speed information of the host vehicle V to the assistance ECU 10.

[0020] The external sensor 2 is an on-board sensor that detects the external environment of the host vehicle V. The external sensor 2 includes at least a camera. The camera is an imaging device that captures images of the external environment of the host vehicle V. The camera is provided, for example, on the back side of the windshield of the host vehicle V, and captures images of the area in front of the vehicle. The camera transmits imaging information related to the external environment of the host vehicle V to the assistance ECU 10. The camera may be a monocular camera or a stereo camera. Multiple cameras may be provided, and may capture images of the left and right sides of the host vehicle V in addition to the area in front of the vehicle V.

[0021] The external sensor 2 may include a radar sensor. The radar sensor is a detection device that detects objects around the host vehicle V by using radio waves (e.g., millimeter waves) or light. The radar sensor includes, for example, a millimeter wave radar or a lidar (LIDAR: Light Detection and Ranging). The radar sensor transmits radio waves or light to the periphery of the host vehicle V and receives the radio waves or light reflected by the objects. The radar sensor transmits the reception result of the radio waves or light reflected by the objects to the assistance ECU 10.

[0022] The HMI 3 is an interface for inputting and outputting information between the vehicle V and the occupants. The HMI 3 has a display, a speaker, etc. The HMI 3 provides driving guidance and notifications to the driver.

[0023] The actuator 4 is a device used to control the traveling of the host vehicle V. The actuator 4 includes at least a brake actuator that controls the brakes of the host vehicle V, and a steering actuator that controls the steering of the host vehicle V.

[0024] The assistance ECU 10 is an electronic control unit having a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), etc. The assistance ECU 10, for example, loads a program recorded in the ROM into the RAM and executes the program loaded into the RAM with the CPU to realize various functions. The assistance ECU 10 may be composed of multiple electronic units. Functionally, the assistance ECU 10 includes a crosswalk detection unit 11, a traffic congestion information acquisition unit 12, an area setting unit 13, an obstacle detection unit 14, and a driving assistance unit 15.

[0025] The crosswalk detection unit 11 detects a crosswalk C ahead of the vehicle V. In this embodiment, the crosswalk detection unit 11 can detect the presence or absence of a crosswalk C by using pattern matching or an image recognition technique such as Semantic Segmentation based on, for example, imaging information (captured image) from the camera of the external sensor 2. The crosswalk detection unit 11 also detects the distance to the crosswalk C based on the imaging information from the camera. The crosswalk detection unit 11 can detect the distance to the crosswalk C by, for example, using the Y coordinate (ordinate) of the captured image or the size of the crosswalk area extracted by image recognition.

[0026] The crosswalk detection unit 11 may be configured to detect a crosswalk C that exists within a predetermined distance from the vehicle V. In addition to using imaging information from a camera, the crosswalk detection unit 11 may detect the presence or absence of a crosswalk C ahead of the vehicle V and the distance to the crosswalk C based on map information.

[0027] In this embodiment, the crosswalk detection unit 11 detects a crosswalk without a traffic light as the crosswalk C. The crosswalk detection unit 11 may determine the presence or absence of a traffic light by using pattern matching or image recognition technology based on image information of a camera, for example. Alternatively, the crosswalk detection unit 11 may determine the presence or absence of a traffic light based on installation information of a traffic light included in map information.

[0028] The traffic congestion information acquisition unit 12 acquires traffic congestion information for the oncoming lane L2. Here, the traffic congestion information indicates the density of vehicles on the travel lane. The traffic congestion information acquisition unit 12 may acquire traffic congestion information used in a navigation system, for example, as the traffic congestion information for the oncoming lane L2. Alternatively, the traffic congestion information acquisition unit 12 may perform vehicle-to-vehicle communication with other vehicles traveling in the vicinity. Then, the traffic congestion information acquisition unit 12 may generate (acquire) traffic congestion information for the oncoming lane L2 based on the result of the vehicle-to-vehicle communication.

[0029] 2, the area setting unit 13 sets an obstacle detection area A on the oncoming lane L2, in front of the crosswalk C detected by the crosswalk detection unit 11. The obstacle detection area A is an area in which oncoming vehicles (other vehicles, obstacles) on the oncoming lane L2 are detected.

[0030] Here, the area setting unit 13 detects the lane width of the oncoming lane L2 using a known image recognition technique based on the imaging information of the camera of the external sensor 2. The area setting unit 13 sets the width of the obstacle detection area A (the length in the width direction of the oncoming lane L2) to, for example, the same length as the lane width of the detected oncoming lane L2, or a length obtained by multiplying the lane width of the detected oncoming lane L2 by a predetermined value. Note that there may be a case where the lane width of the oncoming lane L2 cannot be detected. In this case, the area setting unit 13 detects the lane width of the own lane L1 using a known image recognition technique based on the imaging information of the camera of the external sensor 2. The area setting unit 13 sets the width of the obstacle detection area A to, for example, the same length as the lane width of the detected own lane L1, or a length obtained by multiplying the lane width of the detected own lane L1 by a predetermined value.

[0031] The area setting unit 13 also sets a back boundary line A2 of the obstacle detection area A at the position of the near edge of the crosswalk C. The back boundary line A2 is the far edge of the obstacle detection area A. The area setting unit 13 sets a front boundary line A1 of the obstacle detection area A at a position closer to the front than the back boundary line A2. The front boundary line A1 is the near edge of the obstacle detection area A.

[0032] The area setting unit 13 sets the length B1 of the obstacle detection area A along the extension direction of the oncoming lane L2 to a length equal to or greater than two oncoming vehicles (other vehicles) to be detected. In other words, the area setting unit 13 sets the obstacle detection area A along the extension direction of the oncoming lane L2 to a length equal to or greater than two oncoming vehicles to be detected.

[0033] The length B1 of the obstacle detection area A is the length from the near side boundary line A1 to the far side boundary line A2 of the obstacle detection area A that is provided along the extension direction of the vehicle lane L1. The oncoming vehicle to be detected is assumed to be a standard passenger car. The standard passenger car is a vehicle with a total length of about 5 m. The length B1 of the obstacle detection area A may be set to a length of about 30 m or less, for example, and more preferably to a length of about 15 m to 20 m.

[0034] For example, the distance from the vehicle V to the crosswalk C is 60 m. The length B1 of the obstacle detection area A set by the area setting unit 13 is 15 m. In this case, the obstacle detection area A is set on the oncoming traffic lane L2 between a position 45 m away from the vehicle V (the position where the near side boundary line A1 is set) and a position 60 m away from the vehicle V (the position where the far side boundary line A2 is set).

[0035] The area setting unit 13 can change the set length in the vertical direction of the obstacle detection area A based on various conditions. That is, the area setting unit 13 can change the position of the set near side boundary line A1. As a first change method, for example, the area setting unit 13 can set the length in the vertical direction of the obstacle detection area A depending on the presence or absence of congestion in the oncoming lane L2. Here, the area setting unit 13 determines whether or not the oncoming lane L2 is congested based on the congestion information acquired by the congestion information acquisition unit 12. Here, the case where the oncoming lane L2 is congested may be, for example, a case where the density of oncoming vehicles on the oncoming lane L2 is equal to or higher than a predetermined density. When the oncoming lane L2 is congested, the area setting unit 13 sets the length in the vertical direction of the obstacle detection area A to be longer than when the oncoming lane L2 is not congested.

[0036] As a second change method, for example, the area setting unit 13 sets the vertical length of the obstacle detection area A to be longer as the distance to the crosswalk C detected by the crosswalk detection unit 11 is longer. As a third change method, for example, the area setting unit 13 acquires the vehicle speed of the host vehicle V based on the detection result of the vehicle speed sensor 1. Then, the area setting unit 13 sets the vertical length of the obstacle detection area A to be longer as the vehicle speed of the host vehicle V is faster.

[0037] The area setting unit 13 may set the vertical length of the obstacle detection area A based on any one of the first change direction to third change methods described above, or may set the vertical length of the obstacle detection area A by combining two or more of these methods.

[0038] The obstacle detection unit 14 detects the presence or absence of an oncoming vehicle as an obstacle within the obstacle detection area A set by the area setting unit 13. Here, the obstacle detection unit 14 detects the presence or absence of an oncoming vehicle traveling at or below a predetermined vehicle speed threshold within the obstacle detection area A. This vehicle speed threshold may be set to a value of, for example, 20 km / h or less to 15 km / h or less.

[0039] More specifically, first, the obstacle detection unit 14 detects the vehicle speed of other vehicles around the host vehicle V, the longitudinal distance from the host vehicle V to the other vehicles, and the lateral position of the other vehicles relative to the host vehicle V, based on the detection information of the external sensor 2. For example, the obstacle detection unit 14 can detect other vehicles using pattern matching or image recognition technology using imaging information from a camera. Alternatively, the obstacle detection unit 14 can detect other vehicles using a well-known method based on the reception results of a millimeter wave radar or LIDAR.

[0040] Then, the obstacle detection unit 14 extracts other vehicles having a vehicle speed equal to or lower than a predetermined vehicle speed threshold from among all the detected other vehicles. The obstacle detection unit 14 can determine whether or not the extracted other vehicles are present within the obstacle detection area A based on the detected longitudinal distance from the host vehicle V to the other vehicles and the lateral position of the other vehicles relative to the host vehicle V.

[0041] 2, suppose that the first oncoming vehicle V1 to the third oncoming vehicle V3 are detected and their vehicle speeds are equal to or lower than the vehicle speed threshold. In this case, the obstacle detection unit 14 determines that the first oncoming vehicle V1 and the second oncoming vehicle V2 are present within the obstacle detection area A.

[0042] Here, there may be cases where a number of other vehicles are traveling in a line in an adjacent lane adjacent to the lane in which the vehicle V is traveling. In this case, when the vehicle V looks at the other vehicles in the adjacent lane, the further the vehicle is from the vehicle V, the larger the area that is hidden by the vehicle immediately in front of it. For example, in the situation shown in FIG. 2, as shown in FIG. 3, the first oncoming vehicle V1 is hidden by the second oncoming vehicle V2, so only a small part of it is visible from the vehicle V. Also, the second oncoming vehicle V2 is partially hidden by the third oncoming vehicle V3.

[0043] When detecting a vehicle based on the detection result of the external sensor 2, it is common to detect the object as a vehicle based on the shape of the detected object. In other words, when the obstacle detection unit 14 detects a series of oncoming vehicles based on the detection result of the external sensor 2, it is more difficult to detect the oncoming vehicle at the back. For this reason, when detecting an oncoming vehicle that exists in front of the crosswalk C on the oncoming lane L2, the longer the vertical length of the obstacle detection area A, the more oncoming vehicles that exist closer can be included in the vehicles to be detected. As described above, the closer the oncoming vehicle is, the easier it is to see it from the host vehicle V. This increases the possibility that the obstacle detection unit 14 can detect an oncoming vehicle that exists in front of the crosswalk C on the oncoming lane L2 as an oncoming vehicle.

[0044] When the obstacle detection unit 14 detects one or more oncoming vehicles traveling at or below the vehicle speed threshold within the obstacle detection area A, the driving assistance unit 15 performs driving assistance for the host vehicle V. This driving assistance is assistance for the case where a pedestrian or the like who is about to cross the crosswalk C is present in an area that is a blind spot caused by an oncoming vehicle on the oncoming lane L2.

[0045] The driving support unit 15 performs at least one of the following driving support: notifying the occupants of the host vehicle V, steering control of the host vehicle V, and deceleration control of the host vehicle V. The driving support unit 15 can notify the occupants of the host vehicle V using the HMI 3. This notification may be a notification to call attention to the possibility of a pedestrian or the like attempting to cross the crosswalk C. The driving support unit 15 can perform steering control and deceleration control of the host vehicle V using the actuator 4. This steering control may be, for example, steering the host vehicle V away from the oncoming lane L2 in preparation for a pedestrian or the like jumping out from behind an oncoming vehicle.

[0046] The driving assistance unit 15 can provide driving assistance when a predetermined assistance timing condition is satisfied. For example, the assistance timing condition may be determined using a time required for the vehicle V to reach the crosswalk C. For example, the assistance timing condition may be "the time required for the vehicle V to reach the crosswalk C is within a predetermined range." In this case, for example, the driving assistance unit 15 calculates the time required for the vehicle V to reach the crosswalk C based on the distance to the crosswalk C detected by the crosswalk detection unit 11 and the vehicle speed of the vehicle V obtained based on the detection result of the vehicle speed sensor 1. The driving assistance unit 15 provides driving assistance when the calculated time required for the vehicle V to reach the crosswalk C satisfies the assistance timing condition. As an example, the predetermined assistance timing condition may be a case where the time required for the vehicle V to reach the crosswalk C is 5 seconds or less. As the assistance timing condition, various conditions may be determined in advance based on the distance to the crosswalk C in addition to the time required for the vehicle V to reach the crosswalk C.

[0047] Next, a flow of the driving assistance process performed by the driving assistance device 100 in front of a pedestrian crossing will be described. The driving assistance performed by the driving assistance device 100 here is driving assistance for a case where a pedestrian or the like is about to cross the pedestrian crossing behind an oncoming vehicle. Here, the driving assistance performed by the driving assistance device 100 will be described, but driving assistance different from the driving assistance performed by the driving assistance device 100 may be performed by another driving assistance device.

[0048] 4, the crosswalk detection unit 11 of the driving assistance device 100 detects whether or not there is a crosswalk without a traffic light ahead of the vehicle V (S101). If a crosswalk without a traffic light exists, the crosswalk detection unit 11 also detects the distance to the crosswalk. If a crosswalk without a traffic light is not detected (S101: NO), the driving assistance device 100 restarts the process from the start after a predetermined time.

[0049] When a crosswalk C without a traffic light is detected (S101: YES), the area setting unit 13 sets an obstacle detection area A on the oncoming lane L2 on the near side of the crosswalk C (S102). The obstacle detection unit 14 detects the presence or absence of an oncoming vehicle (low-speed oncoming vehicle) traveling at or below the vehicle speed threshold in the obstacle detection area A (S103). When there is no oncoming vehicle traveling at or below the vehicle speed threshold (S103: NO), the driving assistance device 100 restarts the process from the start after a predetermined time.

[0050] If there is an oncoming vehicle traveling at or below the vehicle speed threshold (S103: YES), the driving assistance unit 15 determines whether or not an assistance timing condition for performing driving assistance is met based on the distance to the crosswalk C (S104). If the assistance timing condition is not met (S104: NO), the driving assistance device 100 restarts the process from the start after a predetermined time. If the assistance timing condition is met (S104: YES), the driving assistance unit 15 performs driving assistance for the host vehicle V (S105).

[0051] As described above, the driving assistance device 100 performs driving assistance when an oncoming vehicle is detected in the obstacle detection area A set on the oncoming lane L2 in front of the crosswalk C. In other words, the driving assistance device 100 performs driving assistance in advance in preparation for the presence of a pedestrian or the like attempting to cross the crosswalk C in a situation in which a blind spot is created by an oncoming vehicle in the obstacle detection area A. In this way, the driving assistance device 100 can more appropriately perform driving assistance for the host vehicle V in front of the crosswalk C.

[0052] For example, there may be a line of oncoming vehicles in front of a pedestrian crossing on the oncoming lane L2. In this case, as described with reference to FIG. 3, the further back (closer to the pedestrian crossing) an oncoming vehicle is when viewed from the vehicle V, the larger the area that is hidden by the oncoming vehicle immediately in front of it. For this reason, the further back the oncoming vehicle is, the more difficult it is to detect it as an oncoming vehicle. In other words, when detecting an oncoming vehicle on the oncoming lane L2, the closer it is to the vehicle V, the easier it is to detect it as an oncoming vehicle. For this reason, the driving assistance device 100 sets an area with a length of at least two oncoming vehicles as the obstacle detection area A in which oncoming vehicles are detected.

[0053] This makes it easier for the driving assistance device 100 to detect an oncoming vehicle located in front even when, for example, oncoming vehicles are lined up on the oncoming lane L2 and it is difficult to detect an oncoming vehicle at the back. For example, in the example shown in FIG. 2, even when a first oncoming vehicle V1 cannot be detected as an oncoming vehicle located in front of the crosswalk C, it is more likely that the second oncoming vehicle V2 can be detected. In this way, the driving assistance device 100 can more appropriately detect an oncoming vehicle located in front of the crosswalk C on the oncoming lane L2. Then, the driving assistance device 100 can perform driving assistance based on the detected oncoming vehicle.

[0054] When congestion occurs in the oncoming lane L2, a situation occurs in which oncoming vehicles are lined up in the oncoming lane L2. In this case, the further back an oncoming vehicle is from the host vehicle V, the larger the area that is hidden by the oncoming vehicle immediately in front of it, making detection more difficult. For this reason, when congestion occurs in the oncoming lane L2, the driving assistance device 100 sets the vertical length of the obstacle detection area A to be long. This allows the driving assistance device 100 to more appropriately detect oncoming vehicles located in front of the crosswalk C on the oncoming lane L2, even when other vehicles are lined up.

[0055] For example, due to the influence of noise, it may be difficult to detect an oncoming vehicle located far away from the vehicle V. For this reason, the area setting unit 13 sets the vertical length of the obstacle detection area A to be longer as the distance to the crosswalk C is longer. This allows the driving assistance device 100 to increase the possibility of detecting an oncoming vehicle located in front of the crosswalk C on the oncoming lane L2. However, if the vertical length of the obstacle detection area A is longer, the possibility of erroneously detecting an oncoming vehicle may increase. For this reason, from various viewpoints, such as wanting to suppress such erroneous detection, a configuration may be adopted in which the vertical length of the obstacle detection area A is set to be shorter as the distance to the crosswalk C is longer.

[0056] When the vehicle speed of the host vehicle V is high, the movement amount of the oncoming vehicle becomes relatively large, and it may become difficult to detect the oncoming vehicle. For this reason, the area setting unit 13 sets the vertical length of the obstacle detection area A to be longer as the vehicle speed of the host vehicle V is faster. This allows the driving assistance device 100 to increase the possibility of detecting an oncoming vehicle located in front of the crosswalk C on the oncoming lane L2. However, if the vertical length of the obstacle detection area A is long, the possibility of erroneously detecting an oncoming vehicle may increase. For this reason, from various viewpoints, such as wanting to suppress such erroneous detection, a configuration may be adopted in which the vertical length of the obstacle detection area A is set to be shorter as the vehicle speed of the host vehicle V is faster.

[0057] For example, the speed of an oncoming vehicle on the oncoming lane L2 may be fast. When the oncoming vehicle is fast, it is considered that there is no pedestrian or the like attempting to cross the crosswalk C. For this reason, the driving assistance unit 15 performs driving assistance when an oncoming vehicle with a speed equal to or less than the vehicle speed threshold is detected in the obstacle detection area A. This allows the driving assistance device 100 to perform driving assistance taking into consideration the possibility of the presence of a pedestrian or the like attempting to cross the crosswalk C.

[0058] Although the embodiment of the present disclosure has been described above, the present disclosure is not limited to the above embodiment. For example, in the above embodiment, an oncoming vehicle existing in front of the crosswalk C on the oncoming lane L2 is detected. The driving support device 100 is not limited to detecting an oncoming vehicle on the oncoming lane L2 facing the own lane L1. Hereinafter, a first modification and a second modification of the driving support device 100 that detect other vehicles other than the oncoming vehicle on the oncoming lane L2 will be described.

[0059] (Variation 1) In the first modified example, for example, as shown in FIG. 5, it is assumed that an adjacent lane L11 is adjacent to the right side of the own lane L1 in which the own vehicle V is traveling. The adjacent lane L11 is a lane in which vehicles travel in the same direction as the own lane L1. That is, the own vehicle V is traveling on the left lane (own lane L1) of a two-lane road on each side. A first other vehicle V11, a second other vehicle V12, and a third other vehicle V13 are traveling on the adjacent lane L11 on the near side of the crosswalk C as seen from the own vehicle V. The first other vehicle V11 is traveling at a position closest to the crosswalk C, the third other vehicle V13 is traveling at a position closest to the own vehicle V, and the second other vehicle V12 is traveling at a position between the first other vehicle V11 and the third other vehicle V13. That is, the first other vehicle V11 to the third other vehicle V13 are other vehicles on the adjacent lane.

[0060] In this case, the driving assistance device 100 provides driving assistance based on the adjacent lane L11 and other vehicles (first other vehicle V11 to third other vehicle V13) instead of the oncoming lane L2 and oncoming vehicles (first oncoming vehicle V1 to third oncoming vehicle V3) in the above-described embodiment.

[0061] Specifically, the congestion information acquisition unit 12 acquires congestion information for the adjacent lane L11 instead of the oncoming lane L2 described in the above embodiment. The area setting unit 13 sets an obstacle detection area A on the adjacent lane L11 on the near side of the crosswalk C instead of the oncoming lane L2 described in the above embodiment. The obstacle detection unit 14 detects other vehicles in the obstacle detection area A instead of the oncoming vehicles described in the above embodiment. The driving assistance unit 15 provides driving assistance for the host vehicle V depending on the presence or absence of other vehicles in the obstacle detection area A on the adjacent lane L11.

[0062] Even in this case, the driving assistance device 100 can detect another vehicle on the adjacent lane L11 in front of the crosswalk C, and can provide driving assistance for the host vehicle V more appropriately, as in the above-described embodiment.

[0063] (Variation 2) In the second modified example, for example, as shown in FIG. 6, it is assumed that an adjacent lane L12 is adjacent to the left side of the own lane L1 in which the own vehicle V is traveling. The adjacent lane L12 is a lane in which vehicles travel in the same direction as the own lane L1. That is, the own vehicle V is traveling on the right lane (own lane L1) of a two-lane road on each side. A first other vehicle V21, a second other vehicle V22, and a third other vehicle V23 are traveling on the adjacent lane L12 on the near side of the crosswalk C as seen from the own vehicle V. The first other vehicle V21 is traveling at a position closest to the crosswalk C, the third other vehicle V23 is traveling at a position closest to the own vehicle V, and the second other vehicle V22 is traveling at a position between the first other vehicle V21 and the third other vehicle V23. That is, the first other vehicle V21 to the third other vehicle V23 are other vehicles on the adjacent lane.

[0064] In this case, the driving assistance device 100 provides driving assistance based on the adjacent lane L12 and other vehicles (first other vehicle V21 to third other vehicle V23) instead of the oncoming lane L2 and oncoming vehicles (first oncoming vehicle V1 to third oncoming vehicle V3) in the above-described embodiment.

[0065] Specifically, the congestion information acquisition unit 12 acquires congestion information for the adjacent lane L12 instead of the oncoming lane L2 described in the above embodiment. The area setting unit 13 sets an obstacle detection area A on the adjacent lane L12 on the near side of the crosswalk C instead of the oncoming lane L2 described in the above embodiment. The obstacle detection unit 14 detects other vehicles in the obstacle detection area A instead of the oncoming vehicles described in the above embodiment. The driving assistance unit 15 provides driving assistance for the host vehicle V depending on the presence or absence of other vehicles in the obstacle detection area A on the adjacent lane L12.

[0066] Even in this case, the driving assistance device 100 can detect another vehicle on the adjacent lane L12 in front of the crosswalk C, and can provide driving assistance for the host vehicle V more appropriately, as in the above-described embodiment.

[0067] Here, in the above embodiment and each modification, another vehicle traveling in an adjacent lane adjacent to the own lane L1 is detected. However, the present invention is not limited to this, and the driving support device 100 may detect another vehicle parked (stopped) so as to straddle the adjacent lane and the road shoulder as another vehicle in the adjacent lane. Hereinafter, a third modification and a fourth modification of the driving support device 100 capable of detecting another vehicle parked so as to straddle the adjacent lane and the road shoulder will be described.

[0068] (Variation 3) In the third modified example, as shown in FIG. 7, it is assumed that the oncoming lane L2 is adjacent to the right side of the own lane L1 on which the own vehicle V is traveling. That is, the oncoming lane L2 is an adjacent lane adjacent to the own lane L1. On the near side of the crosswalk C as seen from the own vehicle V, the first other vehicle V31, the second other vehicle V32, and the third other vehicle V33 are parked so as to straddle the oncoming lane L2 and the right shoulder La of the oncoming lane L2. The first other vehicle V31 is parked in a position closest to the crosswalk C, the third other vehicle V33 is parked in a position closest to the own vehicle V, and the second other vehicle V32 is parked in a position between the first other vehicle V31 and the third other vehicle V33. That is, the first other vehicle V31 to the third other vehicle V33, which are each parked, are other vehicles on the adjacent lanes.

[0069] In this case, the driving assistance device 100 provides driving assistance based on other vehicles (first other vehicle V31 to third other vehicle V33) parked across the oncoming lane L2 and the shoulder La, instead of the oncoming vehicles (first oncoming vehicle V1 to third oncoming vehicle V3) in the above-described embodiment.

[0070] Specifically, the area setting unit 13 sets an obstacle detection area AX on the oncoming lane L2 on the near side of the crosswalk C, similar to the obstacle detection area A described in the above embodiment. At this time, the area setting unit 13 sets an obstacle detection area AX that is expanded to the right from the oncoming lane L2 so that the right boundary line includes the shoulder La, in order to detect other vehicles parked so as to straddle the oncoming lane L2 and the road shoulder La. The obstacle detection unit 14 detects other vehicles in the obstacle detection area AX, instead of the oncoming vehicles described in the above embodiment. The driving assistance unit 15 provides driving assistance for the host vehicle V depending on the presence or absence of other vehicles (parked vehicles) in the obstacle detection area AX that is set to straddle the oncoming lane L2 and the road shoulder La.

[0071] In this way, the driving assistance device 100 detects other vehicles on the oncoming lane L2, including other vehicles parked so as to straddle the oncoming lane L2 and the road shoulder La and with a part of the vehicle entering the oncoming lane L2. Even in this case, the driving assistance device 100 can detect other vehicles parked so as to straddle the oncoming lane L2 and the road shoulder La in front of the crosswalk C, as in the above-mentioned embodiment, and can more appropriately perform driving assistance for the host vehicle V.

[0072] (Variation 4) In the fourth modified example, for example, as shown in Fig. 8, it is assumed that the adjacent lane L12 is adjacent to the left side of the own lane L1 on which the own vehicle V is traveling. On the near side of the crosswalk C as seen from the own vehicle V, a first other vehicle V41, a second other vehicle V42, and a third other vehicle V43 are parked so as to straddle the adjacent lane L12 and the left shoulder Lb of the adjacent lane L12. The first other vehicle V41 is parked in a position closest to the crosswalk C, the third other vehicle V43 is parked in a position closest to the own vehicle V, and the second other vehicle V42 is parked in a position between the first other vehicle V41 and the third other vehicle V43. In other words, the first other vehicle V41 to the third other vehicle V43, which are each parked, are other vehicles on the adjacent lanes.

[0073] In this case, the driving assistance device 100 provides driving assistance based on other vehicles (first other vehicle V41 to third other vehicle V43) parked across the adjacent lane L12 and the shoulder Lb, instead of the oncoming vehicles (first oncoming vehicle V1 to third oncoming vehicle V3) in the above-described embodiment.

[0074] Specifically, the area setting unit 13 sets an obstacle detection area AY on the adjacent lane L12 on the near side of the crosswalk C, similar to the obstacle detection area A described in the above embodiment. At this time, the area setting unit 13 sets the obstacle detection area AY expanded leftward from the adjacent lane L12 so that the left boundary line includes the road shoulder Lb in order to detect other vehicles parked straddling the oncoming lane L2 and the road shoulder Lb. The obstacle detection unit 14 detects other vehicles in the obstacle detection area AY, instead of the oncoming vehicles described in the above embodiment. The driving assistance unit 15 performs driving assistance for the host vehicle V depending on the presence or absence of other vehicles (parked vehicles) in the obstacle detection area AY set to straddle the oncoming lane L2 and the road shoulder Lb.

[0075] In this way, the driving assistance device 100 detects other vehicles on the adjacent lane L12, including other vehicles parked so as to straddle the adjacent lane L12 and the road shoulder Lb and with a part of the vehicle entering the adjacent lane L12. Even in this case, the driving assistance device 100 can detect other vehicles parked so as to straddle the adjacent lane L12 and the road shoulder Lb in front of the crosswalk C, as in the above-mentioned embodiment, and can more appropriately perform driving assistance for the host vehicle V.

[0076] In the above embodiment and each modified example, the obstacle detection unit 14 detects a vehicle as an obstacle in the obstacle detection area A. The obstacle detection unit 14 is not limited to detecting a vehicle as an obstacle. For example, as shown in FIG. 9, a large obstacle W1 may be present on the near side of the crosswalk on the oncoming lane L2. Also, as shown in FIG. 10, a series of obstacles W11 to W13 may be present on the near side of the crosswalk on the oncoming lane L2. Examples of these obstacles W1, W11 to W13 include heavy machinery and signs placed for road construction, as well as objects other than vehicles. Also, as shown in FIG. 11, a fallen tree W21 that was grown on the side of the road and fell may be present on the near side of the crosswalk on the oncoming lane L2. The obstacle detection unit 14 may detect, for example, obstacles W1, W11 to W13 such as heavy machinery, and a fallen tree W21, as obstacles. As a result, the driving assistance device 100 can provide driving assistance for the host vehicle V based on the presence or absence of an obstacle other than the vehicle, similarly to the above-described embodiment and each of the modified examples.

[0077] At least some of the embodiments and various modified examples described above may be combined in any desired manner. [Explanation of symbols]

[0078] 11... pedestrian crossing detection unit, 12... traffic congestion information acquisition unit, 13... area setting unit, 14... obstacle detection unit, 15... driving assistance unit, 100... driving assistance device, A, AX, AY... obstacle detection area, C... pedestrian crossing, L1... own vehicle lane, L2... oncoming lane (adjacent lane), L11, L12... adjacent lanes, V... own vehicle, V1... first oncoming vehicle (other vehicle, obstacle), V2... second oncoming vehicle Oncoming vehicle (other vehicle, obstacle), V3...third oncoming vehicle (other vehicle, obstacle), V11, V21, V31, V41...first other vehicle (other vehicle, obstacle), V12, V22, V32, V42...second other vehicle (other vehicle, obstacle), V13, V23, V33, V43...third other vehicle (other vehicle, obstacle), W1, W11 to W13...obstacle, W21...fallen tree (obstacle).

Claims

1. A driving assistance device that provides driving assistance for a vehicle, a crosswalk detection unit that detects a crosswalk in front of the vehicle; an area setting unit that sets an obstacle detection area on an adjacent lane adjacent to the own lane, on a front side of the detected pedestrian crossing, for detecting an obstacle on the adjacent lane; an obstacle detection unit that detects the presence or absence of an obstacle within the set obstacle detection area; a driving assistance unit that performs the driving assistance including at least one of notifying an occupant of the host vehicle, steering control, and deceleration control when the obstacle is detected within the obstacle detection area; and A driving assistance device comprising:

2. The driving assistance device according to claim 1 , wherein the area setting unit sets, as the obstacle detection area, an area having a length corresponding to at least two other vehicles along an extension direction of the adjacent lane.

3. A traffic congestion information acquisition unit that acquires traffic congestion information of the adjacent lanes is further provided, The area setting unit is determining whether the adjacent lane is congested based on the acquired congestion information; 2. The driving assistance device according to claim 1, wherein when the adjacent lane is congested, a length of the obstacle detection area along the extension direction of the adjacent lane is set to be longer than when the adjacent lane is not congested.

4. The driving assistance device according to claim 1 , wherein the area setting unit sets a length of the obstacle detection area along an extension direction of the adjacent lane to be longer as the distance to the pedestrian crossing increases.

5. The driving assistance device according to claim 1 , wherein the area setting unit sets a length of the obstacle detection area along an extension direction of the adjacent lane to be longer as the vehicle speed of the host vehicle increases.

6. The obstacle detection unit detects the presence or absence of another vehicle in the obstacle detection area having a vehicle speed equal to or lower than a predetermined vehicle speed threshold, The driving assistance device according to claim 1 , wherein the driving assistance unit performs the driving assistance when the other vehicle is detected within the obstacle detection area at a vehicle speed equal to or lower than the vehicle speed threshold.

Images