Leading vehicle determination method and leading vehicle determination device

Abstract

To improve the accuracy of determining a preceding vehicle ahead of the host vehicle, using map data in which road shapes are expressed in road units by arrangement of a plurality of nodes.SOLUTION: A controller 16 detects a mobile object that moves ahead of a host vehicle 1 in the same direction as the host vehicle, extracts from map data 12 an opposite road shape 31 that represents the road shape of an opposite road to the road on which an opposite vehicle to the host vehicle 1 travels, parallel shifts the opposite road shape 31 so that a point on the opposite road shape 31 near the vehicle position matches the vehicle position, and determines whether or not the mobile object is a preceding vehicle ahead of the host vehicle, on the basis of the degree of deviation in the road width direction between the mobile object and the opposite road shape 32 after parallel shifting.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a method and an apparatus for determining a preceding vehicle. [Background technology]

[0002] Patent document 1 describes a technology that reads position data of nodes, which are road markings located before and after the vehicle's current position, from a road map database, estimates the shape of the vehicle's road from multiple nodes, and controls the headlight illumination. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 4363640 specification Summary of the Invention [Problem to be solved by the invention]

[0004] In map data in which road shapes are represented by an array of multiple nodes on a road-by-road basis, each node indicates a position near the center of the road. Therefore, in places where the number of lanes increases, such as near the entrance to an intersection, the position of the node in the lane width direction also changes in the direction in which the number of lanes increases, so the shape represented by the array of nodes differs from the actual lane shape. Therefore, if a preceding vehicle is determined based on the road shape in the map data, there is a risk of misidentifying the preceding vehicle. The present invention aims to improve the accuracy of determining a vehicle ahead of the host vehicle by using map data in which road shapes are expressed on a road-by-road basis by an arrangement of multiple nodes. [Means for solving the problem]

[0005] In one embodiment of the present invention, a method for determining a preceding vehicle detects the vehicle's current position, that is, the vehicle position; detects a moving object ahead of the vehicle moving in the same direction as the vehicle's direction of travel; detects whether an intersection exists within a first predetermined distance ahead of the vehicle based on map data in which road shapes are expressed on a road-by-road basis using an arrangement of multiple nodes and the vehicle position; if it is detected that an intersection exists within the first predetermined distance ahead of the vehicle, extracts from the map data the shape of the oncoming road along which an oncoming vehicle is traveling; translates the shape of the oncoming road so that a point on the shape of the oncoming road near the vehicle position becomes the vehicle position; and determines whether the moving object is a preceding vehicle of the vehicle based on the degree of deviation in the road width direction between the moving object and the shape of the oncoming road after the translation. [Effects of the Invention]

[0006] According to the present invention, it is possible to improve the accuracy of determining a vehicle ahead of the host vehicle by using map data in which road shapes are expressed on a road-by-road basis by an arrangement of a plurality of nodes. [Brief explanation of the drawings]

[0007] [Figure 1] 1 is a diagram showing an example of a schematic configuration of a vehicle equipped with a cruise control device according to an embodiment; [Figure 2] 1A and 1B are explanatory diagrams illustrating an outline of a preceding vehicle determination method according to an embodiment. [Figure 3] 2 is a block diagram illustrating an example of a functional configuration of a controller in FIG. 1. FIG. [Figure 4] 10 is an explanatory diagram of an example of a method for calculating the amount of deviation between the shape of an oncoming road after translation and the shape of the road on which the vehicle is traveling. FIG. [Figure 5] 10(a) and 10(b) are diagrams illustrating an example of a method for determining the course of a candidate preceding vehicle. [Figure 6] 4 is a flowchart of a preceding vehicle determination method according to an embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the drawings are schematic and may differ from the actual product. Furthermore, the embodiments of the present invention shown below are examples of devices and methods for embodying the technical concept of the present invention, and the technical concept of the present invention does not limit the structure, arrangement, etc. of component parts to those described below. The technical concept of the present invention can be modified in various ways within the technical scope defined by the claims.

[0009] (composition) The host vehicle 1 is equipped with a cruise control device 10 that supports the driving of the host vehicle 1. The cruise control device 10 detects the driving environment around the host vehicle 1 and automatically controls the driving of the host vehicle 1 based on the detected driving environment, thereby supporting the driving of the host vehicle 1. The cruise control device 10 is an example of a "preceding vehicle determination device" as set forth in the claims. For example, the driving assistance of the host vehicle 1 by the driving control device 10 may include autonomous driving control in which the host vehicle 1 is automatically driven without the involvement of an occupant (e.g., a driver). Also, for example, the driving assistance of the host vehicle 1 by the driving control device 10 may include automatic control of at least one of the driving force, braking force, or steering angle of the host vehicle 1.

[0010] The cruise control device 10 includes a positioning device 11, a map database 12, an external sensor 14, a vehicle sensor 15, a controller 16, and an actuator 17. In the drawings, the map database is referred to as a "map DB." The positioning device 11 measures the current position of the vehicle 1. In the following description, the current position of the vehicle 1 is referred to as "vehicle position." The positioning device 11 may include, for example, a Global Positioning System (GNSS) receiver. The GNSS receiver is, for example, a Global Positioning System (GPS) receiver, and receives radio waves from multiple navigation satellites to measure the vehicle position.

[0011] Map information is stored in the map database 12. The map information stored in the map database 12 may be, for example, map data for navigation that includes information on a road-by-road basis. The map data for navigation may be data that expresses road shapes on a road-by-road basis using a node string. In this specification, a node string may be, for example, an array of multiple nodes, or data that includes an array of multiple nodes and line segments that connect these nodes with curves or straight lines. In other words, a node string represents an array of multiple nodes, i.e., the shape of a road on a map, and is not limited to an array of multiple nodes as long as it includes an array of multiple nodes.

[0012] The external sensor 14 detects various information (driving environment information) about the driving environment around the vehicle 1. For example, the external sensor 14 detects objects around the vehicle 1. The external sensor 14 detects the environment around the vehicle 1, such as objects present around the vehicle 1, the relative position between the vehicle 1 and the object, the distance between the vehicle 1 and the object, and the direction in which the object exists. The external sensor 14 outputs the detected information about the driving environment to the controller 16 as driving environment information. For example, the external sensor 14 detects the relative positions of other vehicles and targets around the vehicle 1 relative to the vehicle 1. Here, targets include, for example, traffic lights provided on the road on which the vehicle 1 is traveling, lines on the road surface (stop lines, lane boundaries, lane markings, etc.), curbs on the shoulders of the road, guardrails, etc.

[0013] The external sensor 14 may include a monocular camera such as a full HD color camera. The camera captures an image including a recognition target in the environment surrounding the vehicle 1, and outputs the captured image to the controller 16 as driving environment information. The external sensor 14 may also include a distance measuring device such as a laser range finder (LRF), radar, or a laser radar such as LiDAR (Light Detection and Ranging). The distance measuring device detects the relative position of the vehicle, which is determined by the relative distance and direction to an object present around the vehicle. The distance measuring device outputs the detected distance data to the controller 16 as driving environment information.

[0014] The vehicle sensor 15 detects various information (vehicle information) obtained from the host vehicle 1. The vehicle sensor 15 includes, for example, a vehicle speed sensor that detects the traveling speed (vehicle speed) of the host vehicle 1, a wheel speed sensor that detects the rotational speed of each tire equipped on the host vehicle 1, a three-axis acceleration sensor (G sensor) that detects the acceleration (including deceleration) in three axial directions of the host vehicle 1, a steering angle sensor that detects the steering angle of the steering wheel, a turning angle sensor that detects the turning angle of the steered wheels, a gyro sensor that detects the angular velocity generated in the host vehicle 1, a yaw rate sensor that detects the yaw rate, an accelerator sensor that detects the amount of operation of the accelerator pedal of the host vehicle 1, and a brake sensor that detects the amount of brake operation by the driver.

[0015] The controller 16 is an electronic control unit (ECU) that controls the driving of the host vehicle 1. When controlling the driving of the host vehicle 1, the controller 16 automatically controls the driving of the host vehicle 1 based on the surrounding driving environment. The controller 16 may be configured as a single electronic control unit or as a collection of multiple electronic control units. The controller 16 includes a processor 20 and peripheral components such as a storage device 21. The processor 20 may be, for example, a CPU (Central Processing Unit) or an MPU (Micro-Processing Unit). The storage device 21 may include a semiconductor storage device, a magnetic storage device, an optical storage device, etc. The storage device 21 may include memories such as a register, a cache memory, a ROM (Read Only Memory) used as a main memory device, and a RAM (Random Access Memory). The functions of the controller 16 described below are realized by, for example, the processor 20 executing a computer program stored in the storage device 21 .

[0016] The controller 16 may be formed of dedicated hardware for executing the information processing described below. For example, the controller 16 may include a functional logic circuit configured in a general-purpose semiconductor integrated circuit. For example, the controller 16 may include a programmable logic device (PLD) such as a field-programmable gate array (FPGA).

[0017] The actuator 17 operates the accelerator opening and braking device of the host vehicle 1 in response to a control signal from the controller 16 to generate a driving force for driving the host vehicle 1 or a braking force for braking the host vehicle 1. The actuator 17 includes an accelerator opening actuator and a brake control actuator. The accelerator opening actuator controls the accelerator opening of the host vehicle 1. The brake control actuator controls the braking operation of the braking device of the host vehicle 1. The actuator 17 may also include a steering actuator that controls the steering direction and steering amount of the steering mechanism of the host vehicle 1. The actuator 17 may operate the steering mechanism of the host vehicle 1 in response to a control signal from the controller 16.

[0018] Next, the driving control of the host vehicle 1 by the controller 16 will be described. The driving control by the controller 16 may include control of the vehicle behavior of the host vehicle 1 based on the relative positional relationship between the host vehicle 1 and a preceding vehicle traveling ahead of the host vehicle 1. For example, the driving control by the controller 16 may include speed control to maintain the inter-vehicle distance between the preceding vehicle and the host vehicle 1 at a set inter-vehicle distance. Furthermore, for example, the driving control by the controller 16 may include control of the steering angle so that the host vehicle 1 travels following the traveling trajectory of the preceding vehicle, or steering angle control to control the steering angle of the host vehicle 1 so that the difference in position between the preceding vehicle and the host vehicle 1 in the lane width direction is reduced.

[0019] The controller 16 determines whether a moving object is a preceding vehicle of the host vehicle based on the degree of deviation in the road width direction between the road shape ahead of the host vehicle 1 and the moving object traveling ahead of the host vehicle 1. For example, if the deviation between the road shape of the host road and the moving object is less than a threshold, the controller 16 may determine that the moving object is a preceding vehicle, and if the deviation is equal to or greater than the threshold, the controller 16 may determine that the moving object is not a preceding vehicle. Also, for example, the probability (likelihood) that the moving object is a preceding vehicle may be calculated so that the smaller the deviation is, the higher it becomes. The controller 16 acquires the road shape of the road on which the vehicle is traveling (hereinafter, may be referred to as the “road shape on which the vehicle is traveling”) from the map data stored in the map database 12.

[0020] Here, the map data stored in the map database 12 is data that expresses road shapes on a road-by-road basis using node strings. 2(a) is a schematic diagram of an example of road shapes acquired from map data. For example, dashed line 30 indicates the road shape of the host road R1, and dashed line 31 indicates the road shape of the oncoming road R2 on which the host vehicle 1 is traveling (hereinafter, sometimes referred to as the "oncoming road shape"). 2(a) shows an example of map data in which the current road shape 30 and the oncoming road shape 31 are each represented by separate node strings. For example, if the current road R1 and the oncoming road R2 are separated by a central reservation, the current road shape 30 and the oncoming road shape 31 are each represented by separate node strings.

[0021] In the case of map data expressed by a row of nodes on a road-by-road basis, each node indicates a position near the center of the road, as shown in Figure 2(a). Therefore, when the number of lanes increases due to the lanes on the road R1 branching into a straight lane Ls and a right-turn lane Lr, such as near the entrance to intersection C, the position of the node in the lane width direction also changes in the direction in which the number of lanes increases (towards the right-turn lane Lr in the example of Figure 2(a)). Therefore, the current road shape 30 represented by the node string may differ from the actual lane shape of the lanes of the current road R1. As a result, if a preceding vehicle is determined based on the road shape of the map data, there is a risk of misidentifying the preceding vehicle.

[0022] For this reason, the present invention focuses on the oncoming road shape 31 of the oncoming road R2. Section S, which is near the entrance to intersection C for the own road R1, is near the exit from intersection C for the oncoming road shape 31. Because the number of lanes in the oncoming road shape 31 does not increase at the exit from intersection C, the oncoming road shape 31 closely matches the shape of the actual lanes of the oncoming road R2. Therefore, the controller 16 translates the shape of the oncoming road so that a point on the shape of the oncoming road that is close to the own vehicle position becomes the own vehicle position.

[0023] 2(b) shows the shape of the oncoming road after the parallel shift. Since the oncoming road shape 31 before the parallel shift closely matches the shape of the actual lane of the oncoming road R2, the oncoming road shape 32 after the parallel shift closely matches the shape of the straight lane Ls of the own road R1, which is parallel to the lane of the oncoming road R2. The controller 16 determines whether the moving object is a preceding vehicle of the vehicle 1 based on the degree of deviation in the road width direction between the oncoming road shape 32 after translation and the moving object. This improves the accuracy of determining a preceding vehicle near the entrance to the intersection C when the vehicle 1 travels straight through the intersection C.

[0024] Next, the driving control device 10 in this embodiment will be described in more detail. Fig. 3 is a block diagram showing an example of the functional configuration of the controller 16 in Fig. 1. The controller 16 functions as a vehicle recognition unit 40, a navigation system 41, a determination unit 42, and a control unit 43. The vehicle recognition unit 40 detects a vehicle traveling ahead of the host vehicle 1 as a preceding vehicle candidate. The vehicle recognition unit 40 includes a preceding vehicle candidate detection unit 40a. The preceding vehicle candidate detection unit 40a detects a vehicle traveling ahead of the host vehicle 1 as a preceding vehicle candidate by analyzing driving environment information detected by the external sensor 14. For example, the vehicle recognition unit 40 may detect a preceding vehicle candidate by analyzing a point cloud captured from a ranging device (e.g., LiDAR) of the external sensor 14. Alternatively, for example, the vehicle recognition unit 40 may detect a preceding vehicle candidate by analyzing an image captured by a camera of the external sensor 14.

[0025] The positioning device 11 is connected to a GNSS antenna installed outside the vehicle cabin, and estimates the current position (vehicle position) and angle (attitude) of the vehicle 1 in a fixed coordinate system of map information stored in the map database 12. Based on the estimated vehicle position, the navigation system 41 identifies the road R1 on which the vehicle 1 is currently traveling from among the roads described in the map data. Furthermore, the navigation system 41 sets a destination through a user operation, searches for a route from the current position to the destination, and stores the route as a planned travel route for the vehicle 1 to travel.

[0026] The navigation system 41 includes an intersection detection unit 41a. Based on map data of the host road R1, the intersection detection unit 41a detects an intersection C where the host road R1 intersects with a cross road within a first predetermined distance ahead of the path of the host vehicle 1. When an intersection is detected, the intersection detection unit 41a extracts the host road shape 30 of the host road R1 and the oncoming road shape 31 of the oncoming road R2 from the map data.

[0027] The determination unit 42 includes a usability determination unit 42a, a preceding vehicle determination unit 42b, and a road shape estimation unit 42c. The usability determination unit 42a determines whether or not the oncoming road shape 31 can be used to determine a preceding vehicle. When determining whether or not the oncoming road shape 31 can be used, the usability determination unit 42a applies the host vehicle road shape 30 and the oncoming road shape 31 to the host vehicle position. Here, fitting the vehicle road shape 30 to the vehicle position means translating the vehicle road shape 30 so that a point on the vehicle road shape 30 near the vehicle position becomes the vehicle position. Similarly, fitting the oncoming road shape 31 to the vehicle position means translating the oncoming road shape 31 so that a point on the oncoming road shape 31 near the vehicle position becomes the vehicle position.

[0028] 4 is a schematic diagram of an example of the host vehicle road shape 33 and the oncoming road shape 32 after translation. For example, the "point on the host vehicle road shape 30 near the host vehicle position" and the "point on the oncoming road shape 31 near the host vehicle position" may be the nearest points on the host vehicle road shape 30 and the oncoming road shape 31 that are located closest to the host vehicle position, respectively. They may also be the feet of perpendicular lines dropped from the host vehicle position to the host vehicle road shape 30 and the oncoming road shape 31, respectively.

[0029] The usability determination unit 42a compares the host vehicle road shape 33 after the parallel movement with the oncoming road shape 32, and if the oncoming road shape 32 deviates from the host vehicle road shape 33 at a second predetermined distance before the intersection to the opposite side (i.e., to the left in the direction of travel) of the oncoming road shape 31 before the parallel movement, the usability determination unit 42a determines that the oncoming road shape 31 is highly correlated with the shape of the straight lane Ls at the intersection C ahead of the host vehicle 1, and determines that the oncoming road shape 31 can be used to determine a preceding vehicle. Note that the second predetermined distance may be equal to or different from the first predetermined distance. For example, the second predetermined distance may be shorter than the first predetermined distance. If the oncoming road shape 32 does not deviate from the oncoming road shape 31 before the parallel movement relative to the own vehicle road shape 33 on the opposite side, the road shape near intersection C differs from the expected shape, so it is not determined that the oncoming road shape 31 can be used to determine the preceding vehicle (or it is determined that it cannot be used).

[0030] The processing of the availability determination unit 42a will be explained in more detail with reference to Figures 2(a) and 2(b). Figures 2(a) and 2(b) show a state in which the vehicle 1 is passing through an intersection C from left to right on the paper. At this time, the navigation system 41 identifies the road shape 30 of the vehicle and the shape 31 of the oncoming road. As described above, the availability determination unit 42a applies (horizontally moves) the current vehicle road shape 30 and the oncoming road shape 31 to the current vehicle position. Fig. 2(b) shows the current vehicle road shape 33 and the oncoming road shape 32 after they have been applied to the current vehicle position (i.e., after translation).

[0031] The usability determination unit 42a determines whether the oncoming road shape 32 deviates from the oncoming road R2 in the opposite direction, that is, upward on the paper, with respect to the host vehicle road shape 33. In the example of FIG. 2(b), the oncoming road shape 32 deviates from the host vehicle road shape 33 in the upward direction on the paper, so the usability determination unit 42a determines that the oncoming road shape 32 can be used to determine a preceding vehicle. 4 is a diagram showing an example of a method for calculating the deviation between the host road shape 33 after parallel movement and the oncoming road shape 32. As shown in FIG. 4, the X axis of the vehicle coordinate system is set to face forward, and the Y axis is set to face left.

[0032] For example, the usability determination unit 42a may calculate the deviation in the Y-axis direction between the host road shape 33 and the oncoming road shape 32 at predetermined intervals along the X-axis and average these deviations to calculate the average deviation amount. The usability determination unit 42a may compare the average deviation amount with a predetermined threshold value to determine whether or not there is a deviation. It should be noted that the determination of the preceding vehicle based on the oncoming road shape 32 can be performed in the area up to the intersection C, so the section for determining the deviation in the Y-axis direction can be the area 34 (shaded in FIG. 4) from the vehicle position to approximately the center of the intersection C (which may be the intersection of roads on the map).

[0033] 3, if the availability determination unit 42a determines that the oncoming road shape 32 is usable, the preceding vehicle determination unit 42b determines whether the candidate preceding vehicle is closer to the oncoming road shape 32 after translation or the host vehicle road shape 33 after translation. When the preceding vehicle candidate is closer to the host vehicle road shape 33, the preceding vehicle determination unit 42b determines that the preceding vehicle candidate is a right-turning vehicle that will turn right at intersection C. When the preceding vehicle candidate is closer to the oncoming road shape 32, the preceding vehicle determination unit 42b determines that the preceding vehicle candidate is a straight-moving vehicle that will go straight through intersection C.

[0034] The operation of the preceding vehicle determination unit 42b will be described with reference to Figures 5(a) and 5(b). First, the preceding vehicle determination unit 42b applies the host vehicle road shape 30 and the oncoming road shape 31 read from the map data to the host vehicle position. Figure 5(a) shows the host vehicle road shape 33 and the oncoming road shape 32 after they have been applied to the host vehicle position (i.e., after translation). Next, the preceding vehicle determination unit 42b calculates the deviation amount τ1 between the preceding vehicle candidate 2 and the own vehicle road shape 33 and the oncoming road shape 32 after parallel movement, and the deviation amount τ2 between the preceding vehicle candidate 2 and the oncoming road shape 32.

[0035] When the deviation amount τ1 is greater than the deviation amount τ2 as shown in FIG. 5(a), the preceding vehicle determination unit 42b determines that the candidate preceding vehicle 2 is a straight-moving vehicle. When the deviation amount τ2 is greater than the deviation amount τ1 as shown in FIG. 5(b), the preceding vehicle determination unit 42b determines that the candidate preceding vehicle 2 is a right-turning preceding vehicle. Note that when the deviation amounts τ2 and τ1 are equal, the preceding vehicle determination unit 42b does not need to determine whether the candidate preceding vehicle 2 is a straight-moving vehicle or a right-turning preceding vehicle. In this case, the road shape estimation unit 42c, which will be described later, does not need to determine whether the candidate preceding vehicle 2 is a leading vehicle. Alternatively, the candidate preceding vehicle 2 may be determined to not be a leading vehicle.

[0036] See Fig. 3. The road shape estimation unit 42c acquires the planned driving route of the host vehicle 1 from the navigation system 41. The road shape estimation unit 42c determines whether or not the traveling direction of the candidate preceding vehicle 2 at the intersection C matches the path that the host vehicle 1 will take through the intersection C along the planned driving route set by the navigation system 41 (hereinafter referred to as the "planned driving route"). When the traveling direction of the candidate preceding vehicle 2 matches the planned driving path, the road shape estimation unit 42c determines that the candidate preceding vehicle 2 is a preceding vehicle. In this case, the road shape estimation unit 42c calculates the driving trajectory of the preceding vehicle, and estimates and sets the shape of the calculated driving trajectory as the shape of the road on which the host vehicle 1 should travel (i.e., the road shape of the host vehicle road).

[0037] For example, the roadway shape estimation unit 42c may calculate a curve obtained by polynomial approximation of the positions of the preceding vehicle detected at discrete times (for example, an approximate curve of a cubic function) as the traveling trajectory of the preceding vehicle. The control unit 43 drives the actuator 17 to control the accelerator and brake, as well as the steering direction and steering amount of the steering mechanism, so that the host vehicle 1 travels following the preceding vehicle. For example, the accelerator and brake are controlled to maintain a set distance between the preceding vehicle and the host vehicle 1. Also, for example, the steering direction and steering amount of the steering mechanism are controlled so that the host vehicle 1 travels along a road shape set based on the travel trajectory of the preceding vehicle.

[0038] (operation) FIG. 6 is a flowchart of a preceding vehicle determination method according to the embodiment. In step S1, the positioning device 11 detects the current position of the vehicle 1 (the vehicle position). In step S2, the preceding vehicle candidate detection unit 40a detects a vehicle traveling ahead of the host vehicle 1 as a preceding vehicle candidate. In step S3, the intersection detection unit 41a determines whether or not there is an intersection C where the host road R1 intersects with a cross road ahead of the host vehicle 1. If there is an intersection C (step S3: Y), the process proceeds to step S4. If there is no intersection C (step S3: N), the process ends.

[0039] In step S4, the intersection detection unit 41a extracts the current road shape 30 of the current road R1 and the opposite road shape 31 of the opposite road R2 from the map data. In step S5, the determination unit 42 translates the host road shape 30 so that a point on the host road shape 30 that is near the host vehicle position becomes the host vehicle position. Similarly, the determination unit 42 translates the oncoming road shape 31 so that a point on the oncoming road shape 31 that is near the host vehicle position becomes the host vehicle position.

[0040] In step S6, the usability determination unit 42a determines whether the oncoming road shape 31 can be used to determine a preceding vehicle by comparing the host vehicle road shape 33 after parallel movement with the oncoming road shape 32. If the oncoming road shape 31 can be used (step S6: Y), the process proceeds to step S7. If the oncoming road shape 31 cannot be used (step S6: N), the process ends.

[0041] In step S7, the preceding vehicle determination unit 42b calculates the amount of deviation τ1 between the preceding vehicle candidate and the road shape 33 for the current vehicle. In step S8, the preceding vehicle determination unit 42b calculates the amount of deviation τ2 between the preceding vehicle candidate and the oncoming road shape 32. In step S9, the preceding vehicle determination unit 42b determines whether the deviation amount τ1 is greater than the deviation amount τ2. If the deviation amount τ1 is greater than the deviation amount τ2 (step S9: Y), the process proceeds to step S10. If the deviation amount τ2 is greater than the deviation amount τ1 (step S9: N), the process proceeds to step S11.

[0042] In step S10, the preceding vehicle determination unit 42b determines that the preceding vehicle candidate is a vehicle traveling straight through the intersection C. Thereafter, the process proceeds to step S12. In step S11, the preceding vehicle determination unit 42b determines that the preceding vehicle candidate is a right-turning vehicle that will turn right at the intersection C. Thereafter, the process proceeds to step S12. In step S12, the roadway shape estimation unit 42c determines whether the traveling direction of the candidate preceding vehicle matches the planned traveling path of the host vehicle 1. If the traveling direction of the candidate preceding vehicle matches the planned traveling path of the host vehicle 1 (step S12: Y), the process proceeds to step S13. If the traveling direction of the candidate preceding vehicle does not match the planned traveling path of the host vehicle 1 (step S12: N), the process proceeds to step S15.

[0043] In step S13, the road shape estimation unit 42c determines that the preceding vehicle candidate is a preceding vehicle of the host vehicle 1. In step S14, the road shape estimation unit 42c calculates the travel path of the preceding vehicle, and estimates and sets the shape of the calculated travel path as the shape of the road on which the host vehicle 1 should travel. Then, the process ends. In step S15, the road shape estimation unit 42c determines that the preceding vehicle candidate is not a preceding vehicle of the host vehicle 1. Then, the process ends.

[0044] (Effects of the embodiment) (1) Positioning device 11 detects the host vehicle position, which is the current position of host vehicle 1. External sensor 14 detects a moving object ahead of host vehicle 1 that is moving in the same direction as the traveling direction of host vehicle 1. Controller 16 detects whether an intersection exists within a first predetermined distance ahead of host vehicle 1 based on map data in which road shapes are expressed on a road-by-road basis using an arrangement of multiple nodes and the host vehicle position. If controller 16 detects that an intersection exists within the first predetermined distance ahead of host vehicle 1, it extracts from the map data the shape of the oncoming road on which an oncoming vehicle is traveling, translates the shape of the oncoming road so that a point on the shape of the oncoming road near the host vehicle position becomes the host vehicle position, and determines whether the moving object is a preceding vehicle of host vehicle 1 based on the degree of deviation in the road width direction between the moving object and the shape of the oncoming road after translation. In this way, whether or not a moving object is a preceding vehicle is determined based on the shape of the oncoming road that more closely matches the actual road shape, so when the vehicle 1 goes straight through an intersection, it is possible to avoid erroneously setting a vehicle ahead that has entered a right-turn lane as a preceding vehicle.

[0045] (2) The controller 16 extracts the host road shape, which is the road shape of the host road on which the host vehicle 1 is traveling, from the map data, translates the host road shape so that a point on the host road shape near the host vehicle position becomes the host vehicle position, translates the oncoming road shape so that a point on the oncoming road shape near the host vehicle position becomes the host vehicle position, and determines whether the moving object is a vehicle preceding the host vehicle 1 if the oncoming road shape after the translation deviates from the host road shape after the translation to the opposite side of the oncoming road before the translation at a point a second predetermined distance before the intersection, and does not need to determine whether the moving object is a vehicle preceding the host vehicle 1 if the oncoming road shape after the translation does not deviate from the host road shape after the translation to the opposite side of the oncoming road before the translation. In this way, by comparing the shape of the oncoming road with the shape of the road on which the vehicle is traveling, and confirming that the shape of the oncoming road deviates to the left of the road in the direction of travel compared to the shape of the road on which the vehicle is traveling, which often deviates to the right of the actual road shape, it can be determined that the shape of the road on which the vehicle is traveling is more consistent with the actual road shape than the shape of the road on which the vehicle is traveling.

[0046] (3) The controller 16 extracts the host road shape, which is the road shape of the host road on which the host vehicle 1 is traveling, from the map data, translates the host road shape so that a point on the host road shape near the host vehicle position becomes the host vehicle position, translates the oncoming road shape so that a point on the oncoming road shape near the host vehicle position becomes the host vehicle position, determines that the moving object's path is a right turn if the degree of deviation in the road width direction between the moving object and the host road shape after parallel translation is smaller than the degree of deviation in the road width direction between the moving object and the oncoming road shape after parallel translation, determines that the moving object's path is a straight path if the degree of deviation in the road width direction between the moving object and the oncoming road shape after parallel translation is smaller than the degree of deviation in the road width direction between the moving object and the host road shape after parallel translation, and may determine that the moving object is a preceding vehicle of the host vehicle 1 if the planned driving path of the host vehicle 1 matches the path of the moving object. In this way, a preceding vehicle along the planned driving path of the vehicle 1 is selected depending on whether the moving object is closer to the shape of the oncoming road or the shape of the road on which the vehicle is traveling, so the preceding vehicle can be correctly determined whether the vehicle 1 is going straight through the intersection or turning right.

[0047] (4) The controller 16 may estimate that the travel path of a moving object determined to be a preceding vehicle of the host vehicle 1 is the road shape of the host vehicle road. In this way, the road shape is estimated based on the travel trajectory of the preceding vehicle along the planned travel route of the vehicle itself, so even if road signs are laid out in a complex manner before an intersection, the road can be estimated without being confused by the road signs. [Explanation of symbols]

[0048] 1...Own vehicle, 10...cruising control device, 11...positioning device, 12...map database, 14...external sensor, 15...vehicle sensor, 16...controller, 17...actuator, 20...processor, 21...storage device, 40...vehicle recognition unit, 40a...preceding vehicle candidate detection unit, 41...navigation system, 41a...intersection detection unit, 42...determination unit, 42a...usability determination unit, 42b...preceding vehicle determination unit, 42c...roadway shape estimation unit, 43...control unit

Claims

1. Detecting the current location of the vehicle; detecting a moving object in front of the host vehicle and moving in the same direction as the host vehicle's traveling direction; detecting whether or not an intersection exists within a first predetermined distance ahead of the vehicle based on map data in which road shapes are expressed on a road-by-road basis using an array of multiple nodes indicating positions near the center of the road, and the vehicle position; extracting, from the map data, an oncoming road shape that is a road shape of an oncoming road on which an oncoming vehicle of the host vehicle is traveling, when detecting that an intersection through which the host vehicle is traveling is present within the first predetermined distance ahead of the host vehicle; translating the shape of the oncoming road so that a point on the shape of the oncoming road that is in the vicinity of the vehicle position becomes the vehicle position; determining whether the moving object is a preceding vehicle of the host vehicle within a range from the host vehicle position to the intersection based on a degree of deviation in a road width direction between the moving object and the shape of the oncoming road after translation; A method for determining a preceding vehicle.

2. extracting from the map data a road shape of a road on which the vehicle is traveling; translating the vehicle road shape so that a point on the vehicle road shape that is in the vicinity of the vehicle position becomes the vehicle position; translating the shape of the oncoming road so that a point on the shape of the oncoming road that is in the vicinity of the vehicle position becomes the vehicle position; If, at a point a second predetermined distance before the intersection, the shape of the oncoming road after the parallel movement deviates from the shape of the own vehicle road after the parallel movement to the side opposite the oncoming road before the parallel movement, it is determined whether or not the moving object is a preceding vehicle of the own vehicle, and if the shape of the oncoming road after the parallel movement does not deviate from the shape of the own vehicle road after the parallel movement to the side opposite the oncoming road before the parallel movement, it is not determined whether or not the moving object is a preceding vehicle of the own vehicle.

2. The method for determining a preceding vehicle according to claim 1.

3. extracting from the map data a road shape of a road on which the vehicle is traveling; translating the vehicle road shape so that a point on the vehicle road shape that is in the vicinity of the vehicle position becomes the vehicle position; translating the shape of the oncoming road so that a point on the shape of the oncoming road that is in the vicinity of the vehicle position becomes the vehicle position; determining that the course of the moving object is turning right when the degree of deviation in the road width direction from the shape of the road on which the moving object is traveling after translation is smaller than the degree of deviation in the road width direction from the shape of the oncoming road on which the moving object is traveling after translation, determining that the path of the moving object is moving straight when the degree of deviation in the road width direction between the shape of the oncoming road after the moving object has moved parallel to the road and the oncoming road shape is smaller than the degree of deviation in the road width direction between the moving object and the shape of the own road after the moving object has moved parallel to the road; When the planned traveling path of the host vehicle coincides with the path of the moving object, the moving object is determined to be a preceding vehicle of the host vehicle.

2. The method for determining a preceding vehicle according to claim 1.

4. A preceding vehicle determination method according to any one of claims 1 to 3, characterized in that the traveling trajectory of the moving object determined to be a preceding vehicle of the subject vehicle is estimated to be the road shape of the subject road on which the subject vehicle is traveling.

5. a positioning device that detects a vehicle position, which is the current position of the vehicle; a sensor that detects objects around the vehicle; and a controller; The controller detecting a moving object in front of the host vehicle and moving in the same direction as the host vehicle's traveling direction based on the output of the sensor; detecting whether or not an intersection exists within a first predetermined distance ahead of the vehicle based on map data in which road shapes are expressed on a road-by-road basis using an array of multiple nodes indicating positions near the center of the road, and the vehicle position; extracting, from the map data, an oncoming road shape that is a road shape of an oncoming road on which an oncoming vehicle of the host vehicle is traveling, when detecting that an intersection through which the host vehicle is traveling is present within the first predetermined distance ahead of the host vehicle; translating the shape of the oncoming road so that a point on the shape of the oncoming road that is in the vicinity of the vehicle position becomes the vehicle position; determining whether the moving object is a preceding vehicle of the host vehicle within a range from the host vehicle position to the intersection based on a degree of deviation in a road width direction between the moving object and the shape of the oncoming road after translation; A preceding vehicle determination device.

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