Control device, warning control method and program

Abstract

To provide a control device, a warning control method, and a program that can issue a warning when danger is predicted.SOLUTION: A control device according to the present disclosure issues a warning about another vehicle approaching an own vehicle, and includes a first detection unit, a second detection unit, and an output control unit. The first detection unit detects the position of a lane boundary line, which indicates the width boundary of a road where the vehicle is traveling, based on an image captured by an image capturing unit that captures images of the vehicle's surroundings. The second detection unit detects the position of another vehicle based on the captured image. The output control unit controls the output of warnings to a driver of the own vehicle based on the relationship between the position of the lane boundary line detected by the first detection unit and the position of the other vehicles detected by the second detection unit.SELECTED DRAWING: Figure 6

Description

[Technical field]

[0001] The present disclosure relates to a control device, a warning control method, and a program. [Background technology]

[0002] A function that warns of the approach of other vehicles is useful for preventing accidents. For example, an approach warning function that flashes a part of the side mirror has been put to practical use. As a technology for issuing such a warning, for example, a technology has been disclosed that has a radar having a first detection area that detects an object traveling on the rear side of the vehicle and a second detection area that is narrower in the vehicle width direction than the first detection area, a detector that detects the traveling state, and a controller that switches between the first detection area and the second detection area and controls the radar according to the traveling state other than the traveling direction when the traveling direction of the traveling state is straight ahead (for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2017 / 082370 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in conventional technology, when an approaching vehicle is detected, a warning is always issued even when no particular danger is predicted, and the driver's awareness of danger is reduced as warnings for vehicles that enter the detection range become a regular occurrence. In order to suppress this, it is possible to narrow the detection area of ​​the radar. This reduces the number of times warnings are issued, but narrows the detection area. In addition, since the detection means is radar, it is difficult to establish a complex detection logic. As a result of the above, there is a problem of reduced accuracy in danger prediction.

[0005] An object of the present disclosure is to provide a control device, a warning control method, and a program that can issue a warning when danger is predicted. [Means for solving the problem]

[0006] A control device according to the present disclosure includes a first detection unit, a second detection unit, a first acquisition unit, a second acquisition unit, a first determination unit, and a third determination unit; and an output control unit. The first detection unit detects the position of a lane boundary line indicating a boundary in a width direction of the road on which the vehicle is traveling based on an image captured by an imaging unit that captures an image of the surroundings of the vehicle. The second detection unit detects the position of another vehicle based on the captured image. The first acquisition unit acquires lane position information indicating the position of the lane boundary line detected by the first detection unit. The second acquisition unit acquires position information indicating the position of the other vehicle detected by the second detection unit, distance information of the other vehicle based on the position of the other vehicle, and absolute speed information of the host vehicle from the vehicle speed detection unit. The first determination unit performs a driving state determination as to whether the other vehicle and the host vehicle are traveling in the same lane or are about to enter a state in which they will travel in the same lane, based on the lane position information acquired by the first acquisition unit and the position information acquired by the second acquisition unit. When the first determination unit determines that the other vehicle and the host vehicle are traveling in the same lane or are about to enter a state in which they will travel in the same lane, the third determination unit changes the predetermined distance range according to the absolute speed information, and determines whether the distance between the other vehicle and the host vehicle is within the changed distance range based on the distance information. The output control unit When the third determination unit determines that the distance between the other vehicle and the host vehicle is within the distance range, The system performs control to output a warning to the driver of the vehicle.

[0007] Further, the warning control method according to the present disclosure includes a first detection step, a second detection step, A first acquisition step, a second acquisition step, a first determination step, and a third determination step. and an output control step. The first detection step detects the position of a lane boundary line indicating a boundary in a width direction of a road on which the vehicle is traveling based on an image captured by an imaging unit that captures an image of the surroundings of the vehicle. The second detection step detects the position of another vehicle based on the captured image. The first acquisition step acquires lane position information indicating the position of the lane boundary line detected by the first detection step. The second acquisition step acquires position information indicating the position of the other vehicle detected by the second detection step, distance information of the other vehicle based on the position of the other vehicle, and absolute speed information of the host vehicle from the vehicle speed detection unit. The first determination step performs a driving state determination as to whether the other vehicle and the host vehicle are traveling in the same lane or whether the other vehicle and the host vehicle are about to travel in the same lane, based on the lane position information acquired by the first acquisition step and the position information acquired by the second acquisition step. The third determination step changes a predetermined distance range according to the absolute speed information when it is determined by the first determination step that the other vehicle and the host vehicle are traveling in the same lane, or when it is determined that the other vehicle and the host vehicle are about to travel in the same lane, and determines whether the distance between the other vehicle and the host vehicle is within the changed distance range based on the distance information. The output control step is When it is determined in the third determination step that the distance between the other vehicle and the host vehicle is within the distance range, The system performs control to output a warning to the driver of the vehicle.

[0008] Further, the program according to the present disclosure includes a first detection step, a second detection step, and A first acquisition step, a second acquisition step, a first determination step, and a third determination step. and an output control step. The first detection step detects the position of a lane boundary line indicating a boundary in a width direction of the road on which the vehicle is traveling based on an image captured by an imaging unit that captures an image of the surroundings of the vehicle. The second detection step detects the position of another vehicle based on the captured image. The first acquisition step acquires lane position information indicating the position of the lane boundary line detected by the first detection step. The second acquisition step acquires position information indicating the position of the other vehicle detected by the second detection step, distance information of the other vehicle based on the position of the other vehicle, and absolute speed information of the host vehicle from the vehicle speed detection unit. The first determination step performs a driving state determination as to whether the other vehicle and the host vehicle are traveling in the same lane or whether the other vehicle and the host vehicle are about to travel in the same lane, based on the lane position information acquired by the first acquisition step and the position information acquired by the second acquisition step. The third determination step changes a predetermined distance range according to the absolute speed information when it is determined by the first determination step that the other vehicle and the host vehicle are traveling in the same lane, or when it is determined that the other vehicle and the host vehicle are about to travel in the same lane, and determines whether the distance between the other vehicle and the host vehicle is within the changed distance range based on the distance information. The output control step is When it is determined in the third determination step that the distance between the other vehicle and the host vehicle is within the distance range, The system performs control to output a warning to the driver of the vehicle. Effect of the Invention

[0009] According to the control device, warning control method, and program of the present disclosure, a warning can be issued when danger is predicted. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1 is a diagram showing an example of an overall configuration of a vehicle according to an embodiment. [Diagram 2] FIG. 2 is a diagram for explaining an outline of a warning operation in the vehicle according to the embodiment. [Diagram 3] FIG. 3 is a diagram illustrating a problem that may arise when the vehicle detection range is narrow. [Figure 4] FIG. 4 is a diagram illustrating a problem that may arise when the vehicle detection range is narrow. [Diagram 5] FIG. 5 is a diagram illustrating an example of a hardware configuration of the vehicle control device according to the embodiment. [Figure 6] FIG. 6 is a diagram illustrating an example of a functional block configuration of the vehicle control device according to the embodiment. [Figure 7] FIG. 7 is a diagram showing an example of a pattern for issuing a warning in the vehicle control device according to the embodiment. [Figure 8] FIG. 8 is a diagram showing an example of a pattern in which a warning is not issued in the vehicle control device according to the embodiment. [Figure 9] FIG. 9 is a diagram for explaining that in the vehicle according to the embodiment, a warning is not required when another vehicle is moving away. [Figure 10] FIG. 10 is a diagram for explaining the operation of changing the timing of issuing a warning depending on the absolute speed of another vehicle in the vehicle according to the embodiment. [Figure 11] FIG. 11 is a diagram showing an example of the flow of the vehicle approach warning process of the vehicle control device according to the embodiment. [Figure 12] FIG. 12 is a diagram illustrating an example of a flow of a vehicle approach detection process of the vehicle control device according to the embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, embodiments of a control device, a warning control method, and a program according to the present disclosure will be described with reference to the drawings.

[0012] (Overall vehicle configuration) Fig. 1 is a diagram showing an example of the overall configuration of a vehicle according to an embodiment of the present invention. The overall configuration of a vehicle 1 according to the present embodiment will be described with reference to Fig. 1.

[0013] As shown in FIG. 1, the vehicle 1 includes a body 2, wheels 3F, and wheels 3R. The wheels 3F are a pair of front wheels that are installed on the front side of the body 2 and contact the road surface. The wheels 3R ​​are a pair of rear wheels that are installed on the rear side of the body 2 and contact the road surface. The vehicle 1 can run using a pair of wheels 3F and a pair of wheels 3R ​​that are arranged along a predetermined direction. In this case, the predetermined direction in which the wheels 3F and the wheels 3R ​​are arranged becomes the direction of movement of the vehicle 1, and the vehicle 1 can move forward or backward by switching gears, etc. Note that when referring to any of the wheels 3F and the wheels 3R, or when referring to them collectively, they will simply be referred to as "wheels 3".

[0014] As shown in FIG. 1, the vehicle 1 is equipped with a seat 4, a vehicle drive unit 5, an imaging unit 6a, an imaging unit 6b, a door mirror 7L, a door mirror 7R, a rear seat 8, a rearview mirror 9, an engine switch 10, a steering wheel 11, a shift lever 12, a parking brake 13, a door lock device 14, a display device 15, and a vehicle control device 20.

[0015] The seat 4 is provided in the vehicle cabin of the vehicle 1 and serves as a driver's seat for the driver of the vehicle 1. While seated in the seat 4, the driver can steer the vehicle 1 by operating the steering wheel 11 and an accelerator pedal and a brake pedal (not shown).

[0016] The vehicle drive unit 5 is a drive device mounted on the vehicle 1. The vehicle drive unit 5 is, for example, an engine, a motor, a drive unit for the wheels 3, or the like.

[0017] The imaging unit 6a is a camera provided in the front part of the vehicle 1, which captures an image of the front of the vehicle 1. The imaging unit 6b is a camera provided in the rear part of the vehicle 1, which captures an image of the rear of the vehicle 1. As described later, the imaging units 6a and 6b are assumed to be monocular cameras or stereo cameras capable of detecting the position, distance, speed, etc. of other vehicles. When referring to any imaging unit among the imaging units 6a and 6b, or when referring to them collectively, they are simply referred to as the "imaging unit 6". The imaging units 6a and 6b may be provided in the door mirror 7L and the door mirror 7R. This makes it possible to output a warning for an approaching vehicle from the side that is not detected by the front camera and the rear camera, for example.

[0018] The door mirror 7L is an exterior rear-view mirror attached to the front of the left door of the vehicle body 2 for viewing the left rear. The rear-view mirror 7R is an exterior rear-view mirror attached to the front of the right door of the vehicle body 2 for viewing the right rear. The door mirror 7L and the door mirror 7R each have an indicator light built in to warn of the approach of another vehicle. Note that when referring to any door mirror among the door mirror 7L and the door mirror 7R, or when referring to them collectively, they will be simply referred to as "door mirror 7". The door mirror may also be referred to as a side mirror, etc. In addition, instead of the door mirror 7, a fender mirror attached to the front end of the hood of the vehicle body 2 may be installed.

[0019] The rear seat 8 is provided at the rear side of the passenger compartment of the vehicle 1, and is a seat for passengers other than the driver of the vehicle 1 to sit in.

[0020] The room mirror 9 is an interior rear-view mirror that is installed on the ceiling above the windshield and allows the driver to view the rear and rear-side areas. The room mirror 9 is also an electronic inner mirror that displays an image of the rear view captured by a camera installed on the top of the rear window, for example. The room mirror 9 also has a function of displaying a warning of the approach of other vehicles. The room mirror is also called a back mirror.

[0021] The engine switch 10 is a switch that the driver operates when starting the engine of the vehicle 1. The engine switch 10 is also called an ignition switch. The driver operates the engine switch 10 to start or stop the engine of the vehicle 1. The operation of the engine switch 10 also controls the power supply to electronic devices mounted on the vehicle 1.

[0022] The steering wheel 11 is a steering wheel for steering the vehicle 1 and is installed on the dashboard in front of the seat 4.

[0023] The shift lever 12 is a lever that the driver operates when changing the shift position. The movable range of the shift lever 12 includes, for example, a parking position, a reverse position, a neutral position, and a drive position. When the shift lever 12 is in the parking position, the vehicle 1 is in a so-called parked state in which the power of the engine is not transmitted to the wheels 3. When the shift lever 12 is in the reverse position, the vehicle 1 is in a state in which it can move backward. When the shift lever 12 is in the drive position, the vehicle 1 is in a state in which it can move forward.

[0024] The parking brake 13 is one of the brake mechanisms of the vehicle 1. The parking brake 13 is a manual braking mechanism that allows the driver to manually stop the movement of the vehicle 1. When the parking brake 13 is applied, the movement of the vehicle 1 is stopped and the vehicle 1 is in a parked state. When the parking brake 13 is released, the vehicle 1 is in a movable state. The parking brake is also called a side brake.

[0025] The door lock device 14 is a device that switches the state of the doors of the vehicle 1 between a locked state and an unlocked state. For example, the door of the vehicle 1 can be switched between a locked state and an unlocked state by a key for the vehicle 1 or the like from outside the vehicle 1.

[0026] The display device 15 is a display device such as an LCD (Liquid Crystal Display) or an OELD (Organic Electro-Luminescent Display) that is installed on a dashboard or the like in front of the seat 4. The display device 15 has an image display function as well as a voice output function and an input function. The display device 15 also has a function of displaying a warning of the approach of another vehicle.

[0027] The audio output function of the display device 15 may be realized by a speaker 19 shown in Fig. 5 described later. The display device 15 may be configured as a touch panel having an input function for receiving operation input by a user. The display device 15 may also include a navigation device having a location information acquisition function and a route search function using map information.

[0028] The vehicle control device 20 is an ECU (Electronic Control Unit) or an OBU (On Board Unit) that controls various operations of the vehicle 1. The vehicle control device 20 according to this embodiment controls a vehicle approach warning process for detecting and warning the approach of another vehicle to the vehicle 1. Here, the vehicle 1 is an example of the vehicle itself. In this embodiment, a case where another vehicle approaches the vehicle 1 from behind will be described as an example. That is, the vehicle approach warning process using the captured image of the imaging unit 6b that captures the rear of the vehicle 1 will be described. However, this vehicle approach warning process can also be applied to a case where another vehicle approaches the vehicle 1 from the front, that is, mainly a case where the vehicle 1 approaches another vehicle in front. In this case, the vehicle approach warning process is executed using the captured image of the imaging unit 6a that captures the front of the vehicle 1. When the vehicle approach warning process is applied to a case where the vehicle 1 approaches another vehicle in front, for example, when the front of the vehicle 1 is difficult to see due to weather conditions such as dense fog, a warning about the approach of the vehicle in front can be appropriately issued, thereby improving the safety of driving.

[0029] (Overview of vehicle warning operation) 2 is a diagram for explaining an outline of a warning operation in the vehicle according to the embodiment. With reference to FIG. 2, an outline of the warning operation in the vehicle 1 according to the embodiment will be explained.

[0030] In the example shown in FIG. 2(a), the vehicle 1, which is the vehicle itself, is traveling in the lane LN1 on the right side of the lane boundary line L. In other words, the lane LN1 is the vehicle itself lane. Meanwhile, the other vehicle 30, which is the other vehicle other than the vehicle 1, is traveling in the lane LN2 on the left side of the lane boundary line L. In this case, the lane LN2 is the other lane compared to the lane LN1, which is the vehicle itself lane on which the vehicle 1 is traveling. Even if the other vehicle 30 approaches the vehicle 1 and enters the vehicle detection range of the vehicle 1, as long as the other vehicle 30 is traveling in the lane LN2, which is the other lane, there is little risk that the other vehicle 30 will collide with or come into contact with the vehicle 1. Therefore, in this case, the vehicle 1 does not issue an approaching vehicle warning to the driver. Here, the vehicle detection range is the angle of view range of the imaging unit 6b that images the rear of the vehicle 1.

[0031] In the example shown in FIG. 2(b), the vehicle 1 is traveling in the lane LN1 on the right side of the lane boundary line L. In other words, the lane LN1 is the vehicle's own lane. Meanwhile, another vehicle 30, which is another vehicle, is also traveling in the lane LN1. In this case, if the other vehicle 30 approaches the vehicle 1 and enters the vehicle detection range of the vehicle 1, there is a risk that the other vehicle 30 will collide with or come into contact with the vehicle 1. Therefore, in this case, the vehicle 1 issues an approaching warning of the other vehicle 30 to the driver.

[0032] In this way, in the vehicle 1 according to this embodiment, the lane boundary line L is detected based on the captured image captured by the imaging unit 6b, the position of the other vehicle 30 is determined, and whether or not a warning is necessary is determined, and a vehicle approach warning process is executed to issue a warning only when a warning is necessary. Details of this vehicle approach warning process will be described later. Note that the lane boundary line L includes not only a boundary line that divides a driving lane or an overtaking lane on a multi-lane road, but also a center line that is a boundary with an oncoming lane, and a boundary line with a roadside strip. Therefore, although a multi-lane road is used as an example for explanation in FIG. 2, the present invention is not limited to this, and the vehicle approach warning process of the vehicle control device 20 according to this embodiment can be applied even to a road with one lane on each side.

[0033] (Issues that may arise when the vehicle detection range is narrow) 3 and 4 are diagrams for explaining problems that may arise when the vehicle detection range is narrow. With reference to FIG. 3 and FIG. 4, problems caused by a narrow detection range in the conventional technology will be explained. Note that, here, the explanation focuses on the angle of view range of an imaging device as an example of the detection range. The angle of view range of an imaging device is also the range captured by the imaging device. The imaging device is, for example, a camera.

[0034] Fig. 3 shows a state in which a mirror image of an image captured by an imaging device installed at the rear of a vehicle is displayed toward the driver. As shown in Fig. 3, the imaging device has an angle of view of, for example, 65°. In this case, the range captured by the imaging device is an area CAR, an area RAR located to the left of the area CAR, and an area LAR located to the right of the area CAR.

[0035] As described above, in order to prevent warnings against vehicles that have entered the detection range from becoming a regular occurrence, a method of narrowing the detection range is conceivable. One example of this is a method of narrowing the angle of view of the imaging device, as shown in FIG. 3. In the example shown in FIG. 3, the angle of view of the imaging device is narrowed to 20°. In this case, the range captured by the imaging device is only the area CAR shown in FIG. 3. Therefore, the vehicle cannot make a risk prediction for objects such as vehicles included in the areas RAR and LAR that are outside the detection range.

[0036] FIG. 4 shows a state in which a mirror image of an image captured by an imaging device installed at the rear of a vehicle is displayed toward the driver. FIG. 4 shows a state in which an object that was included in the area CAR (see FIG. 4(a)) is not included in the area CAR but is included in the area RAR (see FIG. 4(b)) as the host vehicle moves forward. In this case, an imaging device with a field angle of 20° cannot capture the area RAR, and therefore cannot detect the object included in the area RAR. Therefore, when an object that was included in the area CAR is included in the area RAR due to the host vehicle approaching, the host vehicle cannot predict the danger of the object even though the host vehicle has approached the object.

[0037] In order to solve the problems caused by narrowing the angle of view, the vehicle 1 according to this embodiment does not narrow the angle of view of the imaging device (e.g., imaging unit 6b), but instead determines whether or not a warning is necessary, and issues a warning only when necessary.

[0038] (Hardware configuration of vehicle control device) 5 is a diagram showing an example of a hardware configuration of a vehicle control device according to an embodiment. The hardware configuration of the vehicle control device 20 according to the present embodiment will be described with reference to FIG.

[0039] 5, the vehicle control device 20 includes a CPU (Central Processing Unit) 101, a RAM (Random Access Memory) 102, a ROM (Read Only Memory) 103, an imaging I / F 104, a display I / F 105, a GPS (Global Positioning System) I / F 106, a vehicle speed I / F 107, a communication I / F 108, and an audio I / F 109. The CPU 101, the RAM 102, the ROM 103, the imaging I / F 104, the display I / F 105, the GPS I / F 106, the vehicle speed I / F 107, the communication I / F 108, and the audio I / F 109 are connected to one another via a bus 110 so as to enable data communication.

[0040] The CPU 101 is a calculation device that controls the entire vehicle control device 20. The RAM 102 is a volatile storage device that serves as a work area for processing by the CPU 101. The ROM 103 is a non-volatile storage device that stores the control program for the vehicle control device 20, various data, and the like.

[0041] The imaging I / F 104 is an interface for receiving captured images captured by the imaging units 6a and 6b. The imaging I / F 104 continuously receives the captured images captured by the imaging units 6a and 6b as frame images to obtain them as a moving image.

[0042] The display I / F 105 is an interface for displaying various displays such as warning displays by the vehicle approach warning process. For example, the door mirrors 7, the rearview mirror 9, and the display device 15 are connected to the display I / F 105 as shown in FIG.

[0043] The GPS I / F 106 is an interface for receiving position information received by a GPS sensor 16 installed in the vehicle 1. The position information received by the GPS sensor 16 is, for example, a GPS signal. The vehicle speed I / F 107 is an interface for receiving speed information from a vehicle speed sensor 17 that detects the vehicle speed of the vehicle 1. The vehicle speed sensor 17 is, for example, installed near the wheels 3, and is a vehicle speed detection unit that generates a vehicle speed pulse that indicates the rotation speed or number of rotations of the wheels 3. The vehicle speed I / F 107 acquires the vehicle speed pulse generated by the vehicle speed sensor 17, and calculates the traveling speed of the vehicle 1 based on the vehicle speed pulse.

[0044] The communication I / F 108 is an interface for transmitting and receiving data to and from a communication device 18 installed in the vehicle 1. The communication device 18 performs data communication with an external device such as a server via wireless communication. This allows the communication I / F 108 to perform data communication with the external device via the communication device 18.

[0045] The audio I / F 109 is an interface for outputting audio data to a speaker 19 installed in the vehicle 1 .

[0046] It should be noted that the hardware configuration of the vehicle control device 20 shown in FIG. 5 is merely an example, and does not necessarily include all of the components shown in FIG. 2, or may include other components.

[0047] (Configuration and operation of functional blocks of vehicle control device) FIG. 6 is a diagram showing an example of the configuration of functional blocks of the vehicle control device according to the embodiment. FIG. 7 is a diagram showing an example of a pattern in which a warning is issued in the vehicle control device according to the embodiment. FIG. 8 is a diagram showing an example of a pattern in which a warning is not issued in the vehicle control device according to the embodiment. FIG. 9 is a diagram explaining that a warning is not required when another vehicle is moving away in the vehicle according to the embodiment. FIG. 10 is a diagram explaining an operation of changing the timing of issuing a warning according to the absolute speed of the other vehicle in the vehicle according to the embodiment. The configuration and operation of functional blocks of the vehicle control device 20 according to the present embodiment will be described with reference to FIGS. 6 to 10.

[0048] As shown in FIG. 6, the vehicle control device 20 includes a vehicle detection unit 201, a detected vehicle information acquisition unit 202, an approach warning determination unit 203, and an output control unit 204.

[0049] The vehicle detection unit 201 is a functional unit that detects the position of another vehicle based on a captured image acquired from the imaging unit 6 that captures the surroundings of the vehicle 1, which is the vehicle itself. The vehicle detection unit 201 corresponds to a first detection unit and a second detection unit. For example, the vehicle detection unit 201 detects the position of another vehicle by image processing by template matching using a template image of a vehicle prepared in advance. Here, the other vehicle includes not only four-wheeled vehicles such as passenger cars and trucks, but also two-wheeled vehicles such as scooters and motorcycles. In addition, the vehicle detection unit 201 detects the position of a lane boundary line indicating a boundary in the width direction of the road on which the vehicle 1, which is the vehicle itself, is traveling, based on the captured image acquired from the imaging unit 6. The vehicle detection unit 201 is realized, for example, by the CPU 101 shown in FIG. 5 executing a control program.

[0050] The detected vehicle information acquisition unit 202 is a functional unit that acquires the relative speed information, absolute speed information, distance information from the host vehicle 1 to the detected vehicle, position information of the detected vehicle, and position information of the detected lane boundary line based on the positions of other vehicles and lane boundary lines detected by the vehicle detection unit 201, and the speed information of the vehicle 1 acquired from the vehicle speed sensor 17. Hereinafter, the other vehicles detected by the vehicle detection unit 201 will be referred to as the detected vehicles. Hereinafter, the position information of the lane boundary line will be referred to as the lane position information. The detected vehicle information acquisition unit 202 corresponds to the first acquisition unit and the second acquisition unit. Among them, the relative speed information, absolute speed information, distance information, and position information, which are information about the detected vehicle, will be referred to as the detected vehicle information.

[0051] The relative speed of the detected vehicle with respect to vehicle 1, which is the subject vehicle, is obtained from the change in the position of the detected vehicle in the captured image. For example, if the imaging unit 6 is a stereo camera, the relative speed of the detected vehicle is obtained from the time change in distance indicated by the parallax using parallax information obtained from the stereo camera. Also, the speed information obtained from the vehicle speed sensor 17 becomes the absolute speed information of vehicle 1 as it is. Also, for example, if the imaging unit 6 is a stereo camera, the distance indicated by the parallax corresponding to the detected vehicle becomes the distance to the detected vehicle using the parallax information obtained from the stereo camera.

[0052] The detected vehicle information acquisition unit 202 is realized, for example, by the CPU 101 shown in FIG. 5 executing a control program.

[0053] The approach warning determination unit 203 is a functional unit that determines whether or not to issue a warning to the driver of the vehicle 1 about an approaching vehicle, using the detected vehicle information and lane position information acquired by the detected vehicle information acquisition unit 202. As shown in Fig. 6, the approach warning determination unit 203 includes an approach determination unit 203a, a running state determination unit 203b, and a distance determination unit 203c. The approach warning determination unit 203 is realized, for example, by the CPU 101 shown in Fig. 5 executing a control program.

[0054] The approach determination unit 203a is a functional unit that determines whether or not the detected vehicle is approaching the vehicle 1, which is the vehicle itself. The approach determination unit 203a corresponds to a second determination unit. Specifically, the approach determination unit 203a can determine whether or not the detected vehicle is approaching the vehicle 1, based on the relative speed information of the detected vehicle acquired by the detected vehicle information acquisition unit 202. For example, as shown in FIG. 9(a), even if another vehicle 30 traveling in the same lane LN1 as the vehicle 1 is within the vehicle detection range of the vehicle 1, when the relative speed of the other vehicle 30 is negative, that is, when the other vehicle 30 is moving away from the vehicle 1 as shown in FIG. 9(b), the possibility that the other vehicle 30 will collide with or come into contact with the vehicle 1 is small, so there is no need to issue a warning to the driver.

[0055] The running state determination unit 203b is a functional unit that determines the running state of the vehicle 1 and the detected vehicle using the detected vehicle information and lane position information acquired by the detected vehicle information acquisition unit 202. That is, depending on the running state of the vehicle 1 and the detected vehicle determined by the running state determination unit 203b, it is determined whether or not it is necessary to warn the driver of the approach of the detected vehicle. The running state determination unit 203b corresponds to a first determination unit.

[0056] For example, FIG. 7 shows a pattern of a driving state when a warning of the approach of another vehicle 30 is required. FIG. 7(a) shows a pattern of a driving state in which another vehicle 30 approaching the vehicle 1 is traveling straight on the same lane LN1 as the vehicle 1. FIG. 7(b) shows a pattern of a driving state in which the other vehicle 30 approaching the vehicle 1 moves from the lane LN2, which is another lane, across the lane boundary line L to the lane LN1 in which the vehicle 1 is traveling. In other words, in FIG. 7(b), the other vehicle 30 is changing lanes from the lane LN2 to the lane LN1. FIG. 7(c) shows a pattern of a driving state in which the vehicle 1, which is the host vehicle, moves from the lane LN1 to the lane LN2 in which the other vehicle 30 approaching the vehicle 1 is traveling across the lane boundary line L. In other words, in FIG. 7(c), the vehicle 1 is changing lanes from the lane LN1 to the lane LN2 in which the other vehicle 30 approaching the vehicle 1 is traveling. In other words, in FIG. 7(c), the vehicle 1 is changing lanes from the lane LN1 to the lane LN2. Fig. 7(d) shows a traveling state pattern in which the vehicle 1, which is the host vehicle, and the other vehicle 30 move from a state in which they are traveling on the same lane LN1 to a lane LN2, straddling the lane boundary line L. In other words, in Fig. 7(d), both the vehicle 1 and the other vehicle 30 change lanes from the lane LN1 to the lane LN2. In all of the patterns in Figs. 7(a) to 7(d), the vehicle 1 and the other vehicle 30 are traveling on the same lane, or are traveling on the same lane as a result of moving. Therefore, since there is a risk that the other vehicle 30 will collide with or come into contact with the vehicle 1, it is necessary to issue a warning to the driver.

[0057] On the other hand, FIG. 8 shows a pattern of a driving state when a warning of the approach of another vehicle 30 is not required. FIG. 8(a) shows a pattern of a driving state in which another vehicle 30 approaching the vehicle 1 moves from the same lane LN1 as the vehicle 1 to another lane LN2 across the lane boundary line L. In other words, in FIG. 8(a), the other vehicle 30 changes lanes from the lane LN1 to the lane LN2. FIG. 8(b) shows a pattern of a driving state in which the other vehicle 30 approaching the vehicle 1 travels straight on the lane LN2 different from the lane LN1 on which the vehicle 1 travels. FIG. 8(c) shows a pattern of a driving state in which the vehicle 1 moves to the lane LN2 and the other vehicle 30 moves to the lane LN3 from a state in which the vehicle 1 and the other vehicle 30 approaching the vehicle 1 are both traveling on the lane LN1. In other words, in FIG. 8(c), the vehicle 1 changes lanes from the lane LN1 to the lane LN2, and the other vehicle 40 changes lanes from the lane LN1 to the lane LN3. FIG. 8(d) shows a traveling state pattern in which the vehicle 1 travels on the lane LN1 and the other vehicle 30 approaching the vehicle 1 travels on a lane LN3 different from the lane LN1, and then the vehicle 1 moves to the lane LN2. In other words, in FIG. 8(d), the vehicle 1 changes lanes from the lane LN1 to the lane LN2. In any of the patterns in FIG. 8(a) to FIG. 8(d), the vehicle 1 and the other vehicle 30 travel on different lanes, or travel on different lanes as a result of the movement. Therefore, since there is a small risk that the other vehicle 30 will collide with or come into contact with the vehicle 1, there is no need to issue a warning to the driver.

[0058] The distance determination unit 203c is a functional unit that, when the traveling state determination unit 203b determines that a warning of the approach of the detected vehicle is necessary, determines whether or not the distance between the detected vehicle and the vehicle 1 is within a predetermined distance range based on the distance information of the detected vehicle acquired by the detected vehicle information acquisition unit 202. That is, when the distance between the detected vehicle and the vehicle 1 is not within the predetermined distance range, the distance determination unit 203c determines that the risk of collision or contact is low and that it is not necessary to issue a warning to the driver. The distance determination unit 203c corresponds to a third determination unit. Hereinafter, the predetermined distance range between the detected vehicle and the vehicle 1, in which the distance determination unit 203c determines that it is necessary to issue a warning to the driver, may be referred to as a warning range.

[0059] The distance determination unit 203c may change the warning range according to the absolute speed of the detected vehicle acquired by the detected vehicle information acquisition unit 202. For example, as shown in FIG. 10(a), when the absolute speed of the detected vehicle is high, the distance determination unit 203c increases the warning range and performs the above-mentioned determination. On the other hand, as shown in FIG. 10(b), when the absolute speed of the detected vehicle is low, the distance determination unit 203c decreases the warning range and performs the above-mentioned determination. As a result, when the absolute speed of the detected vehicle is high, the vehicle control device 20 can issue an early warning to the driver. Therefore, the driver can take appropriate measures with plenty of time. The distance determination unit 203c may change the warning range according to the relative speed of the detected vehicle acquired by the detected vehicle information acquisition unit 202. For example, when the relative speed of the detected vehicle is high, the distance determination unit 203 may increase the warning range because an early warning is necessary, and when the relative speed of the detected vehicle is low, the distance determination unit 203 may decrease the warning range because an early warning is not necessary.

[0060] Furthermore, the distance determination unit 203c may determine the weather conditions from the captured image obtained by the imaging unit 6, or may change the warning range using weather information obtained by the communication device 18. In this case, for example, the distance determination unit 203c may increase the warning range when it is determined that it is raining. This is because the braking distance of an approaching vehicle increases when it is raining. This allows the vehicle control device 20 to issue an early warning to the driver. This allows the driver to take appropriate measures with plenty of time to spare.

[0061] The distance determination unit 203c may change the warning range according to the type of the other vehicle detected by the vehicle detection unit 201. Examples of the types of the other vehicle include large vehicles, small vehicles, motorcycles, and bicycles. In this case, for example, the distance determination unit 203c may increase the warning range when a large vehicle approaches as the other vehicle. This is because the braking distance of a large vehicle is large. This allows the vehicle control device 20 to issue an early warning to the driver. Therefore, the driver can take appropriate measures with plenty of time to spare. The determination of the type of the other vehicle by the distance determination unit 203c may be based on vehicle type information received by vehicle-to-vehicle communication in addition to image recognition of the captured image.

[0062] In addition, the distance determination unit 203c may change the warning range according to the type of the vehicle 1, which is the vehicle itself. Examples of the type of the vehicle 1 include large vehicles and small vehicles. In this case, for example, the distance determination unit 203c may increase the warning range when the vehicle width or length of the vehicle 1 is large. This is because when the vehicle width or length of the vehicle 1 is large, the weight of the vehicle 1 increases and the braking distance increases. In addition, when the vehicle width or length is large, the distance between the camera mounting position and the end of the vehicle itself increases, so there is a concern that the approaching vehicle will get too close to the vehicle itself if the warning range is not increased. This allows the vehicle control device 20 to issue an early warning to the driver. Therefore, the driver can take appropriate measures with plenty of time to spare.

[0063] The approach warning determination unit 203 may change the warning range according to the driver's driving history or driving skill. In this case, for example, the distance determination unit 203c may reduce the warning range when the driver has a long driving history or high driving skill. This is because it is considered that there is little danger even if the warning frequency is reduced when the driver has a long driving history or high driving skill. This allows the vehicle control device 20 to set the warning frequency according to the driver's driving history or driving skill. In this case, for example, the driving history, driving skill, or warning range can be selected and set via the display device 15, which is a touch panel.

[0064] The output control unit 204 is a functional unit that performs control to output a warning to the driver of the vehicle 1, which is the vehicle itself, based on the relationship between the position of the lane boundary line detected by the vehicle detection unit 201 and the position of the other vehicle. Specifically, the output control unit 204 outputs a warning when the approach warning determination unit 203 determines that it is necessary to issue a warning to the driver of the vehicle 1 about the approaching other vehicle. In addition, the output control unit 204 causes, for example, the door mirror 7, the rearview mirror 9, and the display device 15, which are examples of display devices, to display a warning, and causes the speaker 19, which is an audio output device, to output a sound indicating the warning. Note that the output control unit 204 does not need to output a warning from all of the door mirror 7, the rearview mirror 9, the display device 15, and the speaker 19, and may output a warning from at least one of them. The output control unit 204 is realized, for example, by the CPU 101 shown in FIG. 5 executing a control program.

[0065] In addition, some or all of the above-mentioned vehicle detection unit 201, detected vehicle information acquisition unit 202, approach warning determination unit 203 and output control unit 204 may be realized by hardware circuits such as an FPGA (Field-Programmable Gate Array) or an ASIC (Application Specific Integrated Circuit) rather than by software programs.

[0066] Further, each of the functional units of the vehicle control device 20 shown in Fig. 6 is shown conceptually, and is not limited to such a configuration. For example, the multiple functional units illustrated as independent functional units in the vehicle control device 20 shown in Fig. 6 may be configured as one functional unit. On the other hand, the function of one functional unit in the vehicle control device 20 shown in Fig. 6 may be divided into multiple functions and configured as multiple functional units.

[0067] (Vehicle approach warning processing of vehicle control device) Fig. 11 is a diagram showing an example of a flow of a vehicle approach warning process of the vehicle control device according to the embodiment. Fig. 12 is a diagram showing an example of a flow of a vehicle approach detection process of the vehicle control device according to the embodiment. The flow of the vehicle approach warning process of the vehicle control device 20 according to the present embodiment will be described with reference to Figs. 11 and 12.

[0068] <Step S1> The vehicle control device 20 executes the vehicle approach detection process to determine whether or not there is another vehicle approaching the vehicle 1 and whether or not it is necessary to issue a warning about the approaching other vehicle to the driver of the vehicle 1. The vehicle approach detection process will be described later with reference to Fig. 12. Then, the process proceeds to step S2.

[0069] <Step S2> If it is necessary to issue a warning as a result of the vehicle approach detection process (step S2: Yes), the process proceeds to step S3, and if it is not necessary (step S2: No), the process returns to step S1. Note that if the output control unit 204 is outputting a warning when returning to step S1, the output of the warning is stopped, and the process returns to step S1.

[0070] <Step S3> The output control unit 204 of the vehicle control device 20 outputs a warning about the approaching vehicle to the driver of the vehicle 1. Specifically, the output control unit 204, for example, causes the door mirror 7, the rearview mirror 9, and the display device 15 to display a warning, and causes the speaker 19 to output a sound indicating the warning. Then, the process returns to step S1 and repeats the process.

[0071] Hereinafter, a flow of the vehicle approach detection process by the vehicle control device 20 according to this embodiment will be described with reference to Fig. 12. Note that the vehicle approach detection process shown in Fig. 12 is a process corresponding to step S1 shown in Fig. 11.

[0072] <Step S11> First, the vehicle detection unit 201 of the vehicle control device 20 detects the presence or absence of another vehicle in the imaging range based on the captured image acquired from the imaging unit 6 that captures the surroundings of the host vehicle, the vehicle 1. The vehicle detection unit 201 also detects the position of a lane boundary line indicating the boundary in the width direction of the road on which the host vehicle, the vehicle 1, is traveling, based on the captured image acquired from the imaging unit 6. As a result, if another vehicle is detected (step S11: Yes), the process proceeds to step S12, and if not detected (step S11: No), the process proceeds to step S19. Hereinafter, the other vehicle detected by the vehicle detection unit 201 will be referred to as a detected vehicle.

[0073] <Step S12> The detected vehicle information acquisition unit 202 of the vehicle control device 20 acquires detected vehicle information and lane position information about the detected vehicle based on the positions of the detected vehicle and lane boundary lines, and the speed information of the vehicle 1 acquired from the vehicle speed sensor 17. Then, the process proceeds to step S13.

[0074] <Step S13> The approach determination unit 203a of the vehicle control device 20 determines whether or not the detected vehicle is approaching the host vehicle, that is, the vehicle 1, based on the relative speed information of the detected vehicle acquired by the detected vehicle information acquisition unit 202. If the detected vehicle is approaching the vehicle 1 (step S13: Yes), the process proceeds to step S14. On the other hand, if the detected vehicle is not approaching the vehicle 1 (step S13: Yes), it is determined that there is no need to issue a warning to the driver, and the process proceeds to step S19.

[0075] <Step S14> The running state determination unit 203b of the vehicle control device 20 determines whether the vehicle 1, which is the vehicle itself, is running straight in the own lane or is moving across a lane boundary line, based on the detected vehicle position information and lane position information acquired by the detected vehicle information acquisition unit 202. In other words, the running state determination unit 203b determines whether the vehicle 1 is running straight or is changing lanes. If the vehicle 1 is running straight (step S14: running straight), the process proceeds to step S15, and if the vehicle 1 is changing lanes (step S14: changing lanes), the process proceeds to step S16.

[0076] <Step S15> The traveling state determination unit 203b further determines whether the detected vehicle is traveling in the lane in which the vehicle 1 is traveling or is moving into the lane. If the detected vehicle is traveling in the lane in which the vehicle 1 is traveling or is moving into the lane (step S15: Yes), the process proceeds to step S17. On the other hand, if the detected vehicle is neither traveling in the lane in which the vehicle 1 is traveling nor moving into the lane (step S15: No), it is determined that there is no need to issue a warning to the driver, and the process proceeds to step S19.

[0077] <Step S16> When the vehicle 1 is changing lanes, the traveling state determination unit 203b further determines whether the detected vehicle is traveling in the lane into which the vehicle 1 will change lanes, or whether the detected vehicle is moving to the lane into which the vehicle 1 will change lanes. When the detected vehicle is a vehicle traveling in the lane into which the vehicle 1 will change lanes, or a vehicle moving into the lane into which the vehicle 1 will change lanes (step S16: Yes), the process proceeds to step S17. On the other hand, when the detected vehicle is not a vehicle traveling in the lane into which the vehicle 1 will change lanes, and is not a vehicle moving into the lane into which the vehicle 1 will change lanes (step S16: No), it is determined that there is no need to issue a warning to the driver, and the process proceeds to step S19.

[0078] That is, the running state determination by the processing of steps S14 to S16 is a determination by the running state determination unit 203b of whether another vehicle is running in the lane in which the host vehicle 1 is running, or whether the other vehicle and the host vehicle are about to run in the same lane, based on the position information and lane position information acquired by the detected vehicle information acquisition unit 202. It can also be said that the running state determination unit 203b determines whether there is another vehicle in the lane in which the host vehicle 1 is running, or in the lane to which the host vehicle is changing lanes, or whether the other vehicle is about to change lanes, based on the position information and lane position information acquired by the detected vehicle information acquisition unit 202.

[0079] <Step S17> The distance determination unit 203c of the vehicle control device 20 determines whether or not the distance between the detected vehicle and vehicle 1 is within a predetermined warning range, based on the distance information of the detected vehicle acquired by the detected vehicle information acquisition unit 202. Hereinafter, the predetermined distance range between the detected vehicle and vehicle 1, for which the distance determination unit 203c determines that it is necessary to issue a warning to the driver, may be referred to as the warning range. If the distance between the detected vehicle and vehicle 1 is within the warning range (step S17: Yes), the process proceeds to step S18. On the other hand, if the distance between the detected vehicle and vehicle 1 is outside the warning range (step S17: No), it is determined that it is not necessary to issue a warning to the driver, and the process proceeds to step S19.

[0080] <Step S18> The approach warning determination unit 203 determines that it is necessary to issue a warning to the driver based on the results of the determinations made by the approach determination unit 203a, the running state determination unit 203b, and the distance determination unit 203c. This ends the vehicle approach detection process, and the process proceeds to step S2 in FIG.

[0081] <Step S19> The approach warning determination unit 203 determines that it is not necessary to issue a warning to the driver, and ends the vehicle approach detection process, and proceeds to step S2 in FIG.

[0082] As described above, in the vehicle control device 20 according to this embodiment, the vehicle detection unit 201 detects the position of the lane boundary line indicating the boundary line in the width direction of the road on which the vehicle 1 is traveling based on the captured image captured by the imaging unit 6 that captures the surroundings of the vehicle 1, which is the vehicle itself, and detects the position of another vehicle based on the captured image, and the output control unit 204 performs control to output a warning to the driver of the vehicle itself based on the relationship between the position of the lane boundary line detected by the vehicle detection unit 201 and the position of the other vehicle. This makes it possible to suppress a situation in which a warning is always issued when an approaching vehicle is detected even when no particular danger is predicted, and to issue a warning when danger is predicted.

[0083] The program executed by the vehicle control device 20 according to the embodiment described above is provided in a state where it is pre-installed in a ROM or the like. The program executed by the vehicle control device 20 may be provided by recording it in a computer-readable storage medium such as a CD-ROM, a flexible disk (FD), a CD-R, or a DVD (Digital Versatile Disk) in an installable or executable format. The above-mentioned program may be provided to the vehicle control device 20 via a network such as the Internet. The program to be executed by the vehicle control device 20 according to the embodiment described above has a modular configuration including each of the above-mentioned functional units. As for the actual hardware of the vehicle control device 20, for example, the CPU 101 reads out and executes the program from the ROM 103, so that each of the above-mentioned multiple functional units is loaded onto the RAM 102, which is a main storage device, and each of the above-mentioned multiple functional units is generated on the RAM 102.

[0084] Although the embodiments and modifications of the present disclosure have been described, they are presented as examples and are not intended to limit the technical scope of the invention. These embodiments and modifications can be implemented in various other forms, and various omissions, substitutions, modifications, and combinations can be made without departing from the spirit of the invention. These embodiments and modifications are included within the scope and spirit of the invention, as well as within the scope of equivalents of the invention described in the claims. [Explanation of symbols]

[0085] 1 vehicle 2. Body 3, 3F, 3R wheels 4 seats 5 Vehicle drive unit 6, 6a, 6b Imaging section 7, 7L, 7R door mirrors 8. Back Seat 9. Rearview mirror 10 Engine switch 11 Handle 12 Shift lever 13 Parking brake 14 Door lock device 15 Display device 16 GPS Sensor 17 Vehicle speed sensor 18 Communication Equipment 19 Speaker 20 Vehicle control device 30 Other vehicles 101 CPU 102 RAM 103 ROM 104 Imaging I / F 105 Display I / F 106 GPS I / F 107 Vehicle speed I / F 108 Communication I / F 109 Audio I / F 110 Bus 201 Vehicle detection unit 202 Detected vehicle information acquisition unit 203 Approach warning determination section 203a Approach judgment part 203b Driving state determination unit 203c Distance judgment section 204 Output control section CAR area L lane markings LAR area LN1~LN3 lanes RAR area

Claims

1. a first detection unit that detects the position of a lane boundary line that indicates a boundary in a width direction of a road on which the host vehicle is traveling, based on an image captured by an imaging unit that captures an image of the surroundings of the host vehicle; A second detection unit that detects a position of another vehicle based on the captured image; a first acquisition unit that acquires lane position information indicating a position of the lane boundary line detected by the first detection unit; a second acquisition unit that acquires position information indicating a position of the other vehicle detected by the second detection unit, distance information of the other vehicle based on the position of the other vehicle, and absolute speed information of the host vehicle from a vehicle speed detection unit; a first determination unit that performs a driving state determination as to whether the other vehicle and the host vehicle are traveling in the same lane, or whether the other vehicle and the host vehicle are about to enter a state in which they will travel in the same lane, based on the lane position information acquired by the first acquisition unit and the position information acquired by the second acquisition unit; a third determination unit that, when it is determined by the first determination unit that the other vehicle and the host vehicle are traveling on the same lane, or when it is determined that the other vehicle and the host vehicle are about to enter a state of traveling on the same lane, changes a predetermined distance range in accordance with the absolute speed information, and determines whether or not the distance between the other vehicle and the host vehicle is within the changed distance range based on the distance information; an output control unit that performs control to output a warning to a driver of the host vehicle when the third determination unit determines that the distance between the other vehicle and the host vehicle is within the distance range; A control device comprising:

2. The second acquisition unit acquires relative speed information of the other vehicle based on the position of the other vehicle detected by the second detection unit, a second determination unit that determines whether the other vehicle is approaching the host vehicle based on the relative speed information, The control device according to claim 1 , wherein the first determination unit performs the traveling state determination when the second determination unit determines that the other vehicle is approaching the host vehicle.

3. 3. The control device according to claim 1 or 2, wherein the first determination unit determines, as the driving state determination, whether the other vehicle is in the lane in which the host vehicle is traveling or in the lane to which the host vehicle is changing lanes, or whether the other vehicle is about to change lanes, based on the lane position information acquired by the first acquisition unit and the position information acquired by the second acquisition unit.

4. 4. The control device according to claim 1, wherein the output control unit causes a display device to display an indication of the warning as an output of a warning to a driver of the host vehicle.

5. 4. The control device according to claim 1, wherein the output control unit causes a sound output device to output a sound indicating the warning as a warning output to a driver of the host vehicle.

6. a first detection step of detecting a position of a lane boundary line indicating a boundary in a width direction of a road on which the host vehicle is traveling, based on an image captured by an imaging unit that captures an image of the surroundings of the host vehicle; a second detection step of detecting a position of another vehicle based on the captured image; a first acquisition step of acquiring lane position information indicating the positions of the lane boundary lines detected in the first detection step; a second acquisition step of acquiring position information indicating a position of the other vehicle detected in the second detection step, distance information of the other vehicle based on the position of the other vehicle, and absolute speed information of the host vehicle from a vehicle speed detection unit; a first determination step of determining a traveling state of whether the other vehicle and the host vehicle are traveling in the same lane or whether the other vehicle and the host vehicle are about to travel in the same lane, based on the lane position information acquired in the first acquisition step and the position information acquired in the second acquisition step; a third determination step of changing a predetermined distance range in accordance with the absolute speed information when it is determined in the first determination step that the other vehicle and the host vehicle are traveling in the same lane, or when it is determined that the other vehicle and the host vehicle are about to enter a state of traveling in the same lane, and determining whether or not the distance between the other vehicle and the host vehicle is within the changed distance range based on the distance information; an output control step of performing control to output a warning to a driver of the host vehicle when it is determined in the third determination step that the distance between the other vehicle and the host vehicle is within the distance range; A warning control method comprising:

7. On the computer, a first detection step of detecting a position of a lane boundary line indicating a boundary in a width direction of a road on which the host vehicle is traveling, based on an image captured by an imaging unit that captures an image of the surroundings of the host vehicle; a second detection step of detecting a position of another vehicle based on the captured image; a first acquisition step of acquiring lane position information indicating the positions of the lane boundary lines detected in the first detection step; a second acquisition step of acquiring position information indicating a position of the other vehicle detected in the second detection step, distance information of the other vehicle based on the position of the other vehicle, and absolute speed information of the host vehicle from a vehicle speed detection unit; a first determination step of determining a traveling state of whether the other vehicle and the host vehicle are traveling in the same lane or whether the other vehicle and the host vehicle are about to travel in the same lane, based on the lane position information acquired in the first acquisition step and the position information acquired in the second acquisition step; a third determination step of changing a predetermined distance range in accordance with the absolute speed information when it is determined in the first determination step that the other vehicle and the host vehicle are traveling in the same lane, or when it is determined that the other vehicle and the host vehicle are about to enter a state of traveling in the same lane, and determining whether or not the distance between the other vehicle and the host vehicle is within the changed distance range based on the distance information; an output control step of performing control to output a warning to a driver of the host vehicle when it is determined in the third determination step that the distance between the other vehicle and the host vehicle is within the distance range; A program for executing the above.

Images