Driving support device

Abstract

To provide a drive assistance device capable of accurately performing drive assistance in the case where a vehicle is traveling in a low visibility condition.SOLUTION: In a case where out of an on-vehicle camera 60, a millimeter wave radar 70 and a laser radar 80, at least only one of the millimeter wave radar 70 and the laser radar 80 detects that an object is present in front of the vehicle 10 and is at rest in front of the vehicle 10, when it is detected by a traveling condition detection unit that the vehicle 10 is traveling in a low visibility condition, a drive assistance unit 20 performs alarm processing at an earlier timing than in a case where it is not detected by the traveling condition detection unit that the vehicle 10 is traveling in a low visibility condition.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a driving support device.

Background Art

[0002] Conventionally, devices for assisting driving operations of vehicles have been widely known. For example, in the device described in Patent Document 1, on the condition that the defroster switch is turned on, it indirectly detects that the vehicle window glass is fogged, and performs driving support such as detecting obstacles or displaying an imaging image outside the vehicle on the screen, so as to assist the driver's vision when the driver's field of vision is poor.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in the conventional technology, for example, in situations such as thick fog or whiteout, when the driver does not operate the defroster, there is a problem that driving support cannot be accurately performed even when the vehicle is running in a situation with poor visibility.

[0005] The present invention has been made in view of such circumstances, and an object thereof is to provide a driving support device that can accurately perform driving support when a vehicle is running in a situation with poor visibility.

Means for Solving the Problems

[0006] The driving support device for solving the above problems includes an object detection unit that detects an object in front of the vehicle, a driving situation detection unit that detects the driving situation of the vehicle, and a driving support unit that performs driving support including warning processing regarding the object detected by the object detection unit. The object detection unit includes a first in-vehicle camera, a millimeter-wave radar, and a lidar. The driving situation detection unit includes a second in-vehicle camera having a function of tracking a subject and a communication device having a function of communicating with an external device. When the weather information at the driving position of the vehicle received by the communication device from the external device indicates heavy fog or snowstorm, or when the second in-vehicle camera tracks an optical flow indicating information regarding the movement of a subject based on a plurality of consecutive image frames in time series, if the number of first optical flows indicating information regarding the movement of a first subject is less than the number of second optical flows indicating information regarding the movement of a second subject located closer to the vehicle than the first subject, it is detected that the vehicle is driving in a situation with poor visibility. When the driving support unit detects that at least one of the millimeter-wave radar and the lidar among the first in-vehicle camera, the millimeter-wave radar, and the lidar detects that the object exists in front of the vehicle and the object is stationary in front of the vehicle, and when it is detected by the driving situation detection unit that the vehicle is driving in a situation with poor visibility, the warning processing is performed at a timing earlier than when it is not detected by the driving situation detection unit that the vehicle is driving in a situation with poor visibility.

Effect of the Invention

[0007] According to the present invention, driving support can be accurately performed when the vehicle is driving in a situation with poor visibility.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Embodiments for Carrying Out the Invention

[0009] Hereinafter, an embodiment in which a driving support device is embodied will be described with reference to the drawings.

[0010] As shown in FIG. 1, a vehicle 10 to which a driving support device is applied includes, for example, a driving support unit 20 that provides various driving supports including collision avoidance support for the vehicle 10, an HMI (Human Machine Interface) 30 that notifies the driver of the support, and an intervention control device 40 that assists in vehicle operation.

[0011] Further, the vehicle 10 includes, for example, an in-vehicle camera 60, a millimeter-wave radar 70, a lidar 80, a communication device 90, a map data storage unit 100, and a current position acquisition unit 110.

[0012] The in-vehicle camera 60 images a predetermined range in front of the vehicle 10 by, for example, a CCD camera installed on the back side of the rearview mirror. In this regard, the in-vehicle camera 60 is an example of a first in-vehicle camera and constitutes an object detection unit. The in-vehicle camera 60 outputs an image signal based on the captured image to the driving support unit 20.

[0013] Further, the in-vehicle camera 60 has a function of tracking a subject. The in-vehicle camera 60 tracks an optical flow indicating information on the movement of the subject based on a plurality of image frames that are temporally continuous. When the number of the first optical flows indicating information on the movement of the first subject in the in-vehicle camera 60 is smaller than the number of the second optical flows indicating information on the movement of the second subject located closer to the vehicle 10 than the first subject, the in-vehicle camera 60 detects that the vehicle 10 is running in a situation with poor visibility. In this regard, the in-vehicle camera 60 is an example of a second in-vehicle camera and constitutes a driving situation detection unit.

[0014] The millimeter-wave radar 70 detects the position and distance of an object within a predetermined range in front of the vehicle 10 using radio waves with a wavelength of 1 to 10 nm. In this regard, the millimeter-wave radar 70 constitutes an object detection unit. When the millimeter-wave radar 70 detects an object existing in front of the vehicle 10, it outputs a signal including information on the detected object to the driving support unit 20.

[0015] The lidar 80 detects the position and distance of an object within the detection range using laser light with a wavelength of several hundred nm to one thousand and several hundred nm. In this regard, the lidar 80 constitutes an object detection unit. When the lidar 80 detects an object existing in front of the vehicle 10, it outputs a signal including information on the detected object to the driving support unit 20.

[0016] The communication device 90 is configured to be able to receive information regarding the driving environment of the vehicle 10, such as weather information at the driving position of the vehicle, from an external vehicle device. When the weather information at the driving position of the vehicle 10 received from the external vehicle device indicates that it is thick fog or blizzard, the communication device 90 detects that the vehicle 10 is driving in a situation with poor visibility. In this regard, the in-vehicle camera 60 constitutes a driving situation detection unit. When the communication device 90 acquires information regarding the driving environment of the vehicle 10 from the external vehicle device, it outputs the acquired information regarding the driving environment of the vehicle 10 to the driving support unit 20.

[0017] The map data storage unit 100 stores map data including a road map. The map data includes information indicating the latitude and longitude of curves, intersections, one-way roads, stop positions, level crossings, and traffic lights. The driving support unit 20 reads out the map data corresponding to the position by specifying the position of the object detected by the in-vehicle camera 60, the millimeter-wave radar 70, or the lidar 80 in the map data stored in the map data storage unit 100 from the map data storage unit 100.

[0018] The current position acquisition unit 110 includes a GPS 112 used to detect the current position of the vehicle 10. The GPS 112 receives signals from GPS satellites and detects the current position of the vehicle 10 based on the received signals from the GPS satellites. The GPS 112 outputs information indicating the detected current position of the vehicle 10 to the driving support unit 20.

[0019] The HMI 30 is a device that outputs images and sounds recognizable by the driver, such as a voice device, a head-up display, a monitor of a navigation system, and a meter panel. The HMI 30 receives a warning instruction signal from the driving support unit 20 and performs warning control regarding an object located in front of the vehicle 10 by outputting information recognizable by the driver based on the input warning instruction signal.

[0020] The intervention control device 40 is composed of various control devices such as a brake control device that controls the brake actuator of the vehicle 10, and is a device that executes assistance for braking the vehicle 10. The intervention control device 40 receives an intervention control signal from the driving support unit 20 and performs braking control based on the input intervention control signal.

[0021] The driving support unit 20 has, for example, a TTC calculation unit 22 and a support control unit 24.

[0022] The TTC calculation unit 22 calculates, for example, the TTC (Time to Collision), which is the time required for the vehicle 10 to reach the position of the target. The TTC calculation unit 22 calculates, for example, relative position information indicating the positional relationship between the current position of the vehicle 10 detected by the GPS 112 and the position of the object detected by the in-vehicle camera 60, the millimeter-wave radar 70, or the lidar 80. Then, the TTC calculation unit 22 calculates the distance between the vehicle 10 and the object based on the calculated relative position information, and calculates the TTC based on the calculated distance.

[0023] The support control unit 24 performs driving support based on, for example, the TTC calculated by the TTC calculation unit 22. The support control unit 24 performs warning control regarding an object located in front of the vehicle 10, for example, by outputting a warning instruction signal to the HMI 30. Further, the support control unit 24 performs braking control by outputting an intervention control signal to the intervention control device 40, for example.

[0024] Specifically, as shown in FIG. 2, when only the in-vehicle camera 60 among the in-vehicle camera 60 and the millimeter-wave radar 70 detects that an object exists in front of the vehicle 10, the support control unit 24 does not perform driving support regardless of whether the object is a stationary object marker stationary in front of the vehicle 10 or a preceding object marker moving in front of the vehicle 10.

[0025] When only the millimeter-wave radar 70 among the in-vehicle camera 60 and the millimeter-wave radar 70 detects that an object exists in front of the vehicle 10, if the object is a stationary object marker stationary in front of the vehicle 10, the support control unit 24 performs warning processing regarding the object. In this case, when it is detected by the communication device 90 or the in-vehicle camera 60 that the vehicle 10 is traveling in a situation with good visibility, the support control unit 24 performs warning processing regarding the object on the condition that the TTC calculated by the TTC calculation unit 22 is less than the second threshold value. The second threshold value is a value smaller than the first threshold value. On the other hand, when it is detected by the communication device 90 or the in-vehicle camera 60 that the vehicle 10 is traveling in a situation with poor visibility, the support control unit 24 performs warning processing regarding the object on the condition that the TTC calculated by the TTC calculation unit 22 is less than the third threshold value. The third threshold value is a value equal to the first threshold value and larger than the second threshold value.

[0026] Further, when only the millimeter-wave radar 70 among the in-vehicle camera 60 and the millimeter-wave radar 70 detects that there is an object in front of the vehicle 10, and the object is a preceding object moving in front of the vehicle 10, the support control unit 24 performs both the warning process regarding the object and the braking process of the vehicle 10. In this case, the support control unit 24 performs both the warning process regarding the object and the braking process of the vehicle 10 on the condition that the TTC calculated by the TTC calculation unit 22 is less than the first threshold value.

[0027] When both the in-vehicle camera 60 and the millimeter-wave radar 70 detect that there is an object in front of the vehicle 10, the support control unit 24 performs both the warning process regarding the object and the braking process of the vehicle 10 regardless of whether the object is a stationary object standing still in front of the vehicle 10 or a preceding object moving in front of the vehicle 10. In this case, the support control unit 24 performs both the warning process regarding the object and the braking process of the vehicle 10 on the condition that the TTC calculated by the TTC calculation unit 22 is less than the first threshold value.

[0028] That is, when only the millimeter-wave radar 70 among the in-vehicle camera 60 and the millimeter-wave radar 70 detects that there is an object in front of the vehicle 10 and the object is stationary in front of the vehicle 10, and when it is detected by the communication device 90 or the in-vehicle camera 60 that the vehicle 10 is running in a poor visibility situation, the support control unit 24 performs the warning process at a timing earlier than when it is not detected by the communication device 90 or the in-vehicle camera 60 that the vehicle 10 is running in a poor visibility situation.

[0029] Next, the operation of the driving support unit 20 will be described according to the flowchart shown in FIG. 3. The process shown in FIG. 2 is periodically executed in the driving support unit 20.

[0030] As shown in FIG. 3, the driving support unit 20 first determines whether an object existing in front of the vehicle 10 is a preceding object (S10).

[0031] When the driving support unit 20 determines that the object existing in front of the vehicle 10 is a preceding object (S10 = YES), it determines whether the TTC calculated by the TTC calculation unit 22 is less than the first threshold value (S12).

[0032] On the other hand, when the driving support unit 20 determines that the object existing in front of the vehicle 10 is a stationary object (S10 = NO), it determines whether both the millimeter-wave radar 70 and the in-vehicle camera 60 detect the object (S14). When both the millimeter-wave radar 70 and the in-vehicle camera 60 detect the object (S14 = YES), the driving support unit 20 determines whether the TTC calculated by the TTC calculation unit 22 is less than the first threshold value (S11).

[0033] When the driving support unit 20 determines that the TTC calculated by the TTC calculation unit 22 is greater than or equal to the first threshold value (S11 = NO), it returns the process to S10.

[0034] On the other hand, when the driving support unit 20 determines that the TTC calculated by the TTC calculation unit 22 is less than the first threshold value (S11 = YES), it performs warning processing regarding the object through the HMI 30 (S12), performs braking processing of the vehicle 10 through the intervention control device 40 (S13), and ends the flowchart shown in FIG. 3.

[0035] Also, in the previous S14, when the driving support unit 20 determines that at least one of the millimeter-wave radar 70 and the in-vehicle camera 60 does not detect the object (S14 = NO), it determines whether only the millimeter-wave radar 70 among the millimeter-wave radar 70 and the in-vehicle camera 60 detects the object (S15).

[0036] When the driving support unit 20 determines that the millimeter-wave radar 70 does not detect the object among the millimeter-wave radar 70 and the in-vehicle camera 60 (S15 = NO), it returns the process to S10.

[0037] On the other hand, when the driving support unit 20 determines that only the millimeter-wave radar 70 among the millimeter-wave radar 70 and the in-vehicle camera 60 has detected an object (S15 = YES), it determines whether the driving environment of the vehicle 10 detected by the communication device 90 or the in-vehicle camera 60 is in good visibility (S16).

[0038] When the driving support unit 20 determines that the driving environment of the vehicle 10 detected by the communication device 90 or the in-vehicle camera 60 is in good visibility (S16 = YES), it determines whether the TTC calculated by the TTC calculation unit 22 is less than the second threshold value (S17).

[0039] When the driving support unit 20 determines that the TTC calculated by the TTC calculation unit 22 is greater than or equal to the second threshold value (S17 = NO), it returns the process to S10. On the other hand, when the driving support unit 20 determines that the TTC calculated by the TTC calculation unit 22 is less than the second threshold value (S17 = YES), it performs warning processing regarding the object through the HMI 30 (S18) and ends the flowchart shown in FIG. 3.

[0040] When the driving support unit 20 determines in the previous S16 that the driving environment of the vehicle 10 detected by the communication device 90 or the in-vehicle camera 60 is in poor visibility (S16 = NO), it determines whether the TTC calculated by the TTC calculation unit 22 is less than the third threshold value (S19).

[0041] When the driving support unit 20 determines that the TTC calculated by the TTC calculation unit 22 is greater than or equal to the third threshold value (S19 = NO), it returns the process to S10. On the other hand, when the driving support unit 20 determines that the TTC calculated by the TTC calculation unit 22 is less than the third threshold value (S19 = YES), it performs warning processing regarding the object through the HMI 30 (S18) and ends the flowchart shown in FIG. 3.

[0042] The above embodiment can also be implemented in the following forms.

[0043] · In the above-described embodiment, when the support control unit 24 detects that only the millimeter-wave radar 70 among the in-vehicle camera 60 and the millimeter-wave radar 70 has an object in front of the vehicle 10 and the object is stationary in front of the vehicle 10, and it is detected by the communication device 90 or the in-vehicle camera 60 that the vehicle 10 is running in a situation with poor visibility, the support control unit 24 performs warning processing at a timing earlier than when it is not detected by the communication device 90 or the in-vehicle camera 60 that the vehicle 10 is running in a situation with poor visibility. Instead of this, when the support control unit 24 detects that at least one of the millimeter-wave radar 70 and the lidar 80 among the in-vehicle camera 60, the millimeter-wave radar 70, and the lidar 80 has an object in front of the vehicle 10 and the object is stationary in front of the vehicle 10, the above-described warning processing may be performed.

[0044] Note that the embodiments described above are for facilitating the understanding of the present invention and are not for limiting and interpreting the present invention. The present invention can be changed / improved without departing from its gist, and equivalents thereof are also included in the present invention. That is, what those skilled in the art appropriately modify in each embodiment is also included in the scope of the present invention as long as it has the features of the present invention. For example, each element included in each embodiment and its arrangement, material, conditions, shape, size, etc. are not limited to those illustrated and can be appropriately changed. Also, it goes without saying that each embodiment is an example, and partial substitution or combination of the configurations shown in different embodiments is possible, and these are also included in the scope of the present invention as long as they include the features of the present invention.

Explanation of Reference Numerals

[0045] 10... Vehicle, 20... Driving Support Unit, 22... TTC Calculation Unit, 24... Support Control Unit, 30... HMI, 40... Intervention Control Device, 60... In-vehicle Camera, 70... Millimeter-wave Radar, 80... Lidar, 90... Communication Device, 100... Map Data Storage Unit, 110... Current Position Acquisition Unit, 112... GPS.

Claims

【Claim 1】 An object detection unit that detects an object in front of the vehicle; A driving situation detection unit that detects the driving situation of the vehicle; A driving support unit that performs driving support including warning processing regarding the object detected by the object detection unit; Comprising: The object detection unit includes a first in-vehicle camera, a millimeter-wave radar, and a lidar; The driving situation detection unit includes a second in-vehicle camera having a function of tracking a subject and a communication device having a function of communicating with an external vehicle device. When the weather information at the driving position of the vehicle received by the communication device from the external vehicle device indicates that it is thick fog or snowstorm, or when the second in-vehicle camera tracks an optical flow indicating information regarding the movement of a subject based on a plurality of consecutive image frames in time series, if the number of first optical flows indicating information regarding the movement of a first subject is less than the number of second optical flows indicating information regarding the movement of a second subject located closer to the first subject, it is detected that the vehicle is driving in a situation with poor visibility. When the driving support unit detects that at least one of the millimeter-wave radar and the lidar among the first in-vehicle camera, the millimeter-wave radar, and the lidar is such that the object exists in front of the vehicle and the object is stationary in front of the vehicle, and when it is detected by the driving situation detection unit that the vehicle is driving in a situation with poor visibility, the warning processing is performed at a timing earlier than when it is not detected by the driving situation detection unit that the vehicle is driving in a situation with poor visibility. A driving support device.

Images