Driving Support Devices

Abstract

To provide a driving support device for improving ghost determination accuracy by enhancing accuracy in recognizing a boundary structure (i.e. guardrail, tunnel wall, and sound-proof wall), thereby to reduce a possibility to perform unnecessary pre-collision control with respect to a ghost.SOLUTION: A driving support device includes: a first sensor for detecting an object in an environment of a vehicle based on reflection of a transmitted wireless medium; a second sensor for detecting a boundary structure positioned at a boundary between a road area on which the vehicle travels and an area other than the road area; and a control unit for performing pre-collision control to avoid a collision with a recognized object being the object detected by the first sensor. When a back position condition indicating that the recognized object is positioned at the back of the boundary structure with respect to the vehicle is established, the control unit reduces a possibility to perform the pre-collision control compared with a case without the establishment of the back position condition.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a driving assistance device that performs pre-collision control to avoid a collision with an object. [Background technology]

[0002] Conventionally, there is known a driving support device that performs pre-collision control for an object detected by a millimeter wave radar mounted on a vehicle. The millimeter wave radar detects an object by transmitting radio waves (millimeter waves) with a wavelength of 1 mm to 10 mm and receiving the millimeter waves reflected by the object.

[0003] A sensor that detects an object by reflection of a wireless medium such as radio waves will erroneously detect the object at a position different from the actual position of the object if the wireless medium is reflected by another object before reaching the sensor. Such an erroneously detected object is called a "ghost." Such further reflections (secondary reflections) by other objects are highly likely to occur from structures (boundary structures) located at the boundary between the road area and the area other than the road area, such as guardrails, tunnel walls, and soundproof walls.

[0004] For example, the driving support device described in Patent Document 1 (hereinafter referred to as the "conventional device") obtains an actual line corresponding to a boundary structure such as a wall based on the detection result of a millimeter wave radar, and obtains a base line based on the actual line. The conventional device then determines that an object located outside (behind) the base line with respect to the vehicle is a ghost. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2001-116839 A Summary of the Invention

[0006] Conventional devices detect both objects and actual lines using a single millimeter wave radar. When the millimeter wave reflected by an object (hereinafter referred to as the "object reflected wave") is further reflected by a boundary structure, the millimeter wave radar recognizes the point (hereinafter referred to as the "secondary reflection point") where the object reflected wave from the boundary structure is further reflected as a ghost.

[0007] Conventional devices obtain "lines of continuously detected stationary objects" as actual lines (see paragraph 0010). When subreflection occurs, conventional devices may not be able to detect the subreflection points of boundary structures as "continuously detected stationary objects." As a result, conventional devices may not be able to determine ghosts because they are unable to obtain actual lines.

[0008] The present invention has been made to address the above-mentioned problems. That is, one of the objects of the present invention is to provide a driving assistance device that improves the accuracy of boundary structure recognition to improve the accuracy of ghost determination and reduce the possibility of unnecessary pre-crash control being performed for a ghost.

[0009] The driving assistance device of the present invention (hereinafter referred to as the "device of the present invention") is a first sensor (22, 24L, 24R) for detecting an object outside the vehicle based on reflection of a transmitted wireless medium; a second sensor (26, 28L, 28R) for detecting a boundary structure located at a boundary between a road area on which the vehicle can travel and an area other than the road area; a control unit (20, 30, 40, 50) that executes pre-collision control to avoid a collision with a recognized object that is an object detected by the first sensor; Equipped with The control unit is configured to make the possibility of executing the pre-collision control lower when a deep position condition is met that the recognized object is located behind the boundary structure relative to the vehicle than when the deep position condition is not met (step 435, step 615 "Yes", step 625).

[0010] According to the device of the present invention, the boundary structure is detected using a second sensor different from the first sensor that detects the recognized object that is the target of the pre-collision control. As a result, even if the first sensor detects a ghost caused by the secondary reflection of the boundary structure, the device of the present invention can detect the boundary structure without being affected by it. Therefore, the recognition accuracy of the boundary structure can be improved, and the establishment of the deep position condition can be reliably determined. As a result, the possibility of performing unnecessary pre-collision control for the ghost can be reduced.

[0011] In one embodiment of the device of the present invention, The control unit Based on the detection result of the first sensor, a reliability (RD) representing the possibility that the recognized object actually exists is obtained (step 415, step 625); Execute the pre-collision control for a recognized object whose reliability is equal to or greater than a predetermined threshold (step 435, step 445); The pre-collision control is not executed for a recognized object whose reliability is less than the threshold (step 435). A predetermined subtraction value is subtracted from the reliability of the recognized object for which the deep position condition is satisfied (step 625); It is structured as follows.

[0012] As a result, the reliability of the recognized object for which the deep position condition is satisfied is reduced by the subtraction value, so that when the deep position condition is satisfied, the possibility of executing pre-collision control is lower than when the deep position condition is not satisfied, thereby reducing the possibility of executing unnecessary pre-collision control for the ghost.

[0013] In one embodiment of the device of the present invention, The second sensor (26) is a different type of sensor from the first sensors (22, 24L, 24R).

[0014] As a result, even if the first sensor detects a ghost caused by the secondary reflection of the boundary structure, because the second sensor is of a different type from the first sensor, the second sensor can detect the boundary structure more accurately without being affected by the secondary reflection of the boundary structure.

[0015] In the above aspect, the second sensor is a camera (26) that captures an image of the outside world, The control unit Identifying the boundary by dividing the external environment into the road area and a non-road area based on the currently captured image (step 505, step 510); acquiring a depth and a height of an object appearing in the current captured image based on the plurality of captured images captured before the current time (step 515); Identifying, as the boundary structure, an imaged object that is located within a predetermined range based on the boundary, has the depth equal to or greater than a first threshold value, and has the height equal to or greater than a second threshold value (step 525); It is structured as follows.

[0016] As a result, an imaged object whose depth is equal to or greater than the first threshold and whose height is equal to or greater than the second threshold is identified as a boundary structure, thereby enabling the device of the present invention to more accurately detect boundary structures.

[0017] In one embodiment of the device of the present invention, The control unit Obtaining an approximation line of the boundary structure in a vehicle coordinate system with a predetermined reference point of the vehicle as the origin (step 530); It is determined whether or not the deep position condition is satisfied based on the relationship between the approximate line and the position coordinates of the recognized object in the vehicle coordinate system (step 615); It is structured as follows.

[0018] This makes it possible to more accurately determine whether or not the recognized object is located behind the boundary structure relative to the vehicle.

[0019] In one embodiment of the device of the present invention, The second sensor is disposed at a different position from the first sensor.

[0020] If the second sensor is the same type as the first sensor, and if the second sensor is disposed in the same position as the first sensor, the second sensor may detect a ghost when the first sensor detects the ghost. By disposing the second sensor in a position different from the first sensor, the possibility of this happening can be reduced.

[0021] In the above description, in order to facilitate understanding of the invention, the names and / or symbols used in the embodiments described below are added in parentheses to the configurations of the invention corresponding to those embodiments. However, each component of the invention is not limited to the embodiments defined by the names and / or symbols. Other objects, other features, and associated advantages of the present invention will be easily understood from the following description of the embodiments of the present invention, which will be described with reference to the drawings. [Brief description of the drawings]

[0022] [Figure 1] FIG. 1 is a schematic system configuration diagram of a driving assistance device according to an embodiment of the present invention. [Diagram 2] FIG. 2 is an explanatory diagram of the positions of the millimeter wave radars and the forward camera shown in FIG. [Diagram 3] FIG. 3 is an explanatory diagram of an example of operation of the driving support device according to the embodiment of the present invention. [Figure 4] FIG. 4 is a flowchart showing a pre-collision control routine executed by the CPU of the driving assistance ECU shown in FIG. [Diagram 5] FIG. 5 is a flowchart showing a boundary structure identification subroutine executed by the CPU of the driving assistance ECU shown in FIG. [Figure 6] FIG. 6 is a flowchart showing a deep position condition determination subroutine executed by the CPU of the driving assistance ECU shown in FIG. [Figure 7] FIG. 7 is an explanatory diagram of the positions of a left side millimeter-wave radar and a right side millimeter-wave radar according to a second modified example of the embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0023] A driving assistance device (hereinafter referred to as "this assistance device") 10 according to one embodiment of the present invention is mounted on a vehicle VA. As shown in FIG. 1, this assistance device 10 includes a driving assistance ECU (hereinafter referred to as "DSECU") 20, an engine ECU 30, a brake ECU 40, and a meter ECU 50.

[0024] ECU is an abbreviation of Electronic Control Unit, and is an electronic control circuit having a microcomputer including a CPU, ROM, RAM, and an interface (I / F) as its main components. The ECU may also be called a "control unit," "controller," or "computer." The CPU realizes various functions by executing instructions (routines) stored in the memory (ROM). All or some of the above ECUs 20, 30, and 40 may be integrated into one ECU.

[0025] The assistance device 10 includes a forward millimeter-wave radar 22, a left front-side millimeter-wave radar 24L, a right front-side millimeter-wave radar 24R, and a forward camera 26. These are connected to the DSECU 20 so as to be able to exchange data with each other. In the following, when there is no need to distinguish between the forward millimeter-wave radar 22, the left front-side millimeter-wave radar 24L, and the right front-side millimeter-wave radar 24R, they will be referred to as "millimeter-wave radars." Furthermore, they may be referred to as "first sensors."

[0026] The millimeter wave radar 24 detects an object by transmitting millimeter waves and receiving the reflected millimeter waves. The millimeter wave radar 24 identifies the distance to the object, the lateral position and the relative speed of the object, and transmits object information including these to the DSECU 20.

[0027] The forward millimeter-wave radar 22 is disposed near the center in the vehicle width direction at the front end of the vehicle VA, as shown in Fig. 2. The forward millimeter-wave radar 22 receives millimeter waves reflected by an object (a three-dimensional object) located within a detection range DR1 in front of the vehicle VA, and detects the object. The detection range DR1 is a sector-shaped range with a central angle θ1 extending forward in the longitudinal direction of the vehicle VA.

[0028] The left front-side millimeter-wave radar 24L is disposed at the left end in the vehicle width direction at the front end of the vehicle VA, as shown in Fig. 2. The left front-side millimeter-wave radar 24L detects objects located within a detection range DR2L. The detection range DR2L is a sector-shaped range with a central angle θ2 extending diagonally forward to the left of the vehicle VA.

[0029] As shown in Fig. 2, the right front-side millimeter-wave radar 24R is disposed at the right end in the vehicle width direction at the front end of the vehicle VA. The right front-side millimeter-wave radar 24R detects objects located within a detection range DR2R. The detection range DR2R is a sector-shaped range with a central angle θ2 extending diagonally forward to the right of the vehicle VA. The central angles of the detection range DR2L and the detection range DR2R may be the same or different.

[0030] As shown in Fig. 2, the front camera 26 is disposed near the center in the vehicle width direction above the front window of the vehicle VA. That is, the front camera 26 is disposed in a position different from that of the millimeter wave radar. The front camera 26 acquires an image by capturing an image capturing range PR in front of the vehicle VA, and transmits the captured image to the DSECU 20. The image capturing range PR is a sector-shaped range with a central angle θ3 extending forward in the longitudinal direction of the vehicle VA. The front camera 26 may be referred to as a "second sensor."

[0031] The engine ECU 30 is connected to an engine actuator 32. The engine actuator 32 includes a throttle valve actuator that changes the opening degree of a throttle valve of the engine 32a. The engine ECU 30 can change the torque generated by the engine 32a by driving the engine actuator 32. The torque generated by the engine 32a is transmitted to driving wheels via a transmission (not shown). The vehicle VA may include an electric motor as a vehicle drive source instead of or in addition to the engine 32a.

[0032] The brake ECU 40 is connected to a brake actuator 42. The brake actuator 42 includes a hydraulic circuit. The hydraulic circuit includes a master cylinder, a flow path through which braking fluid flows, a plurality of valves, a pump, and a motor for driving the pump. The brake actuator 42 adjusts the hydraulic pressure supplied to a wheel cylinder built into a brake mechanism 42a in response to an instruction from the brake ECU 40. The wheel cylinder generates a frictional braking force on the wheel due to the hydraulic pressure.

[0033] The meter ECU 50 is connected to a display 52 and a speaker 54. The display 52 is disposed in a position facing a driver seated in the driver's seat. For example, the display 52 is a multi-information display. The speaker 54 is disposed in the passenger compartment of the vehicle VA and emits a buzzer sound.

[0034] (Overview of operation) The support device 10 acquires the time to collision, which indicates the time required for an object (hereinafter referred to as a "recognized object") identified based on object information from a millimeter wave radar to collide or come closest to the target. Hereinafter, the time to collision is referred to as "TTC (short for Time To Collision)."

[0035] When the TTC is equal to or less than the threshold time Tth, the support device 10 executes pre-collision control to avoid a collision with the object. The pre-collision control includes at least one of "deceleration control for decelerating the vehicle VA" and "warning control for warning the driver of the possibility of a collision."

[0036] As mentioned above, millimeter wave radar may detect ghosts when "millimeter waves (reflected waves) reflected by an object" are further reflected by another object (such reflection is called a "subreflection"). Objects that are particularly prone to subreflection include guardrails, tunnel walls, and soundproof walls. Guardrails and the like are structures located on the boundary between roads and non-road areas, and are referred to below as "boundary structures S."

[0037] The support device 10 judges whether or not a boundary structure S exists based on the captured image acquired by the front camera 26. If the boundary structure S exists, the support device 10 judges whether or not a deep position condition is satisfied that the recognized object is located deep behind the boundary structure S with respect to the vehicle VA.

[0038] Normally, a millimeter wave radar does not detect an object located behind a boundary structure S relative to the vehicle VA. This is because the millimeter waves transmitted by the millimeter wave radar are reflected by the boundary structure S and do not reach the object located behind it. For this reason, an object for which the deep position condition is met is likely to be a ghost erroneously detected by the millimeter wave radar due to secondary reflection from the boundary structure S.

[0039] Therefore, the support device 10 makes the possibility of executing the pre-collision control for an object for which the deep position condition is satisfied lower than the possibility of executing the pre-collision control for an object for which the deep position condition is not satisfied. This allows the support device 10 to reduce the possibility of executing the pre-collision control for a ghost, and reduces the possibility that the driver feels uncomfortable about the pre-collision control.

[0040] Furthermore, the support device 10 determines whether or not a boundary structure S exists using a second sensor (front camera) different from the first sensor (millimeter wave radar) that detects an object for which pre-collision control is to be executed. As a result, even if the first sensor detects a ghost due to secondary reflection from the boundary structure S, the support device 10 determines whether or not the boundary structure S exists based on the detection result of the second sensor, and therefore can accurately detect the boundary structure S without being affected by the detection of the ghost.

[0041] (Example of operation) An example of the operation of the support device 10 will be described with reference to FIG. The assistance device 10 detects a recognized object N at a position (Xn, Yn) in a vehicle coordinate system (X, Y) with a predetermined reference point of the vehicle VA as the origin O. The vehicle coordinate system (X, Y) has an X axis in the width direction of the vehicle VA and a Y axis in the longitudinal direction of the vehicle VA.

[0042] The support device 10 detects a boundary structure S based on a captured image, and obtains an approximation line SL of the boundary structure S using, for example, the least squares method. The support device 10 then determines whether or not a line segment L between the recognized object N and the origin O intersects with the approximation line SL. If the line segment L and the approximation line SL do not intersect, the support device 10 determines that the deep position condition does not hold. If the line segment L and the approximation line SL intersect, the support device 10 determines that the deep position condition holds. In the example shown in FIG. 3, the line segment L and the approximation line SL intersect, so the support device 10 determines that the deep position condition holds for the recognized object N.

[0043] The support device 10 subtracts a predetermined first subtraction value SV1 from the reliability RD of the recognized object N for which the deep position condition is satisfied. The reliability RD represents the possibility that the recognized object N actually exists, and the higher the reliability RD, the higher the possibility that the recognized object N actually exists.

[0044] This support device 10 adds a predetermined additive value AV to the reliability RD of the recognized object N when the following condition A1 is satisfied, and subtracts a predetermined second subtraction value SV2 from the reliability RD of the recognized object N when the following condition A2 is satisfied. Condition A1: The same recognition object N is detected consecutively a certain number of times or more. Condition A2: A condition in which a recognized object N that had not been detected is suddenly detected

[0045] The support device 10 obtains the TTC of the recognized object N whose reliability RD is equal to or greater than a threshold RDth. In detail, the support device 10 obtains the TTC by dividing the distance to the recognized object N by the relative speed of the recognized object N.

[0046] Then, when the minimum TTC is equal to or less than the threshold time Tth, the support device 10 executes the pre-collision control.

[0047] When executing deceleration control as pre-collision control, the support device 10 controls the engine actuator 32 so that the engine 32a does not generate torque, and controls the brake actuator 42 so that a predetermined friction braking force is generated on the wheels. In detail, the DSECU 20 transmits a deceleration command including a predetermined negative target acceleration to the engine ECU 30 and the brake ECU 40. Upon receiving the deceleration command, the engine ECU 30 controls the engine actuator 32 to close the throttle valve so that the engine 32a does not generate torque. Upon receiving the deceleration command, the brake ECU 40 controls the brake actuator 42 so that a frictional braking force is generated on the wheels so that the acceleration of the vehicle VA coincides with the target acceleration.

[0048] When the assistance device 10 executes warning control as pre-collision control, it causes the meter ECU 50 to display a warning screen on the display 52 to notify the driver of the possibility of a collision, and to emit a buzzer sound from the speaker 54. In detail, the DSECU 20 transmits a warning command to the meter ECU 50. Upon receiving the warning command, the meter ECU 50 displays a warning screen on the display 52 and generates a buzzer sound from the speaker 54.

[0049] The present support device 10 lowers the reliability RD of the recognized object N for which the deep position condition is satisfied, thereby lowering the possibility of executing pre-collision control for the recognized object N for which the deep position condition is satisfied, compared to the possibility of executing pre-collision control for the recognized object N for which the deep position condition is not satisfied. This allows the present support device 10 to reduce the possibility of executing pre-collision control for the ghost.

[0050] (Specific operation) <Pre-collision control routine> The CPU of the DSECU 20 (hereinafter, unless otherwise specified, this refers to the CPU of the DSECU 20) executes a pre-collision control routine shown in the flowchart of FIG. 4 every time a predetermined time has elapsed.

[0051] Therefore, at a predetermined timing, the CPU starts the process from step 400 in FIG. Step 405: The CPU acquires object information from the millimeter wave radar. Step 410: The CPU identifies a recognition object N based on the object information. In detail, the CPU specifies the position coordinates (Xn, Yn) representing the position of the recognized object N in the vehicle coordinate system (X, Y) based on the object information. Furthermore, in step 410, the CPU sets the reliability RD of the recognized object N to an initial value IV.

[0052] Step 415: The CPU sets the reliability RD of the recognition object N. Specifically, the CPU judges whether the above condition A1 and the above condition A2 are satisfied. If the above condition A1 is satisfied, the CPU adds the additional value AV to the reliability RD of the recognized object N, and if the above condition A2 is satisfied, the CPU subtracts the second subtraction value SV2 from the reliability RD of the recognized object N.

[0053] Step 420: The CPU acquires a captured image from the front camera 26. Step 425: The CPU executes a boundary structure identification subroutine for identifying the boundary structure S based on the captured image. The boundary structure identification subroutine will be described later with reference to FIG. Step 430: The CPU determines whether a boundary structure S exists.

[0054] If no boundary structure S exists, the CPU determines "No" in step 430 and executes steps 435 to 445 in order. Step 435: The CPU acquires the TTC of a recognized object N that has a reliability RD equal to or greater than a threshold RDth and has a collision possibility.

[0055] For example, the threshold value RDth, the initial value IV, the additional value AV, the first subtraction value SV1, and the second subtraction value SV2 may be set so that the reliability RD is less than the threshold value RDth when the deep position condition is met. As an example, the above values ​​are set as follows: Threshold RDth:35 Initial value IV: 50 Addition value AV: 10 First subtraction value SV1:30 Second subtraction value SV2:10

[0056] Furthermore, the threshold value RDth, the initial value IV, the addition value AV, the first subtraction value SV1 and the second subtraction value SV2 may be set so that the reliability RD does not become less than the threshold value RDth just because the deep position condition is satisfied, but the reliability RD becomes less than the threshold value RDth when both the deep position condition and the second condition are satisfied.

[0057] The CPU determines that there is a possibility of collision with the vehicle VA or a recognized object N approaching within a predetermined distance from the body of the vehicle VA if the vehicle VA and the recognized object N move while maintaining their current speed and current moving direction. The CPU determines the direction of travel of the vehicle VA based on the vehicle speed, which is the speed of the vehicle VA, and the steering angle of the vehicle VA. The vehicle speed is measured by a vehicle speed sensor (not shown), and the steering angle is measured by a steering angle sensor (not shown). The CPU identifies the moving direction of the recognized object N based on the history of the detected position (Xn, Yn) of the recognized object N.

[0058] Step 440: The CPU identifies the recognition object N that has the smallest TTC. Step 445: The CPU determines whether the minimum TTC is less than or equal to the threshold time Tth.

[0059] If the minimum TTC is greater than the threshold time Tth, the CPU determines "No" in step 445, proceeds to step 495, and ends this routine for the time being.

[0060] On the other hand, if the minimum TTC is equal to or less than the threshold time Tth, the CPU determines "Yes" in step 445 and proceeds to step 450. In step 450, the CPU executes pre-collision control, and proceeds to step 495 to temporarily end this routine.

[0061] When the CPU proceeds to step 430, if a boundary structure S exists, the CPU determines "Yes" in step 430 and proceeds to step 455. In step 435, the CPU executes a deep position condition determination subroutine for determining whether or not the deep position condition is satisfied, and then executes the processes from step 435 onward. The deep position condition determination subroutine will be described later with reference to FIG. 6.

[0062] In step 435 of this routine, the CPU does not obtain the TTC of the recognized object N whose reliability RD is less than the threshold RDth. Therefore, the pre-collision control is not executed for the recognized object N whose reliability RD is less than the threshold RDth.

[0063] <Boundary structure identification subroutine> When the CPU proceeds to step 425 in Fig. 4, it executes the boundary structure identification subroutine shown in the flowchart in Fig. 5. That is, when the CPU proceeds to step 425 in Fig. 4, it starts the process from step 500 in Fig. 5, and executes steps 505 to 530 in order.

[0064] Step 505: The CPU acquires a road area, which is an area where the vehicle VA can travel, based on the captured image. For example, the CPU can use SS (Semantic Segmentation) to segment the captured image into a road area and other areas.

[0065] Step 510: The CPU identifies the boundary between the road area and the other area in the captured image. Step 515: The CPU acquires the depth D and height H of the imaged object, which is an object appearing in the current captured image, based on a plurality of captured images acquired prior to the captured image (current captured image) acquired in 420 shown in Fig. 4. In detail, since the plurality of captured images are captured from different viewpoints, it is possible to identify three-dimensional information (depth D, height H, and width) of the imaged object. For example, the CPU can acquire the depth D and height H of the imaged object by using SfM (Structure from Motion). Step 520: The CPU converts the positions of the boundary and the captured object in the captured image into positions in the vehicle coordinate system (X, Y).

[0066] Step 525: The CPU specifies an image-captured object that satisfies all of the following structure conditions B1 to B3 as a boundary structure S. Condition B1: The image capture object is located in a boundary area having a predetermined width based on the boundary. Condition B2: The depth D of the imaged object is equal to or greater than a depth threshold Dth. Condition B3: The height H of the imaged object is equal to or greater than a height threshold Hth.

[0067] Step 530: The CPU obtains an approximation line SL of the boundary structure S. If, in step 525, no boundary structure S is identified because there is no imaging object that satisfies all of the structure conditions B1 to B3, then in step 530 the CPU does not obtain an approximation line SL. Thereafter, the CPU proceeds to step 595 to temporarily end this routine, and then proceeds to step 430 shown in FIG.

[0068] <Subroutine for determining depth position condition> When the CPU proceeds to step 455 in Fig. 4, it executes the deep position condition determination subroutine shown in the flowchart in Fig. 6. That is, when the CPU proceeds to step 425 in Fig. 4, it starts the process from step 600 in Fig. 6 and executes steps 605 to 615 in order.

[0069] Step 605: The CPU selects a recognition object N to be processed. Hereinafter, the recognition object N selected in step 605 is referred to as the "processing object N." Step 610: The CPU obtains a line segment L that connects the processing object N and the origin O of the vehicle coordinate system (X, Y). Step 615: The CPU determines whether the approximation line SL of the boundary structure S and the line segment L intersect.

[0070] If the approximation line SL and the line segment L do not intersect (i.e., the deep position condition is not satisfied), the CPU determines "No" in step 615 and proceeds to step 620. In step 620, the CPU determines whether or not all the recognition objects N have been selected as processing objects N.

[0071] If all of the recognized objects N have not yet been selected as the processing objects N, the CPU judges "No" in step 620 and returns to step 605, and the CPU selects a processing object N from the recognized objects N that have not yet been selected as the processing objects N, and proceeds to step 610.

[0072] If the approximation line SL and the line segment L intersect when the CPU proceeds to step 615 (i.e., if the deep position condition is satisfied), the CPU determines "Yes" in step 615 and proceeds to step 625. In step 625, the CPU subtracts a first subtraction value SV1 from the reliability RD of the processing object N and proceeds to step 620.

[0073] If all of the recognized objects N have been selected as processing objects when the CPU proceeds to step 620, the CPU judges "Yes" in step 620, proceeds to step 695 to temporarily terminate this routine, and proceeds to step 435 shown in Figure 4.

[0074] In this embodiment, the boundary structure S is detected using a second sensor (forward camera 26) different from the first sensor (millimeter wave radar) for detecting the recognition object N. As a result, even if the first sensor detects a ghost caused by the secondary reflection of the boundary structure S, the boundary structure S can be reliably identified without being affected by the ghost. This makes it possible to prevent a situation in which the deep position condition cannot be determined because the boundary structure S cannot be identified, and makes it possible to more accurately identify the ghost, thereby reducing the possibility of executing pre-collision control for the ghost.

[0075] The present invention is not limited to the above-described embodiment, and various modifications of the present invention can be adopted.

[0076] (First Modification) The first sensor is not limited to a millimeter wave radar, and may be any sensor that detects an object by reflecting a transmitted wireless medium.

[0077] (Second Modification) The second sensor is not limited to a camera. For example, the second sensor may be the same type of sensor as the first sensor (i.e., may be a millimeter wave radar). When the second sensor is a millimeter wave radar, the CPU identifies an object having a length equal to or greater than the length threshold Lth as the boundary structure S.

[0078] As shown in FIG. 7, the assistance device 10 includes a left side millimeter wave radar 28L and a right side millimeter wave radar 28R instead of the front camera 26 as second sensors. 7, the left side millimeter-wave radar 28L is disposed on the left side of the vehicle VA and detects objects located within a detection range DR3L. The detection range DR3L is a sector-shaped range extending leftward in the vehicle width direction of the vehicle VA. 7, the right side millimeter-wave radar 28R is disposed on the left side of the vehicle VA and detects objects located within a detection range DR3R. The detection range DR3R is a sector-shaped range extending toward the right in the vehicle width direction of the vehicle VA.

[0079] If the left side millimeter-wave radar 28L and the left front side millimeter-wave radar 24L were disposed in the same position, the left side millimeter-wave radar 28L would possibly detect a ghost if the left front side millimeter-wave radar 24L detected the ghost. Since the left side millimeter-wave radar 28L is disposed in a different position from the left front side millimeter-wave radar 24L, the possibility of this happening can be reduced.

[0080] For the same reason, the right side millimeter-wave radar 28R is disposed at a position different from that of the right front side millimeter-wave radar 24R.

[0081] (Third Modification) The support device 10 can be mounted on vehicles such as an engine automobile, a hybrid electric vehicle (HEV), a plug-in hybrid electric vehicle (PHEV), a fuel cell electric vehicle (FCEV), and an electric vehicle (BEV). [Explanation of symbols]

[0082] 10...driving assistance device, 20...driving assistance ECU, 22...forward millimeter wave radar, 24L...left front side millimeter wave radar, 24R...right front side millimeter wave radar, 26...forward camera.

Claims

1. a first sensor for detecting an object outside the vehicle based on reflection of the transmitted wireless medium; a second sensor that detects a boundary structure located on a boundary between a road area on which the vehicle can travel and an area other than the road area; a control unit that executes pre-collision control to avoid a collision with a recognized object that is an object detected by the first sensor; Equipped with the control unit is configured to, when a deep position condition is satisfied that the recognized object is located deep inside the boundary structure with respect to the vehicle, make the pre-collision control less likely to be executed than when the deep position condition is not satisfied; Furthermore, the control unit acquiring a reliability indicating a possibility that the recognized object actually exists based on a detection result of the first sensor; Executing the pre-collision control for a recognized object whose reliability is equal to or greater than a predetermined threshold value; The pre-collision control is not executed for a recognized object having a reliability lower than the threshold value. subtracting a predetermined subtraction value from the reliability of the recognized object for which the deep position condition is satisfied; It was configured as follows: Driving assistance device.

2. In the driving assistance device according to claim 1, The second sensor is a different type of sensor from the first sensor. Driving assistance device.

3. In the driving assistance device according to claim 2, the second sensor is a camera that captures an image of the outside world, The control unit Identifying the boundary by dividing the outside world into the road area and a non-road area based on a currently captured image; acquiring a depth and a height of an object appearing in the current captured image based on a plurality of captured images captured before the current time; identifying, as the boundary structure, an imaged object that is located within a predetermined range based on the boundary, has the depth equal to or greater than a predetermined first threshold value, and has the height equal to or greater than a predetermined second threshold value; It was configured as follows: Driving assistance device.

4. In the driving assistance device according to claim 1, The control unit obtaining an approximation line of the boundary structure in a vehicle coordinate system having a predetermined reference point of the vehicle as an origin; determining whether or not the deep position condition is satisfied based on a relationship between the approximation line and a position coordinate of the recognized object in the vehicle coordinate system; It was configured as follows: Driving assistance device.

5. In the driving assistance device according to claim 1, The second sensor is disposed at a position different from that of the first sensor. Driving assistance device.

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