Collision avoidance assistance device

Abstract

Collision avoidance assistance device for a vehicle, with: a forward-direction camera sensor configured to capture an image of a forward-direction camera detection area in order to obtain forward-direction camera sensor information, wherein the forward-direction camera detection area is an area between a diagonally oriented front-left direction of the vehicle and a diagonally oriented front-right direction of the vehicle; a forward direction radar sensor configured to obtain forward direction radar sensor information about an object located within a forward direction radar detection area, wherein the forward direction radar detection area is an area between a diagonally oriented front-left direction of the vehicle and a diagonally oriented front-right direction of the vehicle; and a control unit configured to perform collision avoidance steering control based on forward-direction camera sensor information to move the vehicle into a collision avoidance space to prevent a collision between the vehicle and an obstacle when, based on forward-direction radar sensor information, it is determined that an object is present as the obstacle that is highly likely to collide with the vehicle, the control unit is configured to: to determine, on the basis of the forward-direction camera sensor information and the forward-direction radar sensor information, whether a first condition is met or not, wherein the first condition is a condition which is met if it is determined that a specific space exists as a collision avoidance space, wherein the specific space overlaps with an adjacent lane which is adjacent to a lane of the carrier vehicle on which the vehicle is traveling; to determine, based on environmental information about a section in the vicinity of an edge of the adjacent lane on the opposite side of the carrier vehicle's lane, wherein the environmental information is contained in the forward-direction camera sensor information and / or the forward-direction radar sensor information, whether a second condition is met or not, wherein the second condition is a condition that is met if a present situation is a predetermined specific situation in which it is predicted that there is no object about to enter the adjacent lane from an area outside a road of the carrier vehicle, which is a road on which the carrier vehicle is traveling; and to perform the collision avoidance steering control to allow the vehicle to move into the specific space when it is determined that an operating permit condition is met, wherein the operating permit condition is a condition which is met when at least both the first condition and the second condition are determined to be met.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to a collision avoidance assist device configured to avoid a collision between a host vehicle and an obstacle by autonomous steering. BACKGROUND

[0002] A collision avoidance assistance device is known which is configured to: To detect an obstacle with a high probability (collision probability) of colliding with a host vehicle, using a forward obstacle detection sensor such as a camera sensor and a radar sensor; to issue a warning to the driver when the obstacle with the high probability of collision is detected; and to brake the host vehicle autonomously when the probability of a collision increases in order to assist the driver in avoiding the collision.

[0003] The collision avoidance assistance device proposed in Japanese patent application JP 2017-43262 A is configured to perform autonomous steering to change a direction of movement of the host vehicle to a direction that enables the host vehicle to avoid collision with the obstacle when the collision probability remains high even after the host vehicle has begun braking. DE 10 2012 218 361 A1 describes a method for safely operating a motor vehicle, in which evasive steering assistance is provided and, if it is necessary to evade to an adjacent lane, the traffic in that lane is also taken into account. Furthermore, DE 10 2014 114 827 A1 discloses a system and method for calculating an evasive steering path around a target object, e.g., a target vehicle that has stopped or is traveling slowly in front of the subject vehicle.In addition, US 2018 / 0 326 981 A1 describes a control device for a vehicle with an adaptation of detection areas, whereby an object in the adjacent lane is also taken into account during an evasive maneuver around an object. SUMMARY

[0004] In order to perform autonomous steering to avoid an obstacle, a space (referred to as the “collision avoidance space”) must be available into which the host vehicle moves.

[0005] For example, the proposed collision avoidance assistance device is configured to: to determine whether a collision avoidance route / path is present (or exists) in a lane of the host vehicle, which is a lane in which the host vehicle is traveling, wherein the collision avoidance route is a route along which the host vehicle can move to avoid the collision; and to perform the steering control such that the host vehicle only moves on the collision avoidance route when it is determined that the collision avoidance route is in the host vehicle's lane.

[0006] However, there may be a case where a collision avoidance space exists in a lane (hereinafter referred to as the "adjacent lane") adjacent to the host vehicle's lane, even if the collision avoidance space cannot be found within the host vehicle's lane. In such a case, by having the host vehicle travel along a collision avoidance route leading to the collision avoidance space in the adjacent lane, the collision can be avoided even if the host vehicle deviates from the host vehicle's lane. This can increase the number of operation scenarios in which autonomous steering can be performed to avoid the collision.

[0007] To perform the autonomous steering described above in multiple scenarios, it is preferable to employ additional sensors to detect objects located at a larger area in front of the host vehicle. Meanwhile, a vehicle employing systems for implementing driver assistance systems typically includes a forward (front) camera sensor and a forward (front) radar sensor. However, these sensors are not sufficient to detect objects located at a larger area in front of the host vehicle. Therefore, additional sensors (e.g., radar sensors for the forward-side direction) may be required. The radar sensors for the forward-side direction are arranged, for example, at a right front corner of a vehicle body and at a left front corner of the vehicle body, respectively.A central axis of the radar wave emitted by each of the radar sensors for the forward-side direction runs diagonally forward and outward. This configuration can extend the detection range to the lateral direction of the host vehicle and detect the movement of an object within the wider detection range.

[0008] However, the above configuration with the additional sensors requires high costs and a significant amount of time to develop a system that can accurately detect / recognize the object. Furthermore, the above configuration can require significant memory capacity and increase the computational load.

[0009] The present disclosure was made to solve the problems described above. One of the objectives of this disclosure is to provide a collision avoidance device with a simple configuration, according to which the vehicle can deviate from the traveling lane of the host vehicle when necessary to avoid the collision while ensuring safety.

[0010] In some embodiments of the present disclosure, a collision avoidance assist device for a vehicle (ie, a host vehicle) comprises: a forward camera sensor (11) configured to capture an image of a forward camera detection area to obtain forward camera sensor information, the forward camera detection area being an area between a diagonal front-left direction of the vehicle and a diagonal front-right direction of the vehicle; a forward radar sensor (12) configured to obtain forward radar sensor information about an object located in a forward radar detection range, the forward radar detection range being a range between a diagonal front-left direction of the vehicle and a diagonal front-right direction of the vehicle; and a control unit (10) configured to perform collision avoidance steering control based on the forward camera sensor information to make the vehicle move into a collision avoidance space to avoid a collision between the vehicle and an obstacle when it is determined based on forward radar sensor information that an object is present as the obstacle that is highly likely to collide with the vehicle, wherein the control unit is configured to: determining, based on the forward camera sensor information and the forward radar sensor information, whether or not a first condition is satisfied, the first condition being a condition that is satisfied when it is determined that a specific space exists as a collision avoidance space, the specific space overlapping with a neighboring lane adjacent to a lane of the host vehicle on which the vehicle is traveling (S13); based on environmental information about a portion in the vicinity of an edge of the adjacent lane on the opposite side of the host vehicle's lane, the environmental information being included in the forward camera sensor information and / or the forward radar sensor information, to determine whether or not a second condition is satisfied, the second condition being a condition that is satisfied when a current situation is a predetermined specific situation in which it is predicted that there is no object about to enter the adjacent lane from an area outside a road of the host vehicle, which is a road on which the host vehicle is traveling (S14-S16); and perform the collision avoidance steering control to make the vehicle move into the specific space when it is determined that an execution permission condition is satisfied, wherein the execution permission condition is a condition that is satisfied when at least both the first condition and the second condition are determined to be satisfied (S19).

[0011] In some embodiments of the present disclosure, a collision avoidance assist device for a host vehicle comprises: a forward direction detecting means (11, 12) configured to detect a three-dimensional object and a white line (road marking line applied to a road) in an area in front of the host vehicle and between a diagonal front-left direction of the host vehicle and a diagonal front-right direction of the host vehicle; and collision avoidance steering control means (10, S19) for performing collision avoidance steering control, which is control to avoid a collision between the host vehicle and an obstacle by allowing the host vehicle to deviate from a lane of the host vehicle, which is a lane on which the host vehicle is traveling, to an adjacent lane, which is a lane adjacent to the lane of the host vehicle, when the obstacle having a high probability of collision with the host vehicle is detected based on detected information by the forward direction detecting means.

[0012] The collision avoidance steering control device includes: an avoidance space determining means for determining whether or not a collision avoidance space exists that allows the host vehicle to enter the adjacent lane based on the information detected by the forward direction detecting means (S13); and a specific situation determining means for determining whether or not a current situation is a predetermined specific situation in which, based on environmental information about a portion around an edge of the adjacent lane on the opposite side of the host vehicle's lane, it is predicted that there is no moving object about to enter the adjacent lane from an area outside a host vehicle's road, which is a road on which the host vehicle is traveling (S14-S16).

[0013] Furthermore, the collision avoidance steering control means is configured to determine that an execution permission condition for executing the collision avoidance steering control is satisfied at least when the collision avoidance space is determined to exist by the avoidance space determining means and the current situation is determined to be the predetermined specific situation by the specific situation determining means.

[0014] In the above embodiment, the forward detection device detects a three-dimensional object and a white line (road marking line applied to a road) both in the area (ie, the front detection area) in front of the host vehicle and between the diagonally forward left direction of the host vehicle and the diagonally forward right direction of the host vehicle. The forward detection device may include the forward camera sensor.The collision avoidance steering control device (or the control unit) executes the collision avoidance steering control to avoid a collision between the host vehicle and the obstacle by making the host vehicle deviate from the lane of the host vehicle when the obstacle having a high probability of collision with the host vehicle is detected based on the information detected by the forward detection device.

[0015] When performing the above-mentioned collision avoidance steering control, it is necessary to ensure that no collision (secondary collision) occurs between the host vehicle and the other object (other than the obstacle). In view of this, the collision avoidance steering control device includes the avoidance space determination device and the specific situation determination device. The avoidance space determination device determines whether the collision avoidance space exists or not based on the information detected by the forward detection device. When the host vehicle enters (moves toward) the collision avoidance space, at least a part of the host vehicle enters the adjacent lane.

[0016] Meanwhile, the detection range of the forward detection device is limited to an area with a relatively narrow detection angle.

[0017] The detection ranges of the forward-facing camera sensor and the forward-facing radar sensor lie between the respective diagonal front-left direction of the host vehicle and a diagonal front-right direction of the host vehicle. Therefore, the movement of an object located in an area to the side of the host vehicle may not be easily detected.However, even if the detection range of the forward direction detection means is not wide enough, there may be a case where it can be predicted / determined that there is no moving object entering (or about to enter) the adjacent lane from the area outside the road of the host vehicle using the environmental information about a portion around an edge of the adjacent lane on the opposite side of the host vehicle's lane obtained by the forward direction detection means.

[0018] In view of the foregoing, the specific situation determining means determines whether or not a current situation is the predetermined specific situation in which it is predicted that there is no moving object about to enter the adjacent lane from an area outside the road of the host vehicle, based on the environmental information about the portion around an edge of the adjacent lane on the opposite side of the host vehicle's travel lane, the environmental information being included in the information detected by the forward direction detecting means. The environmental information may preferably be acquired by the forward direction camera sensor. The specific situation represents the situation of an area near the collision avoidance space.

[0019] The execution permission condition for executing the collision avoidance steering control is satisfied at least when the collision avoidance space is determined to exist by the avoidance space determining means, and the current situation is determined to be the predetermined specific situation by the specific situation determining means. Therefore, if it is determined that the collision avoidance space does not exist, the collision avoidance steering control is not executed (or is prohibited). If the current situation is not determined to be the predetermined specific situation, the collision avoidance steering control is also not executed (or is prohibited).Accordingly, the collision avoidance device of the present disclosure has a simple configuration and can, when necessary, make the vehicle deviate from the lane of the host vehicle to avoid the collision, while ensuring safety.

[0020] In some embodiments, the control unit is configured to determine that the current situation is the predetermined specific situation when it is determined based on the surrounding information that a roadside object that prevents a moving object from the area off-road of the host vehicle from entering the adjacent lane is present in the portion in the vicinity of the edge of the adjacent lane (S14).

[0021] The roadside object may consist of, for example, bushes, guardrails, or the like. When the roadside object is detected (or is present), a moving object cannot enter the adjacent lane from the off-road area of ​​the host vehicle. In view of the foregoing, in some embodiments, a specific situation is defined as a situation in which the roadside object is detected in the section surrounding (or near) the edge of the adjacent lane, wherein the roadside object prevents the moving object from entering the adjacent lane from the off-road area of ​​the host vehicle.

[0022] In some embodiments, the control unit is configured to determine that the current situation is the predetermined specific situation when it is determined based on the surrounding information that a road marking line (e.g., white line) applied (on the road of the host vehicle) to define the adjacent lane is detected in the portion in the vicinity of the edge of the adjacent lane, and that no object is detected in the vicinity of the detected road marking line (S15: Yes, S16: Yes).

[0023] If the road marking line (e.g. white line) is applied / formed at the edge of the host vehicle's road on which the host vehicle is traveling, it is unlikely that an object (e.g. the other vehicle) will suddenly enter the host vehicle's road. However, the other vehicle may enter the host vehicle's road, e.g. from the other road that meets the host vehicle's road. If the road marking line (e.g. white line) is applied / formed (continuously) at the edge of the host vehicle's road (i.e. the connecting part between the other road and the host vehicle's road), the other vehicle is expected to temporarily stop behind the road marking line. Therefore, if the other vehicle is not detected near the road marking line (e.g. white line), the host vehicle can safely move to the adjacent lane.In view of the above, in some embodiments, the predetermined specific situation is defined as a situation in which it is determined that a road marking line (e.g., white line) drawn (on the road of the host vehicle) for defining the adjacent lane is detected in the portion in the vicinity of the edge of the adjacent lane, and it is also determined that no object is detected in the vicinity of the detected road marking line.

[0024] In some embodiments, the control unit is configured to determine that the current situation is the predetermined specific situation when it is determined, based on the surrounding information, that a road marking line drawn on the road of the host vehicle to define the adjacent lane is detected in the portion in the vicinity of the edge of the adjacent lane, and that no object is detected in the vicinity of the detected road marking line (S15: Yes, S16: Yes), even if it is not determined that the roadside object is present in the portion in the vicinity of the edge of the adjacent lane (S14: No).

[0025] In some embodiments, the control unit is configured to first determine whether the current situation is a situation in which the roadside object is detected in the section around the edge of the adjacent lane, and to determine that the current situation is the specific situation in which the roadside object is detected in the section around the edge of the adjacent lane. Moreover, even if the roadside object is not detected in the section around the edge of the adjacent lane, the control unit is configured to determine that the current situation is the specific situation if the current situation is a situation in which the road marking line is detected in the section around the edge of the adjacent lane and no object is detected near the detected road marking line.Accordingly, the number of scenarios in which collision avoidance assistance is performed using autonomous steering is increased.

[0026] In some embodiments, a rearward radar sensor (51R, 51L) is added, configured to detect a target object approaching the vehicle in the adjacent lane from behind the vehicle. In other words, a detection device is added rearward of the vehicle to detect a vehicle behind the vehicle approaching the vehicle from behind the vehicle (50, 51R, 51L).

[0027] The control unit is configured to determine that the execution permission condition is met when, in addition to the first condition (S13: Yes) and the second condition (S14: Yes, S16: Yes), a third condition is met (S17: Yes), where the third condition is a condition that is met when the target object (e.g., behind the vehicle) is not detected by the reversing radar sensor. In other words, the collision avoidance steering control is executed when at least the first to third conditions are met.

[0028] In the above configuration, the rearward radar sensor or the rearward detection device is configured to detect a target object (the other vehicle, which is the rear vehicle following the host vehicle from the rear of the host vehicle) traveling in the adjacent lane and approaching the host vehicle from the rear of the host vehicle. A portion of a known blind spot monitoring / control system, known as one of the driving assistance systems, can be used for the rear vehicle detection device. The blind spot monitoring system is a system that notifies the driver of the presence of another vehicle located in the driver's blind spot and / or the presence of another vehicle that is predicted / expected to enter the driver's blind spot.

[0029] When performing collision avoidance steering control, attention must be paid to another vehicle approaching the host vehicle from the area behind the host vehicle. In view of the above, the control unit (or collision avoidance steering control device) confirms the following first to third conditions before performing collision avoidance steering control.

[0030] The first condition is met when it is determined that the collision avoidance space exists (by the avoidance space determining device).

[0031] The second condition is satisfied when the current situation is determined (by the specific situation determining means) as the predetermined specific situation.

[0032] The third condition is met when no target object (the other vehicle behind the host vehicle) approaching the host vehicle from the area behind the host vehicle is detected (by the rear-facing vehicle detection device).

[0033] Accordingly, the collision avoidance steering control can be performed more safely.

[0034] Note that, in the above description, in order to facilitate understanding of the present disclosure, the constituent elements or the like of the disclosure corresponding to those of the embodiments of the disclosure described later are denoted by reference numerals and / or symbols used in the embodiments in parentheses. However, the constituent elements of the disclosure are not limited to those in the embodiments defined by the reference numerals and / or symbols. Other objects, other features, and the associated advantages of the present disclosure will become more apparent from the following description of the embodiments of the disclosure, which is made with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic diagram of a collision avoidance assist device according to an embodiment of the present disclosure. Fig. 2 is a plan view of a host vehicle showing the detection angle ranges of a forward direction sensor and a rearward side direction radar sensor. Fig. 3 is a plan view of the carrier vehicle and an object for describing an overlap ratio. Fig. Figure 4 is a top view of the carrier vehicle and the object to describe the overlap ratio. Fig. Figure 5 is a plan view of the carrier vehicle and the object to describe the overlap ratio. Fig. Figure 6 is a flowchart illustrating a PCS control routine. Fig. 7 is a plan view of the host vehicle and the object for describing collision avoidance by autonomous steering within a lane of the host vehicle. Fig. 8A is a plan view of the host vehicle and another vehicle for describing detection angle ranges when a device has forward-side direction sensors. Fig. 8B is a plan view of the host vehicle and another vehicle for describing detection angle ranges when a device does not have the forward side direction sensors. Fig. 9 is a plan view of the carrier vehicle and another vehicle to describe a specific situation. Fig. 10 is a view through the front windshield of the carrier vehicle. Fig. 11 is a view through the front windshield of the carrier vehicle. Fig. 12 is a view through the front windshield of the carrier vehicle. DETAILED DESCRIPTION

[0035] A collision avoidance assist device (hereinafter sometimes referred to as "the present device") of a vehicle according to an embodiment of the present disclosure will be described with reference to the drawings.

[0036] The present device is applied to a vehicle, sometimes referred to as a “carrier vehicle” to distinguish it from other vehicles. As in Fig. As shown in Figure 1, the present device includes a driving assistance device (ECU 10), a meter device (ECU 20), an electric power steering (ECU 30), a brake (ECU 40), and a blind spot monitoring (ECU 50). Hereinafter, the electric power steering ECU 30 is referred to as "EPS ECU 30," and the blind spot monitoring ECU 50 is referred to as "BSM ECU 50."

[0037] An "ECU" is an abbreviation for electronic control unit. The ECUs described above are interconnected via a CAN (Controller Area Network) 100, so that any one of the ECUs can send and receive information to any other ECU. Each of the ECUs consists of a microcomputer with a CPU, a ROM, a RAM, a non-volatile memory, and an interface I / F as its main component. The CPU achieves various functions described later by executing instructions (i.e., programs / routines) stored in the memory (ROM). Some or all of these ECUs may be integrated into a single ECU.

[0038] A plurality of vehicle condition sensors 60 configured to detect vehicle conditions (driving conditions) of the host vehicle are connected to the CAN 100, and a plurality of vehicle operation condition sensors 70 configured to detect driving operation conditions of the host vehicle are also connected to the CAN 100. The vehicle condition sensors 60 include a vehicle speed sensor configured to detect / measure a vehicle speed (speed of the host vehicle), a longitudinal acceleration sensor configured to detect acceleration of the host vehicle in a longitudinal direction (front-rear), a lateral acceleration sensor configured to detect acceleration of the host vehicle in a transverse direction (left-right), and a yaw rate sensor configured to detect a yaw rate of the host vehicle.

[0039] The vehicle operating state sensors 70 include an accelerator operation amount sensor configured to detect an operation amount of an accelerator pedal, a brake operation amount sensor configured to detect an operation amount of a brake pedal, a brake switch configured to detect the presence or absence of operation of the brake pedal, a steering angle sensor configured to detect a steering angle, a steering torque sensor configured to detect a steering torque, and a shift position sensor configured to detect a shift lever position for a transmission.

[0040] Information (hereinafter referred to as "sensor information") acquired by the vehicle state sensors 60 and the vehicle operation state sensors 70 is transmitted to the CAN 100. Each of the ECUs can utilize the sensor information transmitted to the CAN 100 as needed. Note that the sensor information may be information acquired by a sensor connected to a specific one of the ECUs. In this case, the specific one of the ECUs transmits the sensor information obtained from the connected sensor to the CAN 100. For example, the steering angle sensor may be connected to the EPS ECU 30, which then transmits information about the steering angle detected by the steering angle sensor to the CAN 100 as sensor information. This may be applicable to the other sensors.It should also be noted that the sensor information can be exchanged through direct communication between the specific ECUs without using the CAN 100.

[0041] The driving assistance ECU 10 is a main control device for performing driving assistance control (or driving assistance control for assisting the driver in steering the host vehicle). The driving assistance ECU 10 is configured to perform collision avoidance assistance control as the driving assistance control device.

[0042] The collision avoidance assistance control is a control to: to alert the driver when an obstacle is detected in front of the host vehicle, where the obstacle is an object with a high probability of collision between the host vehicle and the object; and perform autonomous braking (control) and / or autonomous steering (control) when the probability of collision increases in order to avoid the collision.

[0043] Collision avoidance assist control is generally referred to as “PCS control (Pre-Crash Safety Control)” and is therefore sometimes referred to as “PCS control”.

[0044] The driving assistance ECU 10 may be configured to perform other driving assistance controls in addition to the PCS control. For example, the driving assistance ECU 10 may be configured to perform lane keeping assistance control to allow the host vehicle to travel along a center position of a traveling lane of the host vehicle, which is a traveling lane in which the host vehicle travels.

[0045] The driving assistance ECU 10 is connected to a forward direction (forward-facing range) camera sensor 11, a forward direction (forward-facing range) radar sensor 12, a buzzer 13, and a setting actuator 14.

[0046] As in Fig. As shown in Figure 2, the forward-facing camera sensor 11 is arranged at the upper portion of a windshield and in the interior cabin of the host vehicle. The forward-facing camera sensor 11 consists of a camera part (not shown) and an image processing part (not shown) configured to analyze the image data captured by the camera part. The camera part of the forward-facing camera sensor 11 is a monocular camera and captures an image of a scene (an area) in front of (or ahead of) the host vehicle. As shown in Fig. 2, the front-direction camera sensor 11 is placed or arranged on a longitudinal axis CL of a vehicle body of the host vehicle such that an optical axis of the camera part is parallel to the longitudinal axis CL of the vehicle body (or orthogonal to the right-left (or width / side) direction of the vehicle body). The forward-direction camera sensor 11 captures (ie, captures) an image from a forward-direction camera detection area FCA, which is a region between a (first) diagonally forward left direction of the vehicle body and a (first) diagonally forward right direction of the vehicle body in a plan view, every time a predetermined time elapses.

[0047] The image processing part of the forward camera sensor 11 is configured to detect a road marking line, such as a white or yellow line (for defining a lane), drawn on the road, and an object (3D (three-dimensional) object) located in front of the host vehicle based on the detected image, and to deliver / transmit information about it (i.e., white line information and 3D object information) to the driving assistance unit 10 every time the predetermined time elapses. The white line information includes information indicating a shape (e.g., a curvature) of the white line and information indicating a relative positional relationship in the road width direction between the white line and the host vehicle.The 3D object information includes information indicating the type and size of the detected 3D object located in front of the vehicle, as well as information indicating the relative positional relationship (both longitudinal and lateral) between the 3D object and the host vehicle. The type of the 3D object can be specified based on machine learning.

[0048] The forward radar sensor 12 is arranged in the center of a front end of the vehicle body and is configured to detect a 3D object located in front of the host vehicle. More specifically, as shown in Fig. As shown in Figure 2, the forward radar sensor 12 is arranged on the longitudinal axis CL of the vehicle body of the host vehicle such that a central axis of the radar wave emitted by the sensor 12 is parallel to the longitudinal axis CL of the vehicle body (or orthogonal to the width direction of the vehicle body). The forward radar sensor 12 is configured to detect the 3D object located within a forward radar detection area FRA, which is a range between a (second) diagonal front-left direction of the vehicle body and a (second) diagonal front-right direction of the vehicle body in a plan view.

[0049] The forward radar sensor 12 consists of a radar wave transmitting / receiving part (not shown) and a signal processing part (not shown). The radar wave transmitting / receiving part is configured to transmit a radar wave (i.e., an electrical wave referred to as a "millimeter wave") in a millimeter wave band. The 3D object (e.g., another vehicle, a pedestrian, a bicycle, a building, etc.) located within the forward radar detection range FRA reflects the transmitted millimeter wave. The radar wave transmitting / receiving part is configured to receive the reflected millimeter wave.The signal processing section of the forward radar sensor 12 is configured to obtain radar information indicating a distance between the 3D object and the host vehicle, a relative speed of the 3D object with respect to the host vehicle, a relative direction (orientation) of the 3D object with respect to the host vehicle, or the like based on a phase difference between the transmitted millimeter wave and the received millimeter wave, a time difference between a time point at which the millimeter wave is transmitted and a time point at which the reflected millimeter wave is received, or the like. The forward radar sensor 12 is configured to transmit the radar information (3D object information) to the driving assistance ECU 10 every time a predetermined time elapses.

[0050] The driving assistance ECU 10 synthesizes the 3D object information from the forward camera sensor 11 and the 3D object information from the forward radar sensor 12 to obtain more accurate 3D object information. Based on the white line information from the forward camera sensor 11, the driving assistance ECU 10 detects (specifies) the host vehicle's lane in which the host vehicle is traveling, as well as the adjacent lane adjacent to the host vehicle's lane (beside the host vehicle's lane).

[0051] Hereinafter, the forward-facing camera sensor 11 and the forward-facing radar sensor 12 are sometimes collectively referred to as the "forward-facing sensor." The 3D object information from the forward-facing camera sensor 11 and the 3D object information from the forward-facing radar sensor 12 are information about the area in front of the host vehicle and may sometimes be referred to as "forward-facing information."

[0052] The Fig. The buzzer 13 shown in Figure 1 is configured to receive a buzzer activation signal sent from the driving assistance ECU 10 to generate an alarm sound. The driving assistance ECU 10 is configured to send the buzzer activation signal to the buzzer 13 so that the buzzer 13 generates the alarm sound when the driving assistance ECU 10 needs to warn the driver.

[0053] The setting operating device 14 is an operating device with which the driver can set various parameters and is arranged, for example, on the steering wheel. The driving assistance ECU 10 is configured to receive a signal (setting signal) for setting the parameters from the setting operating device 14 and to perform various setting operations. For example, the setting operating device 14 is used to set an operating state of the driving assistance controller (e.g., the PCS controller) either to an operational state in which the driving assistance control is permitted to be executed, or to an inoperative state in which the driving assistance control is prohibited.

[0054] The meter ECU 20 is connected to a display (indicator or display device) 21, e.g., a multi-information display, arranged in front of a driver's seat. The display 21 is configured to display various information, including the vehicle speed, in addition to the measured values. For example, when the meter ECU 20 receives a display instruction corresponding to a driving assistance status from the driving assistance device ECU 10, the meter ECU 20 causes the display 21 to display a screen identified by the display instruction. Note that a head-up display (not illustrated) may be used as the display 21 instead of or in addition to the multi-information display. When using the head-up display, it is preferable to dedicate an ECU exclusively to the head-up display.

[0055] The EPS-ECU 30 is a controller for an electric power steering system and is connected to a motor driver 31. The motor driver 31 is connected to a steering motor 32, which is an actuator for the steering. The steering motor 32 is integrated into a steering mechanism (not shown) of the host vehicle. The EPS-ECU 30 is configured to detect the steering torque applied by the driver to a steering wheel (not shown) using the steering torque sensor attached to a steering shaft (not shown) and to control the motor driver 31 to drive the steering motor 32. When the steering motor 32 is driven as described above, a steering torque is applied to the steering mechanism to assist the driver's steering operation.

[0056] When the EPS-ECU 30 receives a steering instruction from the driving assistance ECU 10 via the CAN 100, the EPS-ECU 30 drives the steering motor 32 based on a control amount specified by the steering instruction to generate the steering torque. This steering torque, which is different from the steering torque for assisting the driver's steering operation described above, is a torque applied to the steering mechanism according to the steering instruction from the driving assistance ECU 10.

[0057] The brake ECU 40 is connected to a brake actuator 41 arranged in an unillustrated hydraulic circuit between an unillustrated master cylinder and a friction brake mechanism 42 of each wheel. The master cylinder pressurizes brake (working) fluid according to the pressing force of the brake pedal. The friction brake mechanism 42 consists of a brake disc 42a attached to each wheel and a brake caliper 42b attached to the vehicle body. The brake actuator 41 is configured to vary / regulate the oil pressure applied to an unillustrated wheel cylinder in the brake caliper 42b in response to an instruction sent from the brake ECU 40. The wheel cylinder is actuated by the oil pressure to press an unillustrated brake pad against the brake disc 42a, thereby generating a friction braking force.In this way, the brake ECU 40 controls the brake actuator 41 to control the braking force of the host vehicle.

[0058] The BSM-ECU 50 is a main controller of a blind spot monitoring system. The BSM-ECU 50 is connected to a rear-right radar sensor 51R, a rear-left radar sensor 51L, a right indicator 52R, and a left indicator 52L (see Fig. 2).

[0059] As in Fig. As shown in Figure 2, the rear-right radar sensor 51R is a radar sensor arranged / located at a rear-right corner of the vehicle body, and the rear-left radar sensor 51L is a radar sensor arranged / located at a rear-left corner of the vehicle body. The rear-right radar sensor 51R and the rear-left radar sensor 51L have the same configurations as the rear-left radar sensor 51L, except for their detection ranges. If the rear-right radar sensor 51R and the rear-left radar sensor 51L do not need to be distinguished from each other, each of them may be referred to as the "reverse radar sensor 51."

[0060] The backward radar sensor 51, similar to the forward radar sensor 12, is composed of an unillustrated radar wave transmitting / receiving part and an unillustrated signal processing part.

[0061] The rear-right radar sensor 51R is configured to emit a radar wave. A central axis of the radar wave emitted by the rear-right radar sensor 51R is parallel to a diagonally rearward right direction. The rear-right radar sensor 51R is configured to detect a 3D object located within a radar detection area RRRA that includes the central axis of the radar wave emitted by the rear-right radar sensor 51R and a predetermined angular range in plan view.

[0062] The rear-left radar sensor 51L is configured to emit a radar wave. A central axis of the radar wave emitted by the rear-left radar sensor 51L is parallel to a diagonal direction toward the rear left. The rear-left radar sensor 51L is configured to detect a 3D object located within a rear-left radar detection area RLRA, that is, an area including the central axis of the radar wave emitted by the rear-left radar sensor 51L and a predetermined angular range in plan view.

[0063] The reverse direction radar sensor 51 acquires information about a detected 3D object and sends it to the BSM-ECU 50. The information regarding a detected 3D object that the reverse direction radar sensor 51 receives is hereinafter referred to as “reverse direction information” and includes information indicating a distance between the 3D object and the host vehicle, a relative speed of the 3D object with respect to the host vehicle, a relative direction (orientation) of the 3D object with respect to the host vehicle, or the like.

[0064] Hereinafter, the 3D object detected by one of the forward direction sensors and the backward direction radar sensor 51 is sometimes referred to as a “target object”.

[0065] It should be noted that the Fig. 2 shows a detection angle range of the forward camera detection area FCA, the forward radar detection area FRA, the rear-right radar detection area RRRA, and the rear-left radar detection area RLRA, but not the detection distance of each of these areas. The detection distance of each of these areas is longer than that shown in Fig. 2 distance shown.

[0066] The right indicator 52R and the left indicator 52L are each devices that alert (warn) the driver. For example, the right indicator 52R is located on (or incorporated into) a right side mirror, and the left indicator 52L is located on (or incorporated into) a left side mirror. The right indicator 52R and the left indicator 52L have the same configuration. Hereinafter, if it is not necessary to distinguish between the right indicator 52R and the left indicator 52L, each of them may be referred to as "indicator 52."

[0067] The BSM-ECU 50 is configured to: determine whether or not “another vehicle at least a portion of which is located in the driver’s blind spot” is present based on the rearward direction information (ie, rearward / rearward surrounding information) transmitted from the rearward direction radar sensor 51; and to consider the “other vehicle, at least a part or section of which is determined by the driver’s blind spot” as an object to be paid attention to (or an object that the driver should notice).

[0068] In addition, the BSM-ECU 50 is configured to: determine whether or not there is another vehicle predicted / expected to enter the driver's blind spot within a predetermined period of time based on the reversing information sent from the reversing radar sensor 51; and to detect / consider “another vehicle that is predicted / expected to enter the driver’s blind spot within the specified time period” as the object to be watched for.

[0069] When it is determined that the object (the other vehicle) to be monitored is present, the BSM-ECU 50 turns on (or activates) the indicator 52 corresponding to a blind spot location (i.e., the right-side blind spot corresponding to the blind spot on the right side of the host vehicle, or the left-side blind spot corresponding to the blind spot on the left side of the host vehicle) where the object to be monitored is present. That is, the BSM-ECU 50 turns on the right indicator 52R when the object to be monitored is located in the right blind spot, and the BSM-ECU 50 turns on the left indicator 52L when the object to be monitored is located in the left blind spot. Therefore, the BSM-ECU 50 can alert the driver of the presence of the other vehicle that is not reflected in any of the mirrors, including the side mirrors and a rearview mirror. < PCS Control>

[0070] The PCS controller will be described next. The driving assistance ECU 10 is configured to determine whether the host vehicle has a high probability of colliding with a 3D object (target object) located in front of the host vehicle based on the traveling direction information sent from the forward direction sensor and the vehicle states detected by the vehicle state sensors 60. For example, the driving assistance ECU 10 determines whether the host vehicle has a high probability of colliding with the 3D object, assuming that the 3D object maintains its current moving state (e.g., a stopped state if the 3D object is a stationary object) and the host vehicle maintains its current moving state (driving state).When the driving assistance ECU 10 determines that the host vehicle is likely to collide with the 3D object based on the above determination result, the driving assistance ECU 10 detects / regards the 3D object as an obstacle.

[0071] When the driving assistance ECU 10 detects the obstacle, the driving assistance ECU 10 calculates (obtained by calculation) a time to collision TTC, which is a predicted time period from a current time to a collision time between the host vehicle and the obstacle. The time to collision TTC is calculated (obtained by calculation) based on the following equation (1) using a distance d between the host vehicle and the obstacle and a relative speed Vr of the obstacle with respect to the host vehicle. TTC=d / Vr

[0072] The time to collision (TTC) is used as an index value indicating the probability (degree) that the host vehicle will collide with the obstacle (or indicate an impending collision). The probability that the host vehicle will collide with the obstacle (i.e., the probability of collision) increases as the time to collision (TTC) decreases.

[0073] In the PCS control according to the present embodiment, the collision possibility is classified into two stages (i.e., a first stage and a second stage) based on the time to collision (TTC). In the first (first) stage, the driver is warned with the buzzer 13 and the display 21. In the second stage, where the collision possibility is higher than in the first stage, the braking control (autonomous braking) and / or the steering control (autonomous steering) are executed as collision avoidance assistance control.

[0074] The driving assistance ECU 10 determines that the possibility of a collision between the host vehicle and the obstacle has reached the first stage where the time to collision TTC has decreased to a threshold value for alerting TTCw. The driving assistance ECU 10 determines that the possibility of a collision between the host vehicle and the obstacle has reached the second stage when the time to collision TTC has further decreased to a threshold value for executing TTCa that is shorter / smaller than the threshold value for alerting TTCw (ie, TTCa < TTCw).

[0075] The driving assistance ECU 10 performs the collision avoidance assistance control by selectively executing either the autonomous braking or the autonomous steering according to an overlap ratio indicating a relative positional relationship in the width direction between the host vehicle and the obstacle when the possibility of a collision between the host vehicle and the obstacle has reached the second level.

[0076] The overlap ratio is described below. As in Fig. 3, the overlap ratio L (%) is an index value indicating a degree of overlap between the host vehicle V1 and the other vehicle V2 under the assumption that the host vehicle V1 collides with the other vehicle V2. In other words, the overlap ratio L (%) is calculated by dividing a length B by a width A of the host vehicle V1, as given by the following equation (2), where the length B is a length of a portion overlapped between the host vehicle V1 and the other vehicle V2 in the width direction. L=(B / A)−100(%)

[0077] In a Fig. In the example shown in Figure 4, the overlap ratio L is 100%.

[0078] As in Fig. 5, when the obstacle is a pedestrian whose position is represented by a point P, the overlap ratio L is defined such that the overlap ratio L is 100% when the position P is located on a center line in the width direction of the host vehicle V1, and the overlap ratio L is 0% when the position P is located on an extended line of one of the sides of the host vehicle V1. Namely, the overlap ratio L (%) is calculated by dividing a distance D between one of the sides of the host vehicle V1 and the position P in the width direction by half the width A of the host vehicle V1, as given by the following equation (3). L=[(D / (A / 2)])⋅100(%)=(2D / A)⋅100(%)

[0079] Autonomous braking is performed as collision avoidance assistance when the overlap ratio L is relatively high when the possibility of collision between the host vehicle and the obstacle has reached the second level, while autonomous steering (in a direction to reduce the overlap ratio L) is performed as collision avoidance assistance when the overlap ratio L is relatively low when the possibility of collision between the host vehicle and the obstacle has reached the second level.

[0080] For example, the driving assist ECU 10 executes autonomous braking as collision avoidance assist when the overlap ratio L is higher than a threshold value (overlap threshold) Lref. Specifically, the driving assist ECU 10 calculates (obtains by calculation) a target deceleration to avoid the collision between the host vehicle and the obstacle, and transmits the braking command including the obtained target deceleration to the brake ECU 40. The brake ECU 40 controls the brake actuator 41 to generate the friction braking force to the wheels so that the host vehicle is decelerated at the target deceleration.

[0081] Note that the driving assist ECU 10 may cancel autonomous braking when a driver's brake pedal operation is detected to give priority to the brake pedal operation. In this case, it is preferable to make the friction braking force generated according to the amount of brake pedal operation (or pressing force) larger than the braking force when there is no obstacle.

[0082] On the other hand, if the overlap ratio L is equal to or less than the threshold value Lref, the driving assistant ECU 10 determines whether or not there is a collision avoidance space (or a collision avoidance path) for avoiding the collision between the host vehicle and the obstacle in the direction that decreases the overlap ratio L, and executes the autonomous steering as the collision avoidance assistant if it is determined that there is a collision avoidance space. In this case, the driving assistant ECU 10 calculates a target steering angle (obtained by calculation) to make the host vehicle approach the collision avoidance space (or to make the host vehicle travel on the collision avoidance path), and transmits the steering instruction including the obtained target steering angle to the EPS ECU 30. The EPS ECU 30 controls the steering motor driver 32 so that an actual steering angle agrees with the target steering angle.This allows the host vehicle to move toward the collision avoidance zone. Note that the driver assistance ECU 10 can override autonomous steering when a driver's steering movement is detected, giving priority to the driver's steering movement.

[0083] In the present embodiment, the forward direction camera sensor 11 and the forward radar sensor 12 constitute the forward direction sensor. Thus, the present device cannot detect an object located near a position in a larger range with a wide angle. In other words, the present device has no problem in executing autonomous steering because the collision avoidance assistance is available when and only when the present device executes autonomous steering within the lane of the host vehicle (that is, when the collision avoidance space exists within the lane of the host vehicle). However, the front direction sensor is not sufficient to detect an object located in the adjacent lane. Therefore, the front direction sensor is not sufficient to make the vehicle deviate from the host vehicle's lane when the collision avoidance space exists in the adjacent lane.In other words, the front direction sensor cannot monitor a moving object (e.g., the other vehicle and the pedestrian) in front of the host vehicle over a large area. This complicates the execution of autonomous steering, which may cause the host vehicle to enter the adjacent lane if collision avoidance space exists in the adjacent lane. On the other hand, adding direction sensors to the front makes the device more complex and too expensive to install in low-cost vehicles.

[0084] In view of the above, the present device is configured to, when the collision avoidance space that causes the host vehicle to enter the adjacent lane has been detected using the forward direction sensor, determine whether the current situation is a specific situation described below based on the information from the forward direction sensor including information about an edge (or boundary) of the adjacent lane of a road. The specific situation is a situation in which it can be predicted that a moving object will not enter the adjacent lane that includes the collision avoidance space. By determining whether the current situation is the specific situation or not, the present device does not need to monitor an object located at a position on the side of the forward direction range of the host vehicle (a movement of an object). <lenkungs-pcs-steuerungsroutine>

[0085] The PCS control of the present device includes autonomous steering to avoid collisions. The following describes the processing of PCS control using autonomous steering. When an obstacle is detected in front of the vehicle, the driving assistant ECU 10 calculates the overlap ratio L with respect to the detected obstacle and executes a PCS control routine according to Fig. 6 if the overlap ratio L is smaller than the overlap ratio threshold Lref.

[0086] Note that, as described above, the driving assistance ECU 10 performs PCS control using autonomous braking when the overlap ratio L is greater than the overlap ratio threshold Lref. Furthermore, as described above, the driving assistance ECU 10 performs warning processing to warn the driver (while the time to collision TTC is equal to or shorter than the warning threshold TTCw), in addition to PCS control using autonomous braking or PCS control using autonomous steering.

[0087] When and after the driving assistance ECU 10 starts the steering PCS routine, the driving assistance ECU 10 calculates the time to collision (TTC) in step S11. Then, based on the forward direction information sent from the forward direction sensor, the driving assistance ECU 10 determines whether or not it is possible to avoid the collision by the autonomous steering within the lane of the host vehicle in step S12. In other words, the driving assistance ECU 10 determines whether or not the collision avoidance space for avoiding the collision between the host vehicle and the obstacle for the autonomous steering, which is located within the lane of the host vehicle and does not cause the host vehicle to deviate from the lane of the host vehicle, exists. Hereinafter, collision avoidance (control) using autonomous steering may sometimes be referred to as "collision avoidance steering (control)."

[0088] For example, as in Fig. As shown in Figure 7, if a space (i.e., a collision avoidance space) through which the host vehicle V1 can move / pass is detected / found between the obstacle and the right white line WL1, the collision avoidance path (which does not cause the host vehicle to deviate from the host vehicle's lane) can be found / drawn within the host vehicle's lane L1. In this case, it can be determined that collision avoidance steering control is possible within the host vehicle's lane L1.

[0089] Note that when both the right and left white lines are detected, the driving assistance ECU 10 detects / determines an area between the right and left white lines as the host vehicle's travel lane. When only one of the right and left white lines is detected, but a stationary roadside object is detected that is opposite to the detected right and left white lines in the width direction, the driving assistance ECU 10 detects / determines an area between the detected right and left white lines and the detected stationary roadside object as the host vehicle's travel lane.

[0090] When the driving assistance ECU 10 determines that the collision avoidance steering control is possible within the host vehicle's lane (S12: Yes), the driving assistance ECU 10 proceeds to step S18 and determines whether or not the time to collision TTC is equal to or less than / shorter than the threshold for executing TTCa.

[0091] If the time to collision TTC is greater than / longer than the threshold for executing TTCa (S18; No), the driving assistance ECU 10 returns to step S11. Thus, the above processes are repeated as long as the time to collision TTC is greater than / longer than the threshold for executing TTCa. Note that the driving assistance ECU 10 switches from the collision avoidance assist using autonomous steering to the collision avoidance assist using autonomous braking when the overlap ratio L becomes equal to or smaller than the overlap ratio threshold Lref while repeating the above processes. This may occur if the obstacle O moves during the repetition of the above processes.

[0092] If the driving assistance ECU 10 determines that it is not possible to avoid the collision by the autonomous steering within the lane of the host vehicle (S12: No), the driving assistance ECU 10 proceeds to step S13.

[0093] In step S13, the driving assistance ECU 10 determines, based on the information from the forward direction sensor, whether or not a space exists (collision avoidance space exists) in the adjacent lane adjacent to the host vehicle's lane. In other words, the driving assistance ECU 10 determines whether or not an object with which there is a possibility of a re-collision (second collision) with the host vehicle exists in a space into which the host vehicle enters when the host vehicle deviates from the host vehicle's lane through collision avoidance steering control. For example, the driving assistance ECU 10 determines that such a space (collision avoidance space) does not exist (does not exist) in the following cases: ▪ A case where another vehicle that has the potential to cause the second collision is in the adjacent lane. ▪ A case where the road (host vehicle road) on which the host vehicle is traveling is double-lane (i.e., the host vehicle road has only one lane in one direction in which the host vehicle is moving (namely, a lane for traffic), so there is no adjacent lane).

[0094] Hereinafter, the adjacent lane refers to a lane into which the vehicle enters due to the collision avoidance steering control (i.e., a lane into which the host vehicle is steered due to the collision avoidance assistance with the help of the autonomous steering).

[0095] If the driving assistance ECU 10 determines that the collision avoidance space in the adjacent lane is not available (does not exist) (S13: No), the driving assistance ECU 10 temporarily terminates the steering PCS control routine. In this case, collision avoidance assistance with autonomous steering is not performed. After a predetermined period of time has elapsed, the driving assistance ECU 10 restarts the steering PCS control routine.

[0096] On the other hand, if the driving assistance ECU 10 determines that the collision avoidance space exists in the adjacent lane (S13: Yes), the driving assistance ECU 10 proceeds to step S14. In step S14, the ECU 10 determines, based on the information from the front sensor, whether or not the roadside object is detected on the adjacent lane side with respect to the host vehicle (e.g., on the right side if the adjacent lane is to the right of the host vehicle, and on the left side if the adjacent lane is to the left of the host vehicle). The roadside object is an object placed on a roadside to prevent a moving object (e.g., a bicycle, a vehicle, a pedestrian, etc.) from entering the road (on which the host vehicle is traveling) from an area outside the road (on which the host vehicle is traveling), including shrubbery and guardrails.If the roadside object is detected on the adjacent lane side (or toward the adjacent lane) with respect to the host vehicle, a position of the detected roadside object is determined / considered as the edge of the host vehicle road on the adjacent lane side.

[0097] In step S14 described above, the driving assistance ECU 10 makes the determination based on the information transmitted from the forward-facing camera sensor 11 among the forward-facing sensors, but may also make the determination based on the information transmitted from the forward-facing camera sensor 11 and the forward-facing radar sensor 12.

[0098] If, for example, as shown in an example in Fig. 8A, a comparative driving assistance system has the radar sensors 200R and 200L arranged at the front right corner and the front left corner, respectively, in addition to the front direction sensor, the comparative driving assistance system has a forward direction detection range that is wider in the width direction than the forward direction detection range of the driving assistance system of the present embodiment. Fig. In FIG. 8A, the reference symbol "FLRA" indicates a detection angle range of the front right-side direction sensor 200R, and the reference symbol "FRRA" indicates a detection angle range of the front left-side direction sensor 200L. Accordingly, the comparative driving assistance system with the front side radar sensors 200R and 200L can detect an object (e.g., the other vehicle V2) that is about to enter the adjacent lane L2 from a side area (in the lateral direction). Thus, the comparative driving assistance system performs collision avoidance steering control when this object is not detected, so that a second collision would not occur.Furthermore, even if the comparative driving assistance system detects the object about to enter the adjacent lane L2 from a side area (in the lateral direction), the comparative driving assistance system can determine whether or not there is no possibility of a second collision based on a relative position of the object with respect to the host vehicle V1 and a relative speed of the object with respect to the host vehicle V1 when performing collision avoidance steering control to deviate the host vehicle V1 from the lane of the host vehicle to the adjacent lane. In this way, the comparative driving assistance system can perform collision avoidance steering control while avoiding the second collision.

[0099] However, developing a system for detecting / sensing an object using the 200R and 200L forward-facing radar sensors is expensive and time-consuming. Furthermore, the comparative driver assistance system using the 200R and 200L forward-facing radar sensors requires a large amount of memory in the control unit and increases the computational load on the control unit.

[0100] In view of the above, the present apparatus according to the embodiment of the present disclosure has the same configuration (ie, a configuration including the front camera sensor 11 and the front radar sensor 12 and without front side radar sensors) as the typical collision avoidance assist apparatus, but is configured to determine whether or not the roadside object has been detected at the position to the side of the adjacent lane, so that it is capable of detecting a case where it is predicted that there is no object (e.g., the other vehicle) likely to enter the adjacent lane from the area off the road of the host vehicle.

[0101] For example, the present device has, as shown in Fig. 8B, the detection angle ranges (FRA, FCA) are relatively narrow, and therefore, the other vehicle V2, which is located away from the collision avoidance space in the lateral (width) direction, cannot be detected with the forward direction sensor. However, the present device can detect the roadside object X located on the side of the adjacent lane L2 using the forward direction sensor. The roadside object X is an object adjacent to (on the side of) the collision avoidance space. When the roadside object X is detected, it can be predicted / estimated that a moving object (e.g., the other vehicle V2) will not enter the adjacent lane L2 from outside the roadside object X (via the roadside object X).

[0102] If the driving assistance ECU 10 determines that the roadside object is located on the adjacent lane side (S14: Yes), the driving assistance ECU 10 proceeds to step S17. If the driving assistance ECU 10 determines that the roadside object is not located on the adjacent lane side (S14: No), the driving assistance ECU 10 proceeds to step S15.

[0103] Fig. 10 shows a scene in which an obstacle O is detected in front of the host vehicle while the host vehicle is traveling in the left lane LL. In this example, a collision avoidance space is detected in the right lane LR (in the same traffic as the left lane LL) and a roadside object X (e.g., a guardrail X) is detected on the roadside on the right lane LR side. Therefore, in this example, the driving assistance ECU 10 makes a "Yes" determination in step S14.

[0104] Fig. 11 shows a scene in which an obstacle O is detected in front of the host vehicle while the host vehicle is traveling in the right lane LR. In this example, a collision avoidance space is detected in the left lane LL (in the same traffic as the right lane LR) and a roadside object X (e.g., bushes X) is detected on the roadside on the left lane LL side. Therefore, the driving assistance ECU 10 also makes a "Yes" determination in step S14 in this example.

[0105] If the driving assistance ECU 10 determines that the roadside object is not on the adjacent lane side (S14: No), the driving assistance ECU 10 proceeds to step S15 and determines whether or not there is a white line on the adjacent lane side based on the information transmitted from the forward camera sensor 11. Note that the white line present on the adjacent lane side does not mean a boundary line between the host vehicle's lane and the adjacent lane, but a white line that is away from the boundary line (that is, a line that defines the adjacent lane together with the boundary line). The white line present on the adjacent lane side to be detected can be any type of lines (e.g., a continuous solid line or a broken line).When the white line present on the adjacent lane side is detected, the driving assistance ECU 10 regards the white line as an edge of the road of the host vehicle on the adjacent lane side.

[0106] Fig. For example, Fig. 9 shows a case where another road R2 (hereinafter referred to as connected road R2) intersects with a road R1 (hereinafter referred to as host vehicle road R1) on the adjacent lane L2 side (which is adjacent to host vehicle lane L1). The connected road R2 may be a road that connects the host vehicle road R1 to a facility. In this example, white lines WL1, WL2, and WL3 are plotted on the host vehicle road R1. Since the host vehicle road R1 is a priority road with respect to the connected road R2, the white line WL2 is continuously plotted at a position where the host vehicle road R1 and the connected road R2 are connected.

[0107] When the other vehicle V2 is about to enter the host vehicle's road R1 from the connected road R2, the other vehicle V2 stops behind the white line WL1 before entering the host vehicle's road R1. Therefore, when the white line WL2 is detected on the adjacent lane L2 side with respect to the host vehicle V1 and no object is detected near the white line WL2, it can be predicted that no moving object will enter the adjacent lane L2 from an area outside the host vehicle's road R1 while the host vehicle V1 is caused to enter the adjacent lane L2 by the collision avoidance steering control.

[0108] If the driving assistance ECU 10 determines that the white line on the adjacent lane side is detected (S15: Yes), the driving assistance ECU 10 proceeds to step S16 and determines whether or not there is a target object (e.g., another vehicle, a bicycle, a pedestrian, or the like) near the detected white line on the adjacent lane side based on the forward direction information transmitted from the forward direction sensor. The determination in step S16 is made using the forward direction information transmitted from both the forward direction camera sensor 11 and the front radar sensor 12.

[0109] If the driving assistance ECU 10 determines that there is no target object near the detected white line on the adjacent lane side (S16: Yes), the driving assistance ECU 10 proceeds to step S17.

[0110] In contrast, the driving assistance ECU 10 temporarily terminates the PCS steering control routine when: the driving assistance ECU 10 determines that the white line on the side of the adjacent lane is not detected (S15: No); or the driving assistance ECU 10 determines that a target object is near the detected white line even when the white line is detected (S16: No).

[0111] In both of the above cases, collision avoidance assistance using autonomous steering is not performed. After the specified time period has elapsed, the driver assistance ECU 10 restarts the steering PCS control routine.

[0112] Fig. 12 shows a scene in which an obstacle O is detected in front of the host vehicle while the host vehicle is traveling in the center lane LC between the right lane LR and the left lane LL. In this example, a collision avoidance space is detected in the left lane LL (on the collision avoidance direction side), and a white line WL in the left lane LL is continuously detected (a white line WL that continues is detected). Furthermore, in this example, a target object (the other vehicle V2) is detected near the white line WL adjacent to the collision avoidance space. Therefore, in this example, the driving assistance ECU 10 makes a "No" determination in step S16.

[0113] In step S17, the drive assistance ECU 10 determines whether or not a target object (the other vehicle) is approaching from behind the host vehicle. In this case, the drive assistance ECU 10 receives the information from the reverse radar sensor 51 via the BSM ECU 50 to make the determination based on the obtained information.

[0114] For example, the driving assistance ECU 10 determines that no target object from the area behind the host vehicle is approaching the host vehicle if: no target object is detected / detected by the reverse radar sensor 51; or the driving assistance ECU 10 determines, based on the relative position of the target object with respect to the host vehicle and the relative speed of the target object with respect to the host vehicle, that there is no possibility of a second collision between the host vehicle and the target object approaching the host vehicle from behind the host vehicle even if the target object is detected / sensed by the rearward radar sensor 51.

[0115] In addition to or instead of the above configuration, the driving assistance ECU 10 may determine that a target object is approaching the host vehicle from the area behind the host vehicle when the BSM-ECU 50 has detected the object to be observed (the other vehicle) in the adjacent lane (in other words, when the BSM-ECU 50 activates the indicator 52).

[0116] The driving assistance ECU 10 temporarily terminates the steering PCS control routine when the driving assistance ECU 10 determines that a target object is approaching the host vehicle from the area behind the host vehicle (S17: No). In this case, collision avoidance assistance using autonomous steering is not executed. After the specified time has elapsed, the driving assistance ECU 10 restarts the steering PCS control routine.

[0117] In contrast, the driving assistance ECU 10 proceeds to step S18 when the driving assistance ECU 10 determines that no target object is approaching the host vehicle from the area behind the host vehicle (S17: Yes).

[0118] In step S18, the driving assistance ECU 10 determines whether or not the time to collision TTC is equal to or less than the threshold for executing TTCa, and returns to step S11 when the time to collision TTC is greater than the threshold for executing TTCa to repeat the above processes.

[0119] If the time until TTCa is executed is equal to or less than the threshold for TTCa execution while repeating the above-described processes (S18: Yes), the driving assistance ECU 10 proceeds to step S19 and executes the collision avoidance steering control (that is, it executes the control for collision avoidance assistance using autonomous steering). In this case, the driving assistance ECU 10 calculates the target steering angle for allowing the host vehicle to move toward the collision avoidance space (or for allowing the host vehicle to travel on the collision avoidance path) and transmits the steering instruction including the target steering angle to the EPS ECU 30. The EPS ECU 30 controls the steering motor driver 32 so that an actual steering angle coincides with the target steering angle. This allows the host vehicle to move toward the collision avoidance space.

[0120] The driving assistance ECU 10 terminates the steering PCS control routine after the collision avoidance steering control is completed. This can avoid a collision of the host vehicle with the obstacle (or mitigate damage / effect of the collision between the host vehicle and the obstacle).

[0121] The collision avoidance assist device (the present device) of the embodiment according to the present disclosure has been described. The present device determines whether or not the collision avoidance space exists in the adjacent lane when the present device cannot avoid the collision by autonomous steering within the lane of the host vehicle. If it is determined that the collision avoidance space exists in the adjacent lane, the present device determines whether or not the current situation is a specific situation in which it can be predicted that no object will enter the adjacent lane from the area outside the road of the host vehicle. It is determined when the specific situation is detected: A first case is met if the roadside object was detected on the side of the adjacent lane; and / or a second case is met when the white line was detected on the side of the adjacent lane and no target object was detected near the detected white line.

[0122] The present apparatus is configured to execute the collision avoidance assistance using the autonomous steering that makes the host vehicle enter the adjacent lane at least when it is determined that the collision avoidance space exists on the adjacent lane and the current situation is determined as the specific situation.

[0123] In other words, a condition that is satisfied when at least one of the first and second conditions described below is satisfied is used as an execution permission / permission condition for executing the collision avoidance steering control that causes the host vehicle to enter the adjacent lane to avoid the collision. The first condition is a condition that is satisfied when it is determined that the collision avoidance space exists in the adjacent lane. The second condition is a condition that is satisfied when it is determined that the current situation is the specific situation.The present apparatus is configured to execute the collision avoidance steering control that makes the host vehicle enter the adjacent lane when the above execution permission / permission condition is satisfied and when it is determined that no target object from the area behind the host vehicle approaches (approaches) the host vehicle.

[0124] Despite the fact that the present device uses only the forward-direction camera sensor 11 and the forward-direction radar sensor 12 as the forward-direction sensor, the present device can perform collision avoidance assistance to ensure safety by causing the host vehicle to deviate from the host vehicle's lane and enter the adjacent lane. Consequently, the present device remains as simple as the known typical collision avoidance assistant and can expand the scenarios in which collision avoidance assistance is performed using autonomous steering. The present device maintains low cost.

[0125] Furthermore, according to the present device, the collision avoidance steering control that causes the host vehicle to enter the adjacent lane is performed only when it is determined that no target object is approaching the host vehicle from the area behind the host vehicle when the current situation is determined as the specific situation. Therefore, the collision avoidance control can be performed more safely.

[0126] It should be noted that the rear-right radar sensor 51R and the rear-left radar sensor 51L are used as sensors for detecting other vehicles approaching the host vehicle from behind the host vehicle. However, the radar sensors 51R and 51L are also used by the BSM system. Furthermore, the BSM system is a widely used driver assistance system in typical vehicles. Therefore, with the radar sensors 51R and 51L, the present device does not need to be expensive or complicated.

[0127] The collision avoidance assist device according to the present disclosure is not limited to the above-described embodiment, but various modifications are possible in view of the object of the present disclosure.

[0128] For example, in the above embodiment, the current situation is determined as the specific situation when either the first case described above or the second case described above is found, but the current situation may be determined as the specific situation when only one of the two cases is found.

[0129] Furthermore, the above embodiment may be configured to execute the collision avoidance assistance using the autonomous brake when any of the following cases is determined.

[0130] A case where it is determined that there is no collision avoidance space on the adjacent lane (S13: No).

[0131] A case where it is determined that the present situation is not the specific situation (S15, S16: No).

[0132] A case where it is determined that the other vehicle approaching the host vehicle from the area behind the host vehicle is present even if it is determined that the current situation is the specific situation (S17: No).

[0133] A driving assistance ECU determines that a current situation is a specific situation in which an object is predicted not to enter an adjacent lane from an area outside a road on which a host vehicle is traveling when a roadside object is detected at a portion surrounding an edge of the adjacent lane and / or when a white line drawn to define the adjacent lane is detected at the portion surrounding the edge of the adjacent lane and no object is detected near the detected white line. The driving assistance ECU does not perform steering control to avoid a collision, and the vehicle's steering control allows entry into the adjacent lane unless it is determined that the current situation is the specific situation.

Claims

[1] Collision avoidance assistance device for a vehicle, comprising: a forward-facing camera sensor configured to capture an image of a forward-facing camera detection area to obtain forward-facing camera sensor information, wherein the forward-facing camera detection area is an area between a diagonal front-left direction of the vehicle and a diagonal front-right direction of the vehicle; a forward radar sensor configured to obtain forward radar sensor information about an object located in a forward radar detection range, wherein the forward radar detection range is a range between a diagonal front-left direction of the vehicle and a diagonal front-right direction of the vehicle; and a control unit configured to perform collision avoidance steering control based on the forward camera sensor information to make the vehicle move into a collision avoidance space to avoid a collision between the vehicle and an obstacle when it is determined based on forward radar sensor information that an object exists as the obstacle that is highly likely to collide with the vehicle, wherein the control unit is configured to: determine, based on the forward camera sensor information and the forward radar sensor information, whether or not a first condition is satisfied, the first condition being a condition that is satisfied when it is determined that a specific space exists as a collision avoidance space, the specific space overlapping with a neighboring lane adjacent to a lane of the host vehicle on which the vehicle is traveling; based on environmental information about a portion in the vicinity of an edge of the adjacent lane on the opposite side of the host vehicle's lane, the environmental information being included in the forward camera sensor information and / or the forward radar sensor information, to determine whether or not a second condition is satisfied, the second condition being a condition that is satisfied when a current situation is a predetermined specific situation in which it is predicted that there is no object about to enter the adjacent lane from an area outside a road of the host vehicle, which is a road on which the host vehicle is traveling; and perform the collision avoidance steering control to make the vehicle move into the specific space when it is determined that an execution permission condition is satisfied, wherein the execution permission condition is a condition that is satisfied when at least both the first condition and the second condition are determined to be satisfied. [2] The collision avoidance assist device according to claim 1, wherein the control unit is configured to determine that the current situation is the predetermined specific situation when it is determined, based on the surrounding information, that a roadside object that prevents a moving object from the area outside the road of the host vehicle from entering the adjacent lane is present in the portion in the vicinity of the edge of the adjacent lane. [3] The collision avoidance assist device according to claim 1, wherein the control unit is configured to determine that the current situation is the predetermined specific situation when it is determined based on the surrounding information that a road marking line drawn on the road of the host vehicle to define the adjacent lane is detected in the portion in the vicinity of the edge of the adjacent lane, and that no object is detected in the vicinity of the detected road marking line. [4] The collision avoidance assist device according to claim 2, wherein the control unit is configured to determine that the current situation is the predetermined specific situation when it is determined, based on the surrounding information, that a road marking line drawn on the road of the host vehicle to define the adjacent lane is detected in the portion in the vicinity of the edge of the adjacent lane, and that no object is detected in the vicinity of the detected road marking line even if it is not determined that the roadside object exists in the portion in the vicinity of the edge of the adjacent lane. [5] A collision avoidance assist device according to any one of claims 1 to 4, further comprising a reverse radar sensor configured to detect a target object approaching the vehicle on the adjacent lane from an area behind the vehicle, and where the control unit is configured to determine that the execution permission condition is satisfied when a third condition is satisfied in addition to the first condition and the second condition, wherein the third condition is a condition that is satisfied when the target object is not detected by the rearward radar sensor.

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