Driving assistance device, vehicle, driving assistance method, and recording medium

Abstract

The present invention performs driving assistance control at appropriate times. The driving assistance device includes: a surrounding information acquisition device (11, 12) for acquiring surrounding information; a steering information acquisition device (15) for acquiring steering information; and a control unit (10) for performing driving assistance control including at least one of left and right turn deceleration assist control and left and right turn warning control when a predetermined first execution condition is met. When the premise condition is met that an intersection is detected based on surrounding information and the steering information determines that the driver is performing a steering operation, the control unit determines whether the first execution condition is met based on the steering operation being performed and the driving lane arrow information or the adjacent lane arrow information stored in the storage device as road surface arrow information of the driving lane or as road surface arrow information of the adjacent lane.

Description

Technical Field

[0001] The present invention relates to a driving assistance device, vehicle, driving assistance method, and recording medium capable of performing driving assistance controls including pre-turn deceleration assist control and / or pre-turn warning control, wherein the pre-turn deceleration assist control assists the vehicle in decelerating before turning left or right at an intersection, and the pre-turn warning control warns the driver of the vehicle before turning left or right at an intersection. Background Technology

[0002] In recent years, research has led to the development of driver assistance control technologies that assist in decelerating a vehicle to a predetermined target speed before making left or right turns at intersections. Driver assistance control includes at least one of left / right turn deceleration assist control and left / right turn warning control. Left / right turn deceleration assist control automatically applies braking force to the vehicle in a manner that matches the vehicle's deceleration to a target deceleration, thereby assisting in decelerating the vehicle before making left or right turns at intersections. Left / right turn warning control alerts the driver, thereby prompting the driver to decelerate before making left or right turns at intersections.

[0003] For example, Patent Document 1 discloses a driving assistance device configured to issue an alarm before the vehicle enters the intersection if the vehicle's speed exceeds a prescribed speed (the speed at which a vehicle can safely turn at the intersection) before the vehicle makes a left or right turn at the intersection.

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: Japanese Patent Application Publication No. 2011-129013 Summary of the Invention

[0007] The driving assistance device can be configured to, for example, determine whether the vehicle intends to turn left or right at an intersection based on a direction indicator switch (a switch capable of detecting the operation status of the turn signal stalk) and road surface arrow markings on the driving lane (the lane in which the vehicle is traveling), and execute the aforementioned driving assistance control if there is an intention to turn left or right. Specifically, the driving assistance device can be configured to determine that there is an intention to turn left or right if the direction corresponding to the operation status of the turn signal stalk detected by the direction indicator switch (i.e., the right or left direction) is included in the drivable direction of travel indicated by the road surface arrow markings on the driving lane.

[0008] However, according to this configuration, the timing of executing driver assistance control may be delayed. For example, suppose a vehicle intends to turn left or right at an intersection after changing lanes, and the turn signal is activated before the lane change. In this case, it is desirable to execute driver assistance control before the lane change so that the vehicle can appropriately decelerate to the target speed before turning left or right at the intersection. However, the driving assistance device determines whether the vehicle intends to turn left or right based on the road arrow markings of the driving lane. Therefore, if the road arrow markings of the driving lane cannot be recognized (typically, if the road arrow markings are rubbed, or if other vehicles are on the road arrow markings), it is impossible to properly determine whether there is an intention to turn left or right. In addition, if the road arrow markings of the driving lane only contain straight arrows, since the direction corresponding to the operation state of the turn signal is not included in the traversable direction (straight direction) of the road arrow markings, it will be determined that there is no intention to turn left or right. In these cases, the driving assistance device determines whether there is an intention to turn left or right only at the point when it recognizes the road arrow markings of the new driving lane after the lane change, therefore, the timing of executing driver assistance control may be delayed. This is particularly noticeable when the lane after the lane change is a dedicated right-turn lane or a dedicated left-turn lane.

[0009] This invention was made to address the aforementioned problems. Specifically, one objective of this invention is to provide a technology capable of performing driver assistance control at appropriate times.

[0010] The driving assistance device based on the present invention (hereinafter also referred to as the "device of the present invention") includes:

[0011] The surrounding information acquisition device (11, 12) is capable of acquiring road markings and information related to intersections existing in the area ahead as surrounding information, wherein the area ahead includes the road surface in front of the vehicle.

[0012] Steering information acquisition device (15), which is capable of acquiring information including whether the driver of the vehicle has made steering operations as steering information; and

[0013] A control unit (10) having a storage device, the control unit (10) being configured to,

[0014] When an intersection is detected based on the surrounding information (step 905: Yes), and a road surface arrow mark is detected on the lane in which the vehicle is traveling (i.e., the driving lane) or on a lane adjacent to the driving lane (i.e., the adjacent lane) (step 1010: Yes), for each lane, information including the road surface arrow mark and the permissible direction of travel indicated by it, i.e., road surface arrow information, is associated with the detected intersection and stored in the storage device (step 1020).

[0015] If the first execution condition, including the detection of an intersection based on the surrounding information, is met, driver assistance control is executed, including at least one of left / right turn pre-turn deceleration assist control and left / right turn pre-turn warning control. The left / right turn pre-turn deceleration assist control automatically applies braking force to the vehicle in a manner that matches the vehicle's deceleration to a target deceleration, thereby assisting the vehicle in decelerating to a predetermined target speed before making a right or left turn at the detected intersection. The left / right turn pre-turn warning control alerts the driver, thereby prompting the driver to decelerate before making a right or left turn at the detected intersection.

[0016] If the prerequisite condition is met (step 915: yes) when an intersection is detected based on the surrounding information and the driver is determined to be performing a steering operation based on the steering information, it is determined whether the first execution condition is met (step 925, step 950) based on the steering operation being performed and the driving lane arrow information stored in the storage device as the driving lane or the adjacent lane arrow information as the adjacent lane.

[0017] In the device of this invention, the determination of whether the first execution condition (the execution condition for driver assistance control) is met is based not only on the driving lane arrow information but also on the adjacent lane arrow information. Therefore, even if the first execution condition is determined to be unmet based on the driving lane arrow information, it is still possible to determine whether the first execution condition is met based on the adjacent lane arrow information. Therefore, compared to a configuration that determines the condition solely based on the driving lane arrow information, it is less likely to experience a delay in determining whether the first execution condition is met, resulting in driver assistance control being executed at the appropriate time.

[0018] In one aspect of the invention, the control unit (10) is configured to,

[0019] In the first case where the precondition is met and the driving lane arrow information is stored in the storage device (step 920: Yes), when the first direction condition is met (step 925: Yes), it is determined that the first execution condition is met, wherein the first direction condition is met when the direction corresponding to the steering operation being performed is included in the drivable direction of the driving lane indicated by the driving lane arrow information.

[0020] If, under the following preconditions, the driving lane arrow information is not stored in the storage device (step 920: No) or the first direction condition is not met (step 925: No), and the adjacent lane arrow information is stored in the storage device (step 935: Yes, step 940: Yes), then when the second direction condition is met (step 950: No), the first execution condition is determined to be met, wherein the second direction condition is met when the direction corresponding to the currently performed steering operation is included in the drivable direction of the adjacent lane indicated by the adjacent lane arrow information and the drivable direction does not include a straight-ahead direction.

[0021] If the second directional condition is not met (step 945: No, step 950: Yes), it is determined that the first execution condition is not met.

[0022] When the first directional condition is met, there is a high probability that the vehicle intends to turn left or right at the intersection (left-right turning intention). Therefore, by determining that the first execution condition is met when the first directional condition is met, the control can be appropriately executed when driver assistance control is required.

[0023] When the second directional condition is met, the adjacent lane is either a dedicated right-turn lane or a dedicated left-turn lane. Therefore, there is a high probability that the vehicle intends to turn left or right after changing lanes to that adjacent lane. Thus, by determining that the first execution condition is met even when the second directional condition is met, the control can be appropriately executed when driver assistance control is required.

[0024] On the other hand, when the second directional condition is not met because the direction corresponding to the steering operation is not included in the drivable direction of the adjacent lane, the vehicle is highly likely to only have the intention to change lanes (lane change intention) (i.e., not the intention to turn left or right). Furthermore, when the direction corresponding to the steering operation is included in the drivable direction of the adjacent lane but that drivable direction also includes a straight-ahead direction, it is difficult to determine whether the vehicle intends to turn left or right after changing lanes or only has the intention to change lanes. Therefore, by determining that the first execution condition is not met in these cases, unnecessary operation of the driver assistance control can be suppressed.

[0025] In this case, the control unit (10) is configured to,

[0026] Furthermore, if a second specified execution condition is met, including the detection of an intersection based on the surrounding information, the system can execute at least one of two mild driving assistance controls: mild deceleration assist control before left and right turns and mild warning control before left and right turns. Compared to the standard deceleration assist control, the mild deceleration assist control before left and right turns reduces the degree to which the vehicle decelerates to the target speed. Similarly, the mild warning control before left and right turns reduces the degree to which it alerts the driver.

[0027] In the second case (step 935: Yes, step 940: Yes), if the direction corresponding to the steering operation being performed is included in the drivable direction of the adjacent lane indicated by the adjacent lane arrow information and the drivable direction includes a straight direction, thus the second direction condition is not met (step 950: Yes), the second execution condition is determined to be met.

[0028] When the direction corresponding to the steering operation is included in the travel direction of the adjacent lane, but that travel direction also includes the straight-ahead direction, it is difficult to determine whether the vehicle intends to turn left or right after changing lanes, or simply intends to change lanes. Therefore, by implementing mild driver assistance control instead of full-range driver assistance control in such situations, it is possible to decelerate the vehicle to a certain extent before making a lane change if the vehicle intends to turn left or right after changing lanes, and on the other hand, to reduce the degree of unnecessary deceleration felt by the driver if the vehicle only intends to change lanes.

[0029] In one aspect of the invention, the control unit (10) is configured to,

[0030] Furthermore, if a second specified execution condition is met, including the detection of an intersection based on the surrounding information, the system can execute at least one of two mild driving assistance controls: mild deceleration assist control before left and right turns and mild warning control before left and right turns. Compared to the standard deceleration assist control, the mild deceleration assist control before left and right turns reduces the degree to which the vehicle decelerates to the target speed. Similarly, the mild warning control before left and right turns reduces the degree to which it alerts the driver.

[0031] In the third case where the prerequisite is met and neither the driving lane arrow information nor the adjacent lane arrow information is stored in the storage device (step 935: No), it is determined that the second execution condition is met.

[0032] In the third scenario, the lane arrow information is not stored in the control unit's storage device. This is because, during the period from the first detection of any intersection to the current moment, the lane arrow markings may become unrecognizable due to the presence of other vehicles or friction. Therefore, the direction corresponding to the steering operation may actually be included in the drivable direction of the lane. In other words, the vehicle may intend to turn left or right in the lane. Therefore, by performing mild driver assistance control in the third scenario, it is possible to slow the vehicle to a certain extent when the vehicle intends to turn left or right in the lane, and on the other hand, to reduce the degree of unnecessary deceleration felt by the driver when the vehicle does not have such an intention (in other words, only an intention to change lanes).

[0033] In one aspect of the invention, the control unit (10) is configured to,

[0034] In the fourth case (step 940: No), where the prerequisite condition is met, the first direction condition is not met, and the adjacent lane arrow information is not stored in the storage device, it is determined that neither the first execution condition nor the second execution condition is met.

[0035] In the fourth scenario, the storage device contains lane arrow information, but the possible directions of travel for the lanes included in this information do not include the direction corresponding to a steering operation. Therefore, the likelihood of the vehicle intending to turn left or right, at least within the driving lane, is extremely low. Consequently, in the fourth scenario, neither deceleration assist control nor mild deceleration assist control is executed, thereby suppressing unnecessary operation of these controls.

[0036] In one aspect of the invention, the steering information acquisition device is a steering indicator switch (15) capable of detecting the operating state of an operator (WL) operated by the driver in order to make the steering indicator (18) work, and configured to acquire whether the operator (WL) is in a state operated by the driver as the steering information.

[0037] Based on this configuration, since the operating state of the operator can be properly detected, highly reliable steering information can be obtained.

[0038] Vehicles based on the present invention are equipped with the device of the present invention.

[0039] The driving assistance method based on the present invention includes the following steps:

[0040] The surrounding information acquisition device (11, 12) acquires road markings and information related to the intersection existing in the area ahead as surrounding information, wherein the area ahead is the area including the road surface in front of the vehicle.

[0041] The steering information acquisition device (15) acquires information including whether the driver of the vehicle has made a steering operation as steering information;

[0042] When an intersection is detected based on the surrounding information (step 905: Yes), and a road arrow mark is detected on the lane in which the vehicle is traveling (i.e., the driving lane) or on the adjacent lane (i.e., the adjacent lane), for each lane, the road arrow information, which includes the road arrow mark and the driving direction of the lane indicated by it, is associated with the detected intersection and stored in the storage device (step 1020).

[0043] If the first execution condition, including the detection of an intersection based on the surrounding information, is met, a driver assistance control is executed, including at least one of left / right turn pre-turn deceleration assist control and left / right turn pre-turn warning control. The left / right turn pre-turn deceleration assist control automatically applies braking force to the vehicle in a manner that makes the vehicle's deceleration consistent with a target deceleration, thereby assisting the vehicle in decelerating to a predetermined target speed before making a right or left turn at the detected intersection. The left / right turn pre-turn warning control alerts the driver, thereby prompting the driver to decelerate before making a right or left turn at the detected intersection.

[0044] If the prerequisite condition is met (step 915: yes) when an intersection is detected based on the surrounding information and the driver is determined to be performing a steering operation based on the steering information, it is determined whether the first execution condition is met (step 925, step 950) based on the steering operation being performed and the driving lane arrow information stored in the storage device as the driving lane or the adjacent lane arrow information as the adjacent lane.

[0045] According to this driving assistance method, driving assistance control can be performed appropriately.

[0046] The computer-readable, non-transient recording medium based on the present invention records a driving assistance program, which enables a computer to perform the following steps:

[0047] The step of enabling the surrounding information acquisition device (11, 12) to acquire road markings and information related to the intersection existing in the area ahead as surrounding information, wherein the area ahead is the area including the road surface in front of the vehicle;

[0048] The step of enabling the steering information acquisition device (15) to acquire information including whether the driver of the vehicle has made a steering operation as steering information;

[0049] When an intersection is detected based on the surrounding information (step 905: Yes), and a road arrow mark is detected on the lane in which the vehicle is traveling (i.e., the driving lane) or the lane adjacent to the driving lane (i.e., the adjacent lane) (step 1010: Yes), for each lane, the information including the road arrow mark and the travel direction of the lane indicated by it, i.e., the road arrow information, is associated with the detected intersection and stored in the storage device (step 1020).

[0050] If the first execution condition, including the detection of an intersection based on the surrounding information, is met, a step of driver assistance control is executed, including at least one of left / right turn pre-turn deceleration assist control and left / right turn pre-turn warning control. The left / right turn pre-turn deceleration assist control automatically applies braking force to the vehicle in a manner that makes the vehicle's deceleration consistent with a target deceleration, thereby assisting the vehicle in decelerating to a predetermined target speed before making a right or left turn at the detected intersection. The left / right turn pre-turn warning control alerts the driver, thereby prompting the driver to decelerate before making a right or left turn at the detected intersection.

[0051] If the premise that an intersection is detected based on the surrounding information and the driver is determined to be performing a steering operation based on the steering information is met (step 915: Yes), the first execution condition is determined (steps 925 and 950) based on the steering operation being performed and the driving lane arrow information stored in the storage device as the driving lane or the adjacent lane arrow information as the adjacent lane.

[0052] By having a computer execute a driving assistance program recorded on the recording medium, driving assistance controls can be performed appropriately.

[0053] In the above description, in order to help understand the invention, the constituent elements of the invention corresponding to the embodiments are added in parentheses by reference numerals used in the embodiments, but the constituent elements of the invention are not limited to the embodiments specified by the reference numerals. Attached Figure Description

[0054] Figure 1 This is a schematic configuration diagram of a driving assistance device (this embodiment) according to an embodiment of the present invention.

[0055] Figure 2 This is a diagram illustrating the different types of arrow markings on the road surface.

[0056] Figure 3 It is a graph showing the time-varying deceleration of the vehicle when performing left and right turn pre-turn deceleration assist control and left and right turn pre-turn slight deceleration assist control.

[0057] Figure 4 This is another graph showing the time-varying deceleration of the vehicle when both left and right turn deceleration assist control and left and right turn light deceleration assist control are implemented.

[0058] Figure 5 This diagram illustrates a situation where the first execution condition is met based on the information from the driving lane arrow.

[0059] Figure 6A For comparison, a diagram illustrates a situation where the first execution condition is deemed invalid based on the lane arrow information.

[0060] Figure 6B For comparison, a diagram illustrates another situation where the first execution condition is deemed invalid based on the lane arrow information.

[0061] Figure 7A This diagram illustrates a situation where the first execution condition is met based on the information from the arrows in the adjacent lanes.

[0062] Figure 7B This diagram illustrates another situation where the first execution condition is met based on the information from the arrows in the adjacent lanes.

[0063] Figure 8A This diagram illustrates a situation where the second execution condition is determined to be met based on the information from the arrows in the adjacent lanes.

[0064] Figure 8B This diagram illustrates another situation where the second execution condition is determined to be met based on the information from the arrows in the adjacent lanes.

[0065] Figure 9 This is a flowchart illustrating the routine executed by the CPU of the left and right turn deceleration assist ECU of the second implementation device.

[0066] Figure 10 This is a flowchart illustrating the routines executed by the CPU.

[0067] Figure 11 This is a flowchart illustrating the routines executed by the CPU. Detailed Implementation

[0068] (Implementation Method)

[0069] (constitute)

[0070] Hereinafter, a driving assistance device (hereinafter also referred to as "this embodiment device") according to an embodiment of the present invention will be described with reference to the accompanying drawings. Figure 1 As shown, this embodiment includes a left and right turn deceleration assist ECU 10 and connected to it a camera sensor 11, a radar sensor 12, a vehicle speed sensor 13, an acceleration sensor 14, a turn signal switch 15, a drive unit 16, a braking unit 17, and a turn signal 18. The left and right turn deceleration assist ECU 10 has a microcomputer as its main component. ECU is an abbreviation for Electronic Control Unit. The microcomputer includes a CPU, ROM, RAM, and interfaces (I / F), etc. The CPU implements various functions by executing instructions (programs, routines) stored in the ROM. In addition, some functions can also be implemented by other ECUs. Hereinafter, the vehicle equipped with this embodiment (in other words, the vehicle equipped with this embodiment) will be referred to as the "own vehicle".

[0071] The left and right turn deceleration assist ECU 10 is configured to acquire, generate, or detect information or signals output by, or detected by the aforementioned sensors and switches 11 to 15 at predetermined intervals, and control elements 16 to 18 based on the acquired signals. Hereinafter, the left and right turn deceleration assist ECU 10 will also be referred to as "ECU 10".

[0072] Camera sensor 11 is mounted on the back of the vehicle's interior mirror (interior mirror / rearview mirror). Camera sensor 11 captures images of the landscape in front of the vehicle, including the road surface, and identifies (detects) road markings present in the area ahead. Road markings include lane markings extending in front of the vehicle and road arrow markings on the driving lane and adjacent lanes. The driving lane is the lane in which the vehicle travels. Adjacent lanes are lanes adjacent to the driving lane, including right-hand adjacent lanes to the right of the driving lane and left-hand adjacent lanes to the left of the driving lane. A lane is defined as the area between two adjacent lane markings. Road arrow markings are arrow-shaped road markings indicating the direction of travel for a lane. Typically, multiple road arrow markings are spaced apart along the direction of lane extension before intersections. Road arrow markings include "traffic division by direction of travel" and "direction of travel." "Traffic division by direction of travel" is typically placed on each lane of a road with two or more lanes on one side. On the other hand, the "direction of travel" is set at locations where it is necessary to indicate the direction in which vehicles can travel, so it is unrelated to the type of lanes set.

[0073] Figure 2 This is a diagram showing the main types of road arrow markings. For example... Figure 2As shown, in road arrow mark E1, the arrow indicates a left direction, so the lane marked with arrow E1 is designated for left turns (i.e., this lane is a dedicated left-turn lane). In road arrow mark E2, the arrow indicates both forward and left directions, so the lane marked with arrow E2 is designated for both straight-ahead and left-turn directions. In road arrow mark E3, the arrow indicates forward, so the lane marked with arrow E3 is designated for straight-ahead directions. In road arrow mark E4, the arrow indicates both forward and right directions, so the lane marked with arrow E4 is designated for both straight-ahead and right-turn directions. In road arrow mark E5, the arrow indicates right direction, so the lane marked with arrow E5 is designated for right turns (i.e., this lane is a dedicated right-turn lane).

[0074] return Figure 1 Continuing with the explanation, camera sensor 11 includes an image recognition ECU (not shown) that uses machine learning to recognize road arrow markings. Specifically, the image recognition ECU pre-learns learning data containing all possible road arrow markings that may be marked on the road surface. The road arrow markings included in the learning data include, for example, arrow markings of different sizes and / or shapes depending on the region, and arrow markings of varying degrees of blur. Each road arrow marking is associated with and stored in the learning data with the traversable direction indicated by that arrow marking. Using the learning results from the learning data, the image recognition ECU identifies the road arrow markings from the image data and calculates their traversable direction.

[0075] In addition, based on image data, camera sensor 11 also identifies (detects) traffic lights in the area in front of its own vehicle, besides road markings, and calculates the relative relationship between its own vehicle and the traffic lights. Here, "relative relationship between its own vehicle and the traffic lights" includes the distance from its own vehicle to the traffic lights and the position of the traffic lights relative to its own vehicle.

[0076] In addition, the camera sensor 11 can also be configured to identify moving objects such as other vehicles and pedestrians, as well as stationary objects such as the central divider and guardrails, in addition to traffic lights. The "relative relationship between the vehicle and the traffic lights" calculated by the camera sensor 11 is equivalent to an example of "information related to the intersection".

[0077] The camera sensor 11 acquires this information as "camera surrounding information" and outputs it to the ECU 10. The camera sensor 11 is an example of a "surrounding information acquisition device." Alternatively, the ECU 10 can also acquire information about road markings and intersections in the area in front of the vehicle from a navigation system (not shown). In this case, the navigation system is an example of a "surrounding information acquisition device."

[0078] The radar sensor 12 is located in the center of the front grille of the vehicle. The radar sensor 12 projects millimeter-wave radio waves towards the area in front of the vehicle and receives reflected waves from any three-dimensional objects present. Based on the timing of the radio wave projection and reception, the radar sensor 12 calculates the presence or absence of the three-dimensional object and the relative relationship between the vehicle and the object. The radar sensor 12 obtains this information as "radar ambient information" and outputs it to the ECU 10. The radar sensor 12 is an example of an "ambient information acquisition device."

[0079] Furthermore, the location of the radar sensor 12 is not limited to the center of the front grille; for example, it may be located in the center of the front bumper of the vehicle or at least one of the left or right corners of the front bumper.

[0080] The ECU 10 detects road surface arrow markings on the driving lane based on camera surrounding information and determines the permissible direction of travel for the driving lane indicated by the arrow markings. Additionally, the ECU 10 detects traffic lights based on both camera surrounding information and radar surrounding information to detect intersections. By detecting traffic lights based on both camera surrounding information and radar surrounding information, the accuracy of calculating the relative relationship between the vehicle and the traffic lights is improved. In other words, the accuracy of intersection detection is improved. Camera surrounding information and radar surrounding information are examples of "surrounding information." However, this embodiment may also lack a radar sensor 12. In this case, camera surrounding information alone is an example of "surrounding information."

[0081] The vehicle speed sensor 13 generates a signal corresponding to the vehicle's speed (hereinafter referred to as "vehicle speed"). The ECU 10 acquires the signal generated by the vehicle speed sensor 13 and calculates the vehicle speed based on the signal.

[0082] Accelerometer sensor 14 generates signals corresponding to the vehicle's acceleration and deceleration. ECU 10 receives these signals and calculates the acceleration and deceleration based on them. Deceleration has negative values. The smaller the deceleration, the greater the degree of deceleration.

[0083] The turn signal switch 15 is located on the turn signal stalk WL (not shown). The turn signal stalk WL is a driver-operated device located on the steering column to activate (flash) the turn signal. The turn signal stalk WL is activated by the driver when making a left or right turn or changing lanes.

[0084] Specifically, the turn signal stalk WL is configured to move from a neutral position to a right position PR or a left position PL, centered on a pivot axis. The right position PR or left position PL represents a position rotated by a predetermined angle, either counterclockwise or counterclockwise. The turn signal switch 15 includes a right switch 15R and a left switch 15L. The right switch 15R is activated (generating an activation signal) when the turn signal stalk WL is in the right position PR, and deactivated (generating a deactivation signal) otherwise. The left switch 15L is activated (generating an activation signal) when the turn signal stalk WL is in the left position PL, and deactivated (generating a deactivation signal) otherwise. That is, the turn signal switch 15 obtains whether the turn signal stalk WL is in an activated state (i.e., in the right position PR or left position PL) as turn information. The ECU 10 detects the operating state of the turn signal stalk WL based on the turn information (i.e., based on the signal obtained from the turn signal switch 15). The turn signal stalk WL is equivalent to an example of an "operator". The turn signal switch 15 is an example of a "turn information acquisition device" or "direction indicator switch".

[0085] The drive unit 16 is a device for applying driving force to its drive wheels to propel the vehicle. The braking unit 17 is a device for applying braking force to its wheels to brake the vehicle.

[0086] The ECU 10 controls the driving force and / or braking force by controlling the operation of the drive unit 16 and / or the braking unit 17, thereby enabling the drive unit 16 and / or the braking unit 17 to perform left and right turn pre-turn deceleration assist control or left and right turn pre-turn slight deceleration assist control. Both left and right turn pre-turn deceleration assist control and left and right turn pre-turn slight deceleration assist control are types of driver assistance control.

[0087] The deceleration assist control before left and right turns automatically applies braking force to the vehicle in a manner that matches the vehicle's deceleration to a target deceleration (described later). This assists in decelerating the vehicle before making a right or left turn at an intersection. The target deceleration is the deceleration required to reduce the vehicle speed to a predetermined target speed, and can be calculated by ECU 10. The target speed is the upper limit of the vehicle's speed at which it can appropriately (safely) make a right or left turn at an intersection, and can be preset through experimentation or simulation.

[0088] Light deceleration assist control before left and right turns is a control that reduces the degree of vehicle deceleration to the target speed compared to the previous control.

[0089] Hereinafter, the deceleration assist control before left and right turns will also be referred to as "deceleration assist control", and the light deceleration assist control before left and right turns will also be referred to as "light deceleration assist control".

[0090] Figure 3This is a graph showing the time-varying deceleration G of the vehicle when performing deceleration assist control and mild deceleration assist control. In deceleration assist control, a lower limit value Gth1 (<0) of the target deceleration is set, and in mild deceleration assist control, a lower limit value Gth2 (<0) of the target deceleration is set. The lower limit value Gth2 is greater than the lower limit value Gth1.

[0091] like Figure 3 As shown, in this embodiment, under any control condition, after calculating the target deceleration, the vehicle's deceleration G is reduced with a constant jerk until the target deceleration is reached, and its value is maintained at deceleration G at the moment the target deceleration is reached. Furthermore, the jerk is the rate of change of deceleration over time, equal to the slope of the solid line 20. However, when the target deceleration is less than the lower limit Gth (Gth = Gth1 in deceleration assist control, and Gth = Gth2 in mild deceleration assist control), the deceleration G stops decreasing at the moment the lower limit Gth is reached, and the deceleration G is maintained at the lower limit Gth. According to this configuration, when mild deceleration assist control is implemented, when the target deceleration is above the lower limit Gth2, the degree of deceleration is no different from that of deceleration assist control; however, when the target deceleration is less than the lower limit Gth2, the degree of deceleration is reduced compared to deceleration assist control.

[0092] Furthermore, the time shift of the vehicle's deceleration G when performing deceleration assist control and mild deceleration assist control is not limited to... Figure 3 As shown. For example, it can also be done as follows: Figure 4 As shown, the lower limit of the target deceleration for both deceleration assist control and mild deceleration assist control is set to the same value, Gth1. Furthermore, the acceleration during mild deceleration assist control (the slope of the solid line 22) can be greater than the acceleration during deceleration assist control (the slope of the solid line 21) (in other words, the deceleration can be smoother). With this configuration, the deceleration degree is reduced compared to deceleration assist control.

[0093] The turn signals 18 include a right turn signal 18R and a left turn signal 18L. The right turn signal 18R is located at the front right corner and rear right corner of the vehicle. The left turn signal 18L is located at the front left corner and rear left corner of the vehicle. The ECU 10 causes the corresponding turn signal 18 (18R, 18L) to flash while the turn signal stalk WL is in the right position PR or the left position PL (i.e., while the right switch 15R or the left switch 15L generates an on signal). Furthermore, the turn signals 18 can also be controlled by other ECUs (e.g., the instrument cluster ECU). The turn signals 18 are an example of a "direction indicator".

[0094] (Job details)

[0095] Next, the details of the operation of ECU 10 will be explained. ECU 10 performs deceleration assist control when the first execution condition is met, and performs mild deceleration assist control when the second execution condition is met. The first execution condition is met when all of the following conditions 1 to 4 are met.

[0096] (Condition 1) An intersection was detected.

[0097] (Condition 2) The turn signal switch 15 is in the ON state.

[0098] (Condition 3) The road surface arrow information of the driving lane is stored in the RAM of ECU 10 (described later).

[0099] (Condition 4) The direction of travel of the driving lane included in the road surface arrow information of the driving lane includes the direction of turn signal switch 15 being turned on.

[0100] When the ECU 10 detects a traffic light based on information from the camera's surroundings and radar's surroundings, it determines that condition 1 is met. Alternatively, the camera sensor 11 can be configured to calculate the relative relationship between its own vehicle and warning signs at road intersections by recognizing these signs. The ECU 10 can also detect intersections by detecting warning signs based on camera surroundings information (and radar surroundings information) that includes this relative relationship.

[0101] If condition 1 is met, and the signal obtained from the turn signal switch 15 includes the activation signal of the right switch 15R or the left switch 15L, then ECU 10 determines that condition 2 is met. Conditions 1 and 2 are equivalent to an example of "prerequisite conditions".

[0102] Alternatively, condition 2 can be configured to occur when the detected value from the steering angle sensor and / or steering torque sensor is above a predetermined threshold. The steering angle sensor and / or steering torque sensor are sensors that detect input values ​​based on the driver's steering input.

[0103] When ECU 10 determines the permissible direction of travel indicated by the road surface arrow markings of each lane detected based on camera surrounding information, under condition 1, it associates and stores the "information including the road surface arrow markings and the corresponding permissible direction of travel of the lanes indicated therein," i.e., the road surface arrow information, with each lane and intersection (the intersection detected based on the fulfillment of condition 1) in RAM. ECU 10 is configured to store road surface arrow information related to the road surface arrow markings of the driving lane and adjacent lanes. Hereinafter, the road surface arrow information related to the road surface arrow markings of the driving lane is referred to as "driving lane arrow information," the road surface arrow information related to the road surface arrow markings of the right adjacent lane is referred to as "right adjacent lane arrow information," and the road surface arrow information related to the road surface arrow markings of the left adjacent lane is referred to as "left adjacent lane arrow information." Furthermore, when it is not necessary to distinguish between right adjacent lane arrow information and left adjacent lane arrow information, it is simply referred to as "adjacent lane arrow information." Further, when it is not necessary to distinguish between driving lane arrow information and adjacent lane arrow information, it is simply referred to as "road surface arrow information."

[0104] ECU 10 is configured to, when a road arrow mark is detected, overwrite the road arrow information stored in RAM with the road arrow information associated with the detected road arrow mark for each lane, and retain the road arrow information stored in RAM when no road arrow mark is detected.

[0105] If lane arrow information is stored in RAM when conditions 1 and 2 are met, ECU 10 determines that condition 3 is met. "Conditions 1 to 3 being met" is equivalent to an example of "Case 1".

[0106] In addition, ECU 10 is configured to erase the road arrow information from RAM at the point in time when the state changes from detecting any intersection (detected state) to not detecting (undetected state) (typically, the point in time when the intersection has passed).

[0107] When conditions 1 to 3 are met (first condition), ECU 10 determines that condition 4 is met if the direction of the turn signal switch 15 (hereinafter also referred to as the "turn signal on direction") is included in the permissible direction of travel of the driving lane contained in the driving lane arrow information. For example, condition 4 is met when the permissible direction of travel contained in the driving lane arrow information is "straight direction and left turn direction" and the left switch 15L is in the on state. Condition 4 is equivalent to an example of the "first direction condition". In addition, the turn signal on direction is equivalent to an example of "the direction corresponding to the currently performed steering operation".

[0108] Reference Figure 5Please provide a detailed explanation. Figure 5 This is a diagram showing the time-varying behavior of a vehicle V with the intention to make a right turn at an intersection (not shown) located in the area ahead. Figure 3 In the example, ECU 10 first detects a traffic light (illustration omitted) in the area ahead at position P1, thus first detecting an intersection. Therefore, condition 1 is met at position P1. Furthermore, for other examples described later ( Figures 6A to 8B It is also assumed that condition 1 holds at position P1.

[0109] Next, the driver of vehicle V operates the turn signal stalk WL clockwise at position P2, moving it to the right position PR. This causes the right switch 15R to change from an off state to an on state at position P2, so ECU 10 begins flashing the right turn signal 18R. As a result, condition 2 is met. Furthermore, for other examples described later ( Figures 6A to 8B It is also assumed that condition 2 holds at position P2.

[0110] Here, when ECU 10 detects an intersection, it detects the road arrow mark A1 in lane L1, the road arrow mark A2 in the adjacent lane L2 to the right, and the road arrow mark A3 in the adjacent lane L3 to the left. Road arrow marks A1 and A2 are... Figure 2 The road arrow marking E5 is of the same type, and the road arrow marking A3 is the same as... Figure 2 The road arrow marking E3 is of the same type. Therefore, ECU 10 associates the "information including road arrow marking A1 and the permissible direction of travel (right turn direction) of the driving lane L1 indicated by it," i.e., the driving lane arrow information, with the intersection and stores it in RAM. In addition, ECU 10 associates the "information including road arrow marking A2 and the permissible direction of travel (right turn direction) of the adjacent right lane L2 indicated by it," i.e., the right adjacent lane arrow information, and the "information including road arrow marking A3 and the permissible direction of travel (straight direction) of the adjacent left lane L3 indicated by it," i.e., the left adjacent lane arrow information, with the intersection and stores them in RAM respectively. Whenever a road arrow marking is detected based on the information around the camera, ECU 10 overwrites the road arrow information stored in RAM with the latest road arrow information for each lane. According to this configuration, at position P1, the driving lane arrow information and the right and left adjacent lane arrow information begin to be stored in RAM, and at position P2, this road arrow information is overwritten, so condition 3 is met.

[0111] At position P2, the travel direction (right turn direction) of lane L1, which is included in the lane arrow information, includes the direction where the turn signal is on (right direction). Therefore, condition 4 is met.

[0112] As a result, the first execution condition was met, so ECU 10 started deceleration assist control at position P2. According to... Figure 5 For example, by assisting in slowing down one's own vehicle V before making a right turn at an intersection, the vehicle speed can be reduced to the target speed, allowing the vehicle V to make a right turn appropriately (safely).

[0113] Here, refer to Figure 6A and Figure 6B A driving assistance device will be described as a comparative example. This driving assistance device is configured to detect only the road surface arrow markings of the driving lane based on information around the camera, thereby associating only the driving lane arrow information with the intersection and storing it in RAM. Furthermore, this driving assistance device is configured to determine that the first execution condition is met and execute deceleration assist control when all of the above conditions 1 to 4 are met.

[0114] Figure 6A and Figure 6B All diagrams illustrate the temporal changes in the actions of the vehicle Vc (a vehicle equipped with the comparative example's driver assistance device). The vehicle Vc has the intent to turn right at an intersection (not shown) located in the area ahead after changing lanes to the adjacent lane on the right. Figure 6A and Figure 6B In the examples, condition 1 is true at position P1 and condition 2 is true at position P2.

[0115] exist Figure 6A In the example, other vehicle Vo is positioned on the foremost road arrow mark A1 among multiple road arrow marks on lane L1. Therefore, arrow mark A1 is obscured by the body of other vehicle Vo and becomes unrecognizable. If other vehicle Vo remains stationary at position P2 between the initial detection of the intersection and the arrival of vehicle Vc, the driver assistance device cannot detect road arrow mark A1 in lane L1 and therefore does not store the lane arrow information in RAM. Thus, in Figure 6A In the example, even if conditions 1 and 2 are met at position P2, condition 3 is not met, so the first execution condition is not met and deceleration auxiliary control is not executed.

[0116] On the other hand, Figure 6B In the example, the driver assistance device detects the road arrow mark A4 on the driving lane L1 during the period from the time the intersection is first detected to the time when its own vehicle Vc arrives at position P2. It associates the driving lane arrow information associated with the arrow mark A4 with the intersection and stores it (overwrites it). Therefore, condition 3 is met.

[0117] However, at location P2, the direction of travel (straight ahead) for lane L1, as indicated by the lane arrow information, does not include the direction where the turn signal is on. Therefore, in Figure 6B In the example, even if conditions 1 to 3 are met at position P2, condition 4 is not met, so the first execution condition is not met and deceleration auxiliary control is not executed.

[0118] exist Figure 6A and Figure 6B In the example, after vehicle Vc changes lanes from lane L1 to the adjacent lane L2 at position P3, lane L2 becomes the new driving lane. Therefore, the driver assistance device detects the road arrow mark A2 of lane L2 at the time when vehicle Vc arrives at position P3 due to the lane change, associates the driving lane arrow information associated with the arrow mark A2 with the intersection and stores it in RAM, and overwrites the driving lane arrow information during subsequent intersection detections. Thus, condition 3 is met at position P3.

[0119] Additionally, at location P3, the permitted travel direction (right turn direction) of lane L2, as indicated by the lane arrow information, includes the direction in which the turn signal is on. Therefore, condition 4 is met.

[0120] As a result, the first execution condition is met, so the driving assistance device performs deceleration assistance control at position P3.

[0121] Based on this configuration, since the deceleration assist control is only executed when the vehicle's Vc reaches position P3, it is consistent with... Figure 5 Compared to the previous example, the timing of implementing deceleration assist control is delayed. As a result, it may not be possible to decelerate to the target speed, or occupants may feel disoriented due to sudden deceleration.

[0122] In this embodiment, the ECU 10 is configured to detect not only the road arrow markings of the driving lane but also the road arrow markings of adjacent lanes based on information surrounding the camera. Therefore, in addition to the driving lane arrow information, the adjacent lane arrow information is also stored in RAM. Furthermore, it is configured to determine whether the first execution condition is met based on the adjacent lane arrow information if the first execution condition is determined not to be met based on the driving lane arrow information.

[0123] Specifically, the first execution condition also applies if all of the following conditions 5 to 7 are met, in addition to conditions 1 and 2 (prerequisites) mentioned above.

[0124] (Condition 5) Condition 3 or Condition 4 is not valid.

[0125] (Condition 6) Adjacent lane arrow information is stored in the RAM of ECU 10.

[0126] (Condition 7) The direction of travel of the adjacent lanes included in the adjacent lane arrow information includes the direction of turn signal switch 15 being turned on, and the direction of travel does not include the straight direction.

[0127] If, under conditions 1 and 2, ECU 10 does not detect the road surface arrow markings of the driving lane during the period from the time the intersection was first detected to the current time, and therefore does not store the driving lane arrow information in RAM, then it determines that condition 5 is met because condition 3 is not met. Furthermore, the situation where condition 5 is met because condition 3 is not met includes, but is not limited to, the following situations. Figure 6A In addition to the examples shown, there are also cases where the road arrow markings on the driving lane are rubbed to a degree that the camera sensor 11 cannot recognize.

[0128] Additionally, if conditions 1 to 3 are met, and the direction of travel included in the lane information does not include the direction where the turn signal is on, ECU 10 determines that condition 5 is met because condition 4 is not met. For example, condition 4 is not met if the direction of travel included in the lane information is "straight ahead" and the right switch 15R is on.

[0129] If conditions 1, 2, and 5 are met, and the RAM contains adjacent lane arrow information corresponding to the turn signal direction, then ECU 10 determines that condition 6 is met. "Conditions 1, 2, 5, and 6 being met" is equivalent to an example of "Case 2". Furthermore, "adjacent lane arrow information corresponding to the turn signal direction" means, for example, when the turn signal direction is right, that the adjacent lane arrow information at least includes the arrow information of the right-hand adjacent lane.

[0130] If conditions 1, 2, 5, and 6 are met (the second condition), and the permitted direction of travel for the adjacent lane (as indicated by the arrow information) is consistent with the direction the turn signal is on, then ECU 10 determines that condition 7 is met. Here, "the permitted direction of travel for the adjacent lane is consistent with the direction the turn signal is on" means that the permitted direction of travel for the adjacent lane is either a right turn or a left turn (i.e., excluding the straight-ahead direction), and is the same as the direction the turn signal is on. In other words, condition 7 can be met if the adjacent lane is a dedicated right-turn lane or a dedicated left-turn lane. Condition 7 is equivalent to an example of the "second direction condition."

[0131] Reference Figure 7A and Figure 7B Please provide a detailed explanation. Figure 7A and Figure 7BThese are all diagrams illustrating the temporal changes of the actions of vehicle V. Vehicle V intends to turn right at an intersection (not shown) in the area ahead after changing lanes to the adjacent lane on the right. Figure 7A It shows the relationship with Figure 6A The same situation, Figure 7B It shows the relationship with Figure 6B The same situation. Therefore, in Figure 7A and Figure 7B In the examples, condition 1 is true at position P1 and condition 2 is true at position P2.

[0132] exist Figure 7A In the example, even if conditions 1 and 2 are true at position P2, condition 3 is not true, so condition 5 is true.

[0133] On the other hand, Figure 7B In the example, even if conditions 1 to 3 are true at position P2, condition 4 is not true, so condition 5 is true.

[0134] exist Figure 7A and Figure 7B In the example, ECU 10 detects the road arrow mark A2 on the adjacent lane L2 during the period from the time it first detects the intersection to the time its own vehicle V arrives at position P2. It then associates and stores (overwrites) the adjacent lane arrow information associated with this arrow mark A2 with the intersection. Therefore, condition 6 is met. Furthermore, since the adjacent lane L2 is a dedicated right-turn lane, at position P2, the permissible direction (right-turn direction) of the adjacent lane L2 contained in the adjacent lane arrow information is consistent with the turn signal on direction. Therefore, condition 7 is met.

[0135] As a result, the first execution condition is met, so ECU 10 performs deceleration assist control at position P2. According to this configuration, even if conditions 1 and 2 are met but conditions 3 or 4 are not met, thus determining that the first execution condition is not met, the first execution condition will still be determined to be met when conditions 5 to 7 are met. In other words, even if the first execution condition is determined to be not met based on the driving lane arrow information, the determination of whether the first execution condition is met will be based on the adjacent lane arrow information. Therefore, compared with... Figure 5 Compared to the previous example, it can execute deceleration assist control at the same time. As a result, it can appropriately decelerate to the target speed, making it less likely that passengers will feel uneasy due to sudden deceleration. Therefore, it can execute deceleration assist control at the appropriate time.

[0136] Additionally, if conditions 1, 2, 5, and 6 are met, and condition 7 is not met because "the drivable direction of the adjacent lane contained in the adjacent lane arrow information includes the direction of turn signal activation, and the drivable direction includes the straight direction", then ECU 10 determines that the first execution condition is not met but the second execution condition is met, and executes mild deceleration assist control.

[0137] Reference Figure 8A and Figure 8B Please provide a detailed explanation. Figure 8A and Figure 8B These are all graphs showing the historical changes in the actions of their own vehicle V. Figure 8A It shows the relationship with Figure 7A The same situation, Figure 8B It shows the relationship with Figure 7B The same situation. However, in Figure 8A and Figure 8B In the middle, a road arrow mark A5 is set on the right adjacent lane (and...). Figure 2 The road arrow marking E4 (of the same type) is used to replace the road arrow marking A2. Therefore, in Figure 8A and Figure 8B In the examples, condition 1 is true at position P1, and conditions 2, 5, and 6 are true at position P2. Additionally, in... Figure 8A In the example, condition 5 is true because condition 3 is false. Figure 8B In the example, condition 5 is true because condition 4 is false.

[0138] exist Figure 8A and Figure 8B In the examples, condition 7 is not met because "the travel directions (straight and right turns) of the right adjacent lane included in the right adjacent lane arrow information contain the turn signal on direction, and the travel direction includes the straight direction".

[0139] As a result, the second execution condition is met, so ECU 10 performs mild deceleration assist control at position P2. For example... Figure 8A and Figure 8BAs illustrated in the example, when the permissible direction of travel indicated by the road arrow markings of adjacent lanes (strictly speaking, the adjacent lane on the side where the turn signal is on) includes both the turn signal on direction and the straight-ahead direction, it is difficult to determine whether the vehicle V intends to turn left or right at the intersection after changing lanes, or simply intends to change lanes into the adjacent lane. Therefore, by implementing mild deceleration assist control instead of full deceleration assist control in such situations, it is possible to decelerate the vehicle V to a certain extent before making a lane change if the vehicle V intends to turn left or right at the intersection after changing lanes, and on the other hand, to reduce the degree of unnecessary deceleration felt by the driver if the vehicle V only intends to change lanes into the adjacent lane.

[0140] On the other hand, if conditions 1, 2, 5 and 6 are met, and condition 7 is not met because "the direction of travel of the adjacent lane contained in the adjacent lane arrow information does not include the direction of turn signal on", then ECU 10 determines that both the first and second execution conditions are not met, and does not execute deceleration assist control and mild deceleration assist control.

[0141] The situation described as "where the permitted direction of travel in the adjacent lane does not include the direction in which the turn signal is on" includes, for example, situations where the permitted direction of travel in the adjacent lane is straight and the turn signal is on in the right or left direction. In such cases, there is a high probability that vehicle V will activate the turn signal stalk WL solely to change lanes to the adjacent lane. In other words, there is a high probability that vehicle V does not intend to turn left or right at the intersection. Therefore, in such situations, neither deceleration assist control nor mild deceleration assist control is activated, thereby preventing these controls from performing unnecessary operations.

[0142] Furthermore, if condition 6 is not met when conditions 1, 2, and 5 are met, ECU 10 determines that the first execution condition is not met and does not execute deceleration assist control. Here, "when condition 6 is not met when conditions 1, 2, and 5 are met" can be categorized into two situations: "condition 5 is met because condition 3 is not met" and "condition 5 is met because condition 4 is not met." In the former case, ECU 10 determines that the first execution condition is not met but the second execution condition is met, thus executing mild deceleration assist control. In the latter case, ECU 10 determines that both the first and second execution conditions are not met, thus not executing deceleration assist control or mild deceleration assist control.

[0143] In the former case, the lane arrow information is not stored in RAM. On the other hand, in the latter case, the lane arrow information is stored in RAM, but the possible directions of travel for the lanes included in this information do not include the direction of turn signal activation. That is, in the latter case, at least within the driving lane, the likelihood of vehicle V intending to turn left or right at the intersection is extremely low. However, in the former case, the road surface arrow markings in the driving lanes are only unrecognizable due to the presence of other vehicles or friction, so it is actually possible that the possible directions of travel for the driving lanes include the direction of turn signal activation. In other words, vehicle V may intend to turn left or right at the intersection.

[0144] Therefore, by implementing mild deceleration assist control in the former case, it is possible to decelerate the vehicle V to a certain extent when the vehicle V intends to turn left or right at an intersection in the driving lane, and on the other hand, it is possible to reduce the degree of deceleration that makes the driver feel unnecessary when the vehicle V does not have such an intention (in other words, only has the intention to change lanes).

[0145] In addition, in the latter case, neither deceleration assist control nor mild deceleration assist control is executed, thereby suppressing these controls from generating unnecessary work.

[0146] In addition, "the former case" is equivalent to an example of "the third case", and "the latter case" is equivalent to an example of "the fourth case".

[0147] (Specific tasks)

[0148] Next, the specific operation of ECU 10 will be explained. The CPU of ECU 10 is configured to repeatedly execute in parallel after a predetermined calculation period while the ignition switch is in the ON position. Figure 9 and Figure 10 The flowchart shows the routines and... Figure 11 The routine is shown in the flowchart.

[0149] When the specified timer is reached, the CPU switches from... Figure 9 The process begins at step 900 and proceeds to step 905, where, based on information about the camera's surroundings and radar's surroundings, it is determined whether an intersection (in this embodiment, a traffic light) has been detected (Condition 1 (a constituent element of the prerequisite)).

[0150] If no intersection is detected (step 905: No), the CPU proceeds to step 995 and temporarily terminates the routine.

[0151] On the other hand, if an intersection is detected (step 905: Yes), the CPU proceeds to step 910 to perform road arrow information overlay / maintenance processing. See reference... Figure 10 This process will be explained. After the CPU proceeds to step 910, from... Figure 10 The process begins at step 1000 and proceeds to step 1010, where it is determined whether road arrow markings are detected based on information about the area around the camera.

[0152] If a road arrow mark is detected (step 1010: Yes), the CPU proceeds to step 1020, whereby, for each lane, the road arrow information stored in RAM is overwritten with road arrow information associated with the road arrow mark detected in step 1010. Alternatively, if no road arrow information is stored in RAM, for each lane, the road arrow information associated with the road arrow mark detected in step 1010 is associated with the intersection and stored in RAM (i.e., no overwriting process is performed).

[0153] On the other hand, if no road arrow markings are detected (step 1010: No), the CPU proceeds to step 1030 to retain the road arrow information stored in RAM. Alternatively, if the road arrow information is not stored in RAM, no retention process is performed.

[0154] After completing step 1020 or step 1030, the CPU proceeds to step 1095. Figure 9 Step 915. In step 915, the CPU determines whether the turn signal switch 15 (right switch 15R or left switch 15L) is in the ON state based on the signal obtained from the turn signal switch 15 (condition 2 (a component of the precondition)).

[0155] If the turn signal switch 15 is in the off state (step 915: No), the CPU proceeds to step 995 and temporarily terminates the routine.

[0156] On the other hand, when the turn signal switch 15 is in the on state (step 915: Yes), the CPU proceeds to step 920, performing overlay / hold processing based on the road arrow information (refer to...). Figure 10 Based on the result, determine whether the driving lane arrow information is stored in RAM (condition 3).

[0157] If the driving lane arrow information is stored in RAM (step 920: Yes (first case)), the CPU proceeds to step 925 and determines whether the driving lane direction included in the driving lane arrow information includes the turn signal switch 15 on direction (turn signal on direction) (condition 4 (first direction condition)).

[0158] If the driving lane's travel direction includes the direction where the turn signal is on (step 925: Yes), the CPU determines that the first execution condition is met (i.e., the vehicle intends to turn left or right), and proceeds to step 930 to execute deceleration assist control (refer to...). Figure 5 After this, the CPU proceeds to step 995, temporarily terminating this routine.

[0159] Conversely, if no lane arrow information is stored in RAM (step 920: No), the CPU determines that condition 5 is true and proceeds to step 935. In step 935, the CPU determines whether adjacent lane arrow information is stored in RAM (condition 6).

[0160] If the adjacent lane arrow information is stored in RAM (step 935: Yes (second case)), the CPU proceeds to step 945.

[0161] Additionally, if the driving lane does not include the direction in which the turn signal is on (step 925: No), the CPU determines that condition 5 is true and proceeds to step 940. In step 940, the CPU determines whether adjacent lane arrow information is stored in RAM (condition 6).

[0162] If the adjacent lane arrow information is stored in RAM (step 940: Yes (second case)), the CPU proceeds to step 945.

[0163] After the CPU proceeds to step 945, it determines whether the direction in which the turn signal is on is included in the travelable direction of the adjacent lane contained in the adjacent lane arrow information.

[0164] If the travel direction of the adjacent lane includes the direction in which the turn signal is on (step 945: Yes), the CPU proceeds to step 950 to determine whether the travel direction of the adjacent lane includes the straight direction (condition 7 (second direction condition)).

[0165] If the permissible direction of travel in the adjacent lane does not include the straight-ahead direction (in other words, the permissible direction of travel in the adjacent lane is the same as the direction the turn signal is on) (step 950: No), the CPU determines that the first execution condition is met (i.e., the vehicle intends to turn left or right after changing lanes), and proceeds to step 930 to execute deceleration assist control. After this, the CPU proceeds to step 995, temporarily ending this routine.

[0166] On the other hand, if the travel direction of the adjacent lane includes a straight-ahead direction (step 950: Yes), the CPU determines that the first execution condition is not met but the second execution condition is met (i.e., it is difficult to determine whether the vehicle intends to turn left or right after changing lanes, or only intends to change lanes), and proceeds to step 955 to perform mild deceleration assist control. After this, the CPU proceeds to step 995 and temporarily ends this routine.

[0167] Additionally, if the direction of travel in the adjacent lane does not include the direction in which the turn signal is on (step 945: No), the CPU determines that neither the first nor the second execution condition is met (i.e., the vehicle only intends to change lanes), and proceeds to step 995, temporarily ending the current routine. In this case, neither the deceleration assist control nor the mild deceleration assist control is executed.

[0168] Conversely, if the driving lane arrow information is not stored in RAM (step 920: No) and the adjacent lane arrow information is also not stored (step 935: No (third case)), the CPU determines that the first execution condition is not met but the second execution condition is met (i.e., the vehicle may intend to turn left or right in the driving lane), and proceeds to step 960 to perform mild deceleration assist control. After this, the CPU proceeds to step 995, temporarily ending this routine.

[0169] On the other hand, if the driving lane does not include the direction in which the turn signal is on (step 925: No) and there is no adjacent lane arrow information stored in RAM (step 940: No (fourth case)), the CPU determines that neither the first nor the second execution condition is met (i.e., the vehicle does not intend to turn left or right in the driving lane), and proceeds to step 995, temporarily ending the current routine. In this case, neither the deceleration assist control nor the mild deceleration assist control is executed.

[0170] In parallel, the CPU from Figure 11 The process begins at step 1100 and proceeds to step 1110, where, based on information about the camera's surroundings and radar's surroundings, it is determined whether the state of detecting an intersection (detection state) has changed to the state of not being detected (non-detection state).

[0171] When the state changes from detection to non-detection (step 1110: Yes), the CPU determines that the intersection has been passed and proceeds to step 1120 to erase the road arrow information stored in RAM. After this, the CPU proceeds to step 1195 and temporarily terminates this routine.

[0172] On the other hand, if the detection state is maintained, or if no intersection was detected to begin with (step 1110: No), the CPU proceeds to step 1195 and temporarily terminates the routine.

[0173] As described above, in this embodiment, the determination of whether the first execution condition is met is based not only on the driving lane arrow information but also on the adjacent lane arrow information. Therefore, even if the first execution condition is determined to be unmet based on the driving lane arrow information, the determination of whether the first execution condition is met can still be based on the adjacent lane arrow information. Therefore, compared to a configuration that determines the condition solely based on the driving lane arrow information, it is less likely to experience a delay in determining whether the first execution condition is met, resulting in the ability to execute driver assistance control at the appropriate time.

[0174] The driving assistance device, vehicle, driving assistance method and recording medium involved in the above embodiments have been described, but the present invention is not limited to the above embodiments and various modifications can be made without departing from the purpose of the present invention.

[0175] For example, in the above embodiment, if conditions 1, 2, 5, and 6 are met, and the adjacent lane's travel direction, as contained in the adjacent lane arrow information, includes a turn signal on direction and a straight-ahead direction, thus condition 7 is not met, then the second execution condition is determined to be met, and mild deceleration assist control is executed. However, this configuration is not limited to this. For example, ECU 10 can also be configured such that, in this case, the second execution condition is determined to be not met, and mild deceleration assist control is not executed.

[0176] Additionally, the driver assistance system may also include a deceleration assist switch for left and right turns. This switch allows the driver to select whether they wish to activate the deceleration assist control when the activation conditions are met, and can be operated by the driver. The deceleration assist control can be configured to activate when the activation conditions are met, provided the switch is in the on position.

[0177] Furthermore, the conditions for the execution of deceleration assist control may also include any one of the following: "neither the accelerator pedal nor the brake pedal has been operated," "no accelerator pedal operation has been performed," or "no brake pedal operation has been performed." Alternatively, the conditions for the execution of deceleration assist control may also include the condition "based on the driver's acceleration or deceleration operation not being performed." This condition may, for example, be applicable to driver assistance devices installed in one-pedal vehicles. Here, a one-pedal vehicle refers to a vehicle capable of acceleration and deceleration operations with a single pedal; typically, it refers to a vehicle that accelerates when the pedal is pressed and decelerates when the pedal is released.

[0178] Furthermore, if the first execution condition is met, left and right turn warning control can be implemented as an alternative to or supplement to left and right turn deceleration assist control. Left and right turn warning control is a control that alerts the driver, prompting the driver to decelerate their vehicle before making a right or left turn at an intersection. The alert can be given via voice through a speaker or vibration through a buzzer.

[0179] Alternatively, if the second execution condition is met, a mild warning assist control before left and right turns can be executed as an alternative to, or as a supplement to, the mild deceleration assist control before left and right turns. The mild warning assist control before left and right turns is a control that reduces the level of warning to the driver compared to the standard warning control before left and right turns. Here, "reducing the level of warning" refers, for example, to lowering the speaker volume or reducing the vibration of the buzzer.

[0180] Furthermore, the camera sensor 11 can also be configured to identify pedestrian crossings, either as a replacement for or as a supplement to traffic light recognition based on image data, and calculate the relative relationship between its own vehicle and the pedestrian crossing. The ECU 10 can also detect intersections based on this relative relationship. Alternatively, the camera sensor 11 can also be configured to identify median strips, either as a replacement for or as a supplement to traffic light recognition based on image data, and calculate the relative relationship between its own vehicle and the median strip. The ECU 10 can also detect intersections at points where the median strip is interrupted, based on this relative relationship. Additionally, the ECU 10 can also detect median strips based on information surrounding the camera and radar.

[0181] Furthermore, this device can also be mounted on vehicles used in countries where right-hand traffic is permitted. Additionally, the invention is also applicable to vehicles that operate under autonomous driving control (so-called autonomous vehicles).

[0182] Explanation of reference numerals in the attached figures

[0183] 10: ECU for deceleration assist before left and right turns; 11: Camera sensor; 12: Radar sensor; 13: Vehicle speed sensor; 14: Acceleration sensor; 15: Turn signal switch; 16: Drive unit; 17: Braking unit; 18: Turn signal.

Claims

1. A driving assistance device, comprising: A surrounding information acquisition device is capable of acquiring road markings and information related to intersections existing in the area ahead as surrounding information, wherein the area ahead includes the road surface in front of the vehicle. A steering information acquisition device capable of acquiring information including whether the driver of the vehicle has made steering operations as steering information; and The control unit, having a storage device, is configured to... When an intersection is detected based on the surrounding information, and a road surface arrow mark is detected in the lane in which the vehicle is traveling (i.e., the driving lane) or in a lane adjacent to the driving lane (i.e., the adjacent lane), for each lane, information including the road surface arrow mark and the permissible direction of travel indicated by it (i.e., road surface arrow information) is associated with the detected intersection and stored in the storage device. If the first execution condition, including the detection of an intersection based on the surrounding information, is met, driver assistance control is executed, including at least one of left / right turn pre-turn deceleration assist control and left / right turn pre-turn warning control. The left / right turn pre-turn deceleration assist control automatically applies braking force to the vehicle in a manner that matches the vehicle's deceleration to a target deceleration, thereby assisting the vehicle in decelerating to a predetermined target speed before making a right or left turn at the detected intersection. The left / right turn pre-turn warning control alerts the driver, thereby prompting the driver to decelerate before making a right or left turn at the detected intersection. If the premise that an intersection is detected based on the surrounding information and the driver is determined to be performing a steering operation based on the steering information is met, the first execution condition is determined based on the steering operation being performed and the driving lane arrow information or the adjacent lane arrow information stored in the storage device as the driving lane or the adjacent lane arrow information as the adjacent lane.

2. The driving assistance device according to claim 1, wherein, The control unit is configured to, In the first case, where the aforementioned preconditions are met and the driving lane arrow information is stored in the storage device... When the first directional condition is met, the first execution condition is determined to be met, wherein the first directional condition is met when the direction corresponding to the steering operation being performed is included in the drivable direction of the driving lane as indicated by the driving lane arrow information. In the second case, where the precondition is met, either the driving lane arrow information is not stored in the storage device or the first direction condition is not met, and the adjacent lane arrow information is stored in the storage device... When the second directional condition is met, the first execution condition is determined to be met, wherein the second directional condition is met when the direction corresponding to the steering operation being performed is included in the drivable directions of the adjacent lanes indicated by the adjacent lane arrow information, and the drivable directions do not include a straight-ahead direction. If the second directional condition is not met, it is determined that the first execution condition is not met.

3. The driving assistance device according to claim 2, wherein, The control unit is configured to, Furthermore, if a second specified execution condition is met, including the detection of an intersection based on the surrounding information, the system can execute at least one of two mild driving assistance controls: mild deceleration assist control before left and right turns and mild warning control before left and right turns. Compared to the standard deceleration assist control, the mild deceleration assist control before left and right turns reduces the degree to which the vehicle decelerates to the target speed. Similarly, the mild warning control before left and right turns reduces the degree to which it alerts the driver. In the second case, if the direction corresponding to the steering operation being performed is included in the drivable direction of the adjacent lane indicated by the adjacent lane arrow information and includes a straight direction in that drivable direction, thus the second direction condition is not met, the second execution condition is determined to be met.

4. The driving assistance device according to claim 2 or 3, wherein, The control unit is configured to, Furthermore, if a second specified execution condition is met, including the detection of an intersection based on the surrounding information, the system can execute at least one of two mild driving assistance controls: mild deceleration assist control before left and right turns and mild warning control before left and right turns. Compared to the standard deceleration assist control, the mild deceleration assist control before left and right turns reduces the degree to which the vehicle decelerates to the target speed. Similarly, the mild warning control before left and right turns reduces the degree to which it alerts the driver. In the third case where the preconditions are met and neither the driving lane arrow information nor the adjacent lane arrow information is stored in the storage device, the second execution condition is determined to be met.

5. The driving assistance device according to claim 4, wherein, The control unit is configured to, In the fourth case where the prerequisite condition is met, the first direction condition is not met, and the adjacent lane arrow information is not stored in the storage device, it is determined that neither the first execution condition nor the second execution condition is met.

6. The driving assistance device according to any one of claims 1 to 5, wherein, The steering information acquisition device is a steering indicator switch capable of detecting the operating state of a control device operated by the driver to make the steering indicator work, and is configured to acquire whether the control device is in a state operated by the driver as the steering information.

7. A vehicle having a driving assistance device as described in any one of claims 1 to 6.

8. A driving assistance method, comprising the following steps: The surrounding information acquisition device acquires road markings and information related to intersections existing in the area ahead as surrounding information, wherein the area ahead includes the road surface in front of the vehicle. The steering information acquisition device acquires information including whether the driver of the vehicle has made a steering operation as steering information; When an intersection is detected based on the surrounding information, and a road arrow mark is detected in the lane in which the vehicle is traveling (i.e., the driving lane) or in the adjacent lane (i.e., the adjacent lane), for each lane, information including the road arrow mark and the travel direction of the lane indicated by it (i.e., road arrow information) is associated with the detected intersection and stored in the storage device. If the first execution condition, including the detection of an intersection based on the surrounding information, is met, a driver assistance control is executed, including at least one of left and right turn deceleration assist control and left and right turn warning control. The left and right turn deceleration assist control automatically applies braking force to the vehicle in a manner that makes the vehicle's deceleration consistent with the target deceleration, thereby assisting the vehicle in decelerating to a predetermined target speed before making a right or left turn at the detected intersection. The left and right turn warning control alerts the driver, thereby prompting the driver to decelerate before making a right or left turn at the detected intersection. as well as If the premise that an intersection is detected based on the surrounding information and the driver is determined to be performing a steering operation based on the steering information is met, the first execution condition is determined based on the steering operation being performed and the driving lane arrow information or the adjacent lane arrow information stored in the storage device as the driving lane or the adjacent lane arrow information as the adjacent lane.

9. A computer-readable, non-transitory recording medium containing a driving assistance program, the driving assistance program being used to cause a computer to perform the following steps: The step of enabling the surrounding information acquisition device to acquire road markings and information related to the intersection existing in the area ahead as surrounding information, wherein the area ahead is the area including the road surface in front of the vehicle; The step of enabling the steering information acquisition device to acquire information including whether the driver of the vehicle has made a steering operation as steering information; When a road arrow mark is detected in the lane in which the vehicle is traveling (i.e., the driving lane) or the lane adjacent to the driving lane (i.e., the adjacent lane) when an intersection is detected based on the surrounding information, the step of associating information including the road arrow mark and the travel direction of the lane indicated by it (i.e., road arrow information) with the detected intersection and storing it in a storage device for each lane. If the first execution condition, including the detection of an intersection based on the surrounding information, is met, a step of driver assistance control is executed, including at least one of left / right turn pre-turn deceleration assist control and left / right turn pre-turn warning control. The left / right turn pre-turn deceleration assist control automatically applies braking force to the vehicle in a manner that makes the vehicle's deceleration consistent with a target deceleration, thereby assisting the vehicle in decelerating to a predetermined target speed before making a right or left turn at the detected intersection. The left / right turn pre-turn warning control alerts the driver, thereby prompting the driver to decelerate before making a right or left turn at the detected intersection. If the premise that an intersection is detected based on the surrounding information and the driver is determined to be performing a steering operation based on the steering information is met, the step of determining whether the first execution condition is met is based on the steering operation being performed and the driving lane arrow information or the adjacent lane arrow information stored in the storage device as the driving lane or the adjacent lane arrow information as the road surface arrow information of the adjacent lane.

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