Collision avoidance support system of vehicle, collision avoidance support method, and program of the same

Abstract

To provide a vehicle collision avoidance support making it possible to immediately begin an action of avoiding a collision of an own vehicle with a target in the event that it is estimated that a driver's attention ability to driving may have degraded.SOLUTION: When a first requirement to be established in the event that there is a high possibility that an own vehicle (HV) may collide with a target is established, a driving assist ECU (10) begins a first action (for example, an alarm action) for avoiding the collision of the own vehicle with the target. When a specific condition including at least one of (1) a condition where it is estimated that a user is manipulating an onboard apparatus, (2) a condition where the user uses the onboard apparatus or a portable device connected to the onboard apparatus to speak in a hands-free mode, and (3) a condition where the portable device connected to the onboard apparatus so that the portable device can communicate with the onboard apparatus is receiving an incoming signal has arisen, the driving assist ECU changes the first requirement to a requirement that is established more early than when the specific condition has not arisen.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a vehicle collision avoidance support device, a collision avoidance support method, and a program thereof that perform a collision avoidance support operation for reducing the possibility of a self-vehicle colliding with an object target.

Background Art

[0002] Conventional devices use a driver monitoring camera to capture an image of the driver's face to obtain image data, and when it is detected based on the image data that the driver is in an inattentive state (for example, a side-glancing driving state), an alarm is generated (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

[0004] However, in order to detect that the driver is in an inattentive state using a driver monitoring camera, a certain amount of time is required. Therefore, there is a risk that the timing for executing a collision avoidance support operation including an alarm may be delayed.

[0005] The present invention has been made to solve such problems. That is, one of the objects of the present invention is to provide a vehicle collision avoidance support device, a collision avoidance support method, and a program thereof that can promptly start an operation (first operation) for avoiding a collision between a self-vehicle and an object target when it is estimated that the driver's attention to driving has decreased.

[0006] One aspect of the vehicle collision avoidance support device of the present invention is When a first condition that holds when the host vehicle is likely to collide with an object target is satisfied (S230: Yes), a controller (10) is provided that is configured to start a first operation for avoiding a collision between the host vehicle and the object target (S235). For example, the first condition is a condition that holds when a collision possibility index value (TTC) representing the possibility of collision between the host vehicle and the object target reaches a predetermined threshold value (TTCth). Further, the first operation may be an alarm operation for giving an alarm to the driver, or may be an automatic braking operation.

[0007] Furthermore, the controller When a specific state including at least one of the following states occurs (S330): a state (S320) in which it is presumed that the user of the host vehicle is operating the in-vehicle device mounted on the host vehicle, a state (S340) in which the user is making a call using the in-vehicle device and a portable device communicably connected to the in-vehicle device, and a state (S350) in which the portable device communicably connected to the in-vehicle device is receiving an incoming call signal, the first condition is changed to a first early establishment condition that is a condition that is established earlier than when the specific state does not occur (S390) (S215: Yes, S250).

[0008] When the above specific state occurs, generally, the attention of the driver, who is the user of the host vehicle, to driving decreases. Further, whether or not the above specific state occurs can be immediately detected based on the signal of the in-vehicle device. Therefore, according to the above aspect, when the attention of the driver to driving decreases, the first operation for collision avoidance can be started promptly.

[0009] Note that when the first operation is an operation for generating an alarm (alarm operation), it is desirable that the first condition be changed to the first early establishment condition only when the object target is either a two-wheeled vehicle or a pedestrian. This is because two-wheeled vehicles and pedestrians are object targets that are relatively difficult for a driver with reduced attention to driving to notice. As a result, the driver can recognize a two-wheeled vehicle or a pedestrian that is highly likely to be overlooked by the driver earlier.

[0010] Furthermore, when the apparatus is configured such that the automatic brake is executed at a timing later than the warning operation as the first operation, it is desirable that the automatic brake be executed earlier when a specific state has occurred than when the specific state has not occurred regardless of the type of the target (see S605 to S615 in FIG. 6).

[0011] In the above description, in order to facilitate the understanding of the present invention, the names and / or reference numerals used in the embodiments are appended in parentheses to the configurations of the invention corresponding to the embodiments described later. However, each component of the present invention is not limited to the embodiments defined by the above names and / or reference numerals. The present invention also extends to a vehicle collision avoidance support method and its program. BRIEF DESCRIPTION OF THE DRAWINGS

[0012]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

[0013] A "vehicle collision avoidance support apparatus DS (hereinafter referred to as the 'apparatus DS')" according to an embodiment of the present invention includes the components shown in FIG. 1 and is applied (mounted) to the host vehicle HV. The host vehicle HV may be any of a vehicle having an internal combustion engine as a power source, a vehicle having an electric motor as a power source (i.e., an electric vehicle), and a hybrid vehicle.

[0014] In this specification, "ECU" is an electronic control unit (control unit) including a microcomputer having a CPU (processor), ROM, RAM, a writable non-volatile memory for data, an interface, etc. The ECU is also referred to as a controller or a computer. A plurality of ECUs shown in FIG. 1 are connected to be able to exchange information with each other through CAN (Controller Area Network). Some or all of these plurality of ECUs may be integrated into one ECU.

[0015] The driving support ECU 10 executes collision avoidance support control (driving support control) for reducing the possibility that the host vehicle collides with an object (obstacle) using the components described in FIG. 1.

[0016] The camera device 20 includes a camera 21 and an image ECU 22. The camera 21 captures an image of a scene in front of the host vehicle HV every time a predetermined time elapses to acquire image data. The image ECU 22 generates camera information every time a predetermined time elapses based on the image data and transmits the camera information to the driving support ECU 10. The camera information includes the image data itself and camera target information such as "position, relative longitudinal speed, relative lateral speed, and type of the captured target with respect to the host vehicle HV". The types of targets include other vehicles, two-wheeled vehicles (including motorcycles, bicycles, electric kick scooters, etc.), and pedestrians.

[0017] The radar device 30 is a well-known device that acquires information about targets existing in front of the host vehicle HV using radio waves in the millimeter-wave band, and includes a radar 31 and a radar ECU 32. The radar 31 transmits millimeter waves within a predetermined detection range every time a predetermined time elapses, and receives the millimeter waves reflected by the target. The radar 31 transmits information about the transmitted and received millimeter waves to the radar ECU 32. The radar ECU 32 acquires radar information including "distance to the target, azimuth of the target, relative speed of the target, etc." based on the information from the radar 31, and transmits it to the driving support ECU 10. Note that the driving support ECU 10 generates fusion target information that finally identifies "position, relative speed, type, etc." of the target by integrating (fusing) the camera information and the radar information.

[0018] The power train ECU 40 controls a drive device including a power source of the host vehicle HV (not shown) by driving a power train actuator 41, thereby generating a driving force.

[0019] The brake ECU 50 controls a braking device of the host vehicle HV (not shown) by driving a brake actuator 51, thereby applying a braking force to the host vehicle HV. When receiving an instruction from the driving support ECU 10, the brake ECU 50 executes an automatic brake that automatically applies a braking force to the host vehicle HV by driving the brake actuator 51.

[0020] The steering ECU 60 controls a steering device of the host vehicle HV (not shown) by driving a steering motor 61, thereby changing the steering angle of the host vehicle HV.

[0021] The notification ECU (warning ECU) 70 is connected to a warning display device 71 disposed at a position visible from the driver's seat and a warning sound generating device 72 that generates a warning sound, and controls these in response to an instruction from the driving support ECU 10.

[0022] The navigation ECU 80 is connected to a GPS receiver 81, a map database 82 that stores map information, and a display (touch panel) 83 that displays touch buttons, and together with these, they constitute an in-vehicle navigation system. The navigation ECU 80 acquires the current position of the host vehicle HV based on the GPS signal received by the GPS receiver 81, and based on the acquired current position of the host vehicle HV and the map information stored in the map database 82, it provides route guidance to the destination input through the display 83.

[0023] The audio device 85 includes a "radio receiver, amplifier, control circuit, and speaker", not shown in the figure. The control circuit is equipped with a Bluetooth function. The audio device 85 is configured to display operation buttons on the display 83 via the navigation ECU 80. The audio device 85 outputs various sounds from the speaker in response to operations on the operation buttons displayed on the display 83.

[0024] The communication device 90 performs wireless communication with devices external to the host vehicle HV (such as roadside units and information management centers, etc.) and can acquire various information from the external devices. Furthermore, the communication device 90 has a Bluetooth function. The vehicle user can set the mobile phone CP and the communication device 90 to be in a communicable state by establishing a Bluetooth connection between the communication device 90 and a mobile device including the mobile phone CP, and then make a hands-free call. The communication device 90 causes operation buttons to be displayed on the display 83 via the navigation ECU 80. The user can perform operations including making a call (to the mobile phone CP) by operating the operation buttons displayed on the display 83. Furthermore, when the mobile phone CP that is Bluetooth-connected to the communication device 90 is in a state of receiving an incoming call signal (incoming call state), the communication device 90 can display a screen indicating this via the navigation ECU 80 on the display 83.

[0025] The driving support ECU 10 inputs the detection values (output values) of the following "sensors and switches". · An accelerator pedal operation amount sensor 91 that detects the accelerator pedal operation amount AP of the host vehicle HV. · A brake pedal operation amount sensor 92 that detects the brake pedal operation amount BP of the host vehicle HV. · A vehicle speed sensor 93 that detects the speed of the host vehicle HV (i.e., the own vehicle speed). · An operation switch 94 of the air conditioner of the host vehicle HV. The air conditioner of the host vehicle HV (not shown) adjusts the temperature inside the vehicle compartment, the air volume, etc. according to the operation of the operation switch 94. · A hazard switch 95 for simultaneously flashing all turn signals of the host vehicle HV.

[0026] (Outline of operation) When the driver operates the operation switch of the in-vehicle device (hereinafter referred to as "the first case"), the driver's attention to driving often decreases. The operation switches of the in-vehicle device include various touch-operated operation buttons displayed on the display 83, the operation switch 94 of the air conditioner, the hazard switch 95, etc. Further, when the driver makes a hands-free call using his / her own mobile phone CP and the communication device 90 (hereinafter referred to as "the second case"), the driver's attention to driving often decreases. In addition, when there is an incoming call to the mobile phone CP communicably connected to the communication device 90 (hereinafter referred to as "the third case"), since a display to that effect is made on the display 83, the driver's attention to driving often decreases. Therefore, in such cases, the device DS advances the timing of starting the collision avoidance support operation including an alarm earlier than the timing in cases other than such cases. Thereby, when the driver's attention to driving decreases, the driver can notice the presence of an obstacle at an early stage and can take appropriate measures against the obstacle.

[0027] (Specific operation) The CPU of the driving support ECU 10 (hereinafter simply referred to as "CPU") executes the routine shown by the flowchart in FIGS. 2 to 4 every time a predetermined time (calculation cycle) dt elapses. In the following, "step" is denoted as "S".

[0028] <Collision avoidance support> When a predetermined timing is reached, the CPU starts processing from S200 in FIG. 2 and proceeds to S205, and determines whether the value of the support flag XW is "0". When the value of the support flag is "1", it means that the collision avoidance support operation (first operation) is in progress. The value of the support flag XW and the value of the attention reduction flag Xd described later are set to "0" by an initialization routine (not shown) executed by the CPU when an activation switch (for example, an ignition key switch and a ready switch, etc.) of the host vehicle HV not shown is changed from the off position to the on position.

[0029] If the value of the support flag XW is "0", the CPU proceeds from S205 to S210, and determines whether there is an obstacle (target) in the area where the host vehicle HV will travel within a certain time (host vehicle travel area) based on the fusion target information (that is, camera information and radar information). If there is no target (obstacle) in the host vehicle travel area, the CPU proceeds directly from S210 to S295 and temporarily terminates this routine.

[0030] On the other hand, if there is an obstacle in the host vehicle travel area, the CPU proceeds from S210 to S215 and determines whether the value of the attention reduction flag Xd is "1". The attention reduction flag Xd is set to "1" when it is estimated that the driver's attention to driving has decreased (see FIG. 3 described later).

[0031] If the value of the attention reduction flag Xd is not "1" (that is, when it is "0"), the CPU determines "No" at S215 and proceeds to S220, and sets the collision determination threshold time TTCth to the basic threshold time TTCthB (see block B in FIG. 4). The basic threshold time TTCthB is a value set (changed) by the driver's operation. Next, the CPU proceeds from S220 to S225.

[0032] The CPU calculates the time to collision (TTC) at S225 by dividing the distance between the obstacle and the host vehicle HV by the relative speed of the obstacle. That is, the CPU calculates the time required until the host vehicle collides with the obstacle as the time to collision TTC. The time to collision TTC is a value that becomes smaller as the likelihood of the host vehicle HV colliding with the obstacle increases, and is one of the collision likelihood index values representing the collision likelihood between the host vehicle HV and the obstacle.

[0033] Next, the CPU proceeds to S230 and determines whether the time to collision TTC is less than or equal to the collision determination threshold time TTCth (in this case, the basic threshold time TTCthB). That is, the CPU determines at S230 whether the collision avoidance support start condition (warning generation condition) that holds when it is predicted that the host vehicle will collide with the target is satisfied. The collision avoidance support start condition is also referred to as the "first condition" for convenience.

[0034] If the time to collision TTC is not less than or equal to the collision determination threshold time TTCth, the CPU directly proceeds from S230 to S295 and temporarily ends this routine. On the other hand, if the time to collision TTC is less than or equal to the collision determination threshold time TTCth, the CPU proceeds from S230 to S235.

[0035] The CPU starts the warning generation operation (first operation) as the collision avoidance support operation. More specifically, the CPU transmits an instruction signal to the notification ECU 70 to cause the warning display device 71 to display a warning (attention - calling) mark and cause the warning sound generation device 72 to generate a warning sound. Next, the CPU proceeds to S240 and sets the value of the support flag XW to "1". Then, the CPU proceeds to S295.

[0036] On the other hand, when the CPU proceeds to S215 and the value of the inattentiveness flag Xd is "1", the CPU determines "Yes" at S215 and proceeds to S245. The CPU determines at S245 whether the type of the obstacle is "motorcycle or pedestrian". If the type of the obstacle is neither "motorcycle" nor "pedestrian", the CPU proceeds from S245 to S220 described above.

[0037] On the other hand, when the type of the obstacle is either "motorcycle and pedestrian", the CPU proceeds from S245 to S250. At S250, the CPU sets the collision determination threshold time TTCth to "a value obtained by adding a positive threshold correction value dTTCth (see S440 in FIG. 4) to the basic threshold time TTCthB". As a result, the first condition is changed to a first early establishment condition (TTC ≦ TTCthB + dTTCth) that is established earlier than the normal condition (TTC ≦ TTCthB). Note that, as will be described later, the process of S245 can be omitted.

[0038] As a result, when the collision required time TTC is less than or equal to the collision determination threshold time TTCth (in this case, TTCthB + threshold correction value dTTCth), it is determined that the collision avoidance support start condition (alarm generation condition, first condition) is satisfied, and the collision avoidance support operation (alarm generation operation, first operation) is started at S235. That is, when the value of the inattentiveness flag Xd is "1", the collision avoidance support operation is executed at an earlier timing than when the value of the inattentiveness flag Xd is not "1".

[0039] As can be understood from the above, when the value of the inattentiveness flag Xd is "1" and the obstacle is a motorcycle or a pedestrian, the first condition is changed to a first early establishment condition that is established at an earlier timing than when the value of the inattentiveness flag Xd is "0". Therefore, when the driver's attention to driving is reduced, the driver can recognize the obstacle earlier. Also, when the process of S245 is configured not to be executed, when the value of the inattentiveness flag Xd is "1", the first condition is changed to a first early establishment condition that is established at an earlier timing than when the value of the inattentiveness flag Xd is "0".

[0040] Incidentally, when the value of the support flag XW is set to "1" and the CPU proceeds to S205, the CPU proceeds from S205 to S255. At S255, the CPU determines whether there is a target (obstacle) in the host vehicle's traveling area. If there is a target (obstacle) in the host vehicle's traveling area, the CPU proceeds directly from S255 to S295. Therefore, in this case, the display of the warning mark and the generation of the warning sound continue.

[0041] On the other hand, when there is no longer a target (obstacle) in the host vehicle's traveling area, the CPU proceeds from S255 to S260 and sets the value of the support flag XW to "0". Next, the CPU proceeds from S260 to S265 and stops the warning generation operation as a collision avoidance support operation. After that, the CPU proceeds directly from S265 to S295 to temporarily end this routine.

[0042] <Setting of the inattentiveness flag> At a predetermined timing, the CPU starts processing from S300 in FIG. 3 and proceeds to S310 to determine whether the value of the inattentiveness flag Xd is "0".

[0043] If the value of the inattentiveness flag Xd is "0", the CPU proceeds from S310 to S320 and determines whether the current time is immediately after an operation on the in-vehicle device has been performed. Operations on the in-vehicle device include operations on the operation switch 94 of the air conditioner, operations on the hazard switch 95, and touch operations on various operation buttons displayed on the touch display 83.

[0044] If the current time is immediately after an operation on the in-vehicle device has been performed, the CPU proceeds from S320 to S330, sets the value of the inattentiveness flag Xd to "1", and then proceeds to S395. If the current time is not immediately after an operation on the in-vehicle device has been performed, the CPU proceeds from S320 to S340.

[0045] At S340, the CPU determines whether the user of the host vehicle including the driver is in the middle of making a hands-free call using the "mobile phone CP connected to the communication device 90 via Bluetooth" and the "communication device 90". If the user is in the middle of making a hands-free call, the CPU proceeds from S340 to S330, sets the value of the attention deficit flag Xd to "1", and then proceeds to S395. If the user is not in the middle of making a hands-free call, the CPU proceeds from S340 to S350.

[0046] At S350, the CPU determines whether the mobile phone CP connected to the communication device 90 via Bluetooth is receiving an incoming signal (i.e., is in an incoming call state). If it is in an incoming call state, the CPU proceeds from S350 to S330, sets the value of the attention deficit flag Xd to "1", and then proceeds to S395. If it is not in an incoming call state, the CPU proceeds from S350 to S395.

[0047] On the other hand, when the CPU proceeds to S310, if the value of the attention deficit flag Xd is "1", the CPU proceeds from S310 to S360 and determines whether a certain threshold time has elapsed since the last operation on the in-vehicle device. If the certain threshold time has not elapsed since the last operation on the in-vehicle device, the CPU proceeds directly from S360 to S395. Therefore, the value of the attention deficit flag Xd is maintained at "1".

[0048] In contrast, if the certain threshold time has elapsed since the last operation on the in-vehicle device, the CPU proceeds from S360 to S370 and determines whether the current state is a state where a hands-free call using the mobile phone CP and the communication device 90 is not being made. If the current state is a state where a hands-free call is being made (i.e., during a call), the CPU proceeds directly from S370 to S395. Therefore, the value of the attention deficit flag Xd is maintained at "1".

[0049] On the other hand, when the current state is a hands-free call not being made, the CPU proceeds from S370 to S380 and determines whether the current state is a state where an incoming signal is not being received by the "mobile phone CP Bluetooth-connected to the communication device 90". If the current state is a state where an incoming call is being received by the "mobile phone CP Bluetooth-connected to the communication device 90", the CPU proceeds directly from S380 to S395. Therefore, the value of the inattentiveness flag Xd is maintained at "1".

[0050] On the other hand, if the current state is not a state where an incoming call is being received by the "mobile phone CP Bluetooth-connected to the communication device 90", the CPU proceeds from S380 to S390. At S390, the CPU sets the value of the inattentiveness flag Xd to "0". Then, the CPU proceeds to S395.

[0051] <Determination of the basic threshold time and the threshold correction value> At a predetermined timing, the CPU starts processing from S400 in FIG. 4 and proceeds to S410, and determines whether the current time is "the time immediately after the time when the setting of the collision avoidance support timing is changed".

[0052] By the way, when a predetermined operation is performed on the touch display 83, the navigation ECU 80 displays a collision avoidance support timing selection screen 500 shown in FIG. 5 on the touch display 83. The selection screen 500 includes a button 511 displayed as "very early", a button 512 displayed as "early", a button 513 displayed as "normal", a button 514 displayed as "late", and a button 515 displayed as "very late". The driver can change and set the basic threshold time TTCthB in normal times (i.e., when the driver's attention to driving has not decreased) by performing a touch operation on one of these buttons, thereby setting the collision avoidance support timing. In the default state (initial state), the button 513 displayed as "normal" is automatically selected.

[0053] More specifically, when the driver performs a touch operation on one of buttons 511 to 515, the CPU determines "Yes" at S410 and proceeds to S420. At S420, the CPU refers to a look-up table LT stored in the ROM in advance and sets the basic threshold time TTCthB to a value corresponding to the button on which the touch operation was performed.

[0054] That is, when the button 511 displayed as "very early" is touched, the CPU sets the basic threshold time TTCthB to time T1. When the button 512 displayed as "early" is touched, the CPU sets the basic threshold time TTCthB to time T2. When the button 513 displayed as "normal" is touched, the CPU sets the basic threshold time TTCthB to time T3. When the button 514 displayed as "late" is touched, the CPU sets the basic threshold time TTCthB to time T4. When the button 515 displayed as "very late" is touched, the CPU sets the basic threshold time TTCthB to time T5. The following relationship of equation (1) holds among times T1 to T5. T1>T2>T3>T4>T5 ···(1)

[0055] Next, the CPU proceeds to S430 and obtains the value (T1 - TTCthB) obtained by subtracting the basic threshold time TTCthB from time T1 as the correction margin TS.

[0056] Next, the CPU proceeds to S440 and sets the threshold correction value dTTCth to the value (α·TS) obtained by multiplying the correction margin TS by the coefficient α. The coefficient α is a value greater than "0" and less than "1". Thereafter, the CPU proceeds to S495 and temporarily ends this routine. Note that the basic threshold time TTCthB, the correction margin TS, and the threshold correction value dTTCth are stored in the non-volatile memory of the driving support ECU100.

[0057] When the CPU advances to S410, if it is not immediately after a touch operation has been performed on any one of buttons 511 to 515 at that time, the CPU directly advances from S410 to S495 and temporarily ends this routine.

[0058] As described above, when the driver's attention to driving is reduced, the device DS starts the collision avoidance support operation (first operation) earlier, so the possibility of a collision between the host vehicle HV and an obstacle can be reduced. In particular, when the obstacle is either a two-wheeled vehicle or a pedestrian, the alarm operation as the collision avoidance support operation is started earlier, so the driver can recognize these obstacles earlier and start appropriate driving for them.

[0059] Note that the present invention is not limited to the above-described embodiments and modifications, and various modifications can be adopted within the scope of the present invention. For example, the process of S245 in FIG. 2 may be omitted. In this case, when the CPU determines "Yes" at S215, it advances to S250. Further, the CPU may execute an automatic brake as a collision avoidance support operation in addition to the alarm operation as the collision avoidance support operation at S235.

[0060] Furthermore, the CPU according to a modification of the driving support ECU 10 may execute the routine shown in FIG. 6 instead of the routine shown in FIG. 2. In FIG. 6, some of the steps that are the same as the steps shown in FIG. 2 are given the same reference numerals as the reference numerals given to the steps shown in FIG. 2. The description of these steps is omitted.

[0061] That is, when the CPU determines that there is an obstacle at S210 in FIG. 6, it determines whether the attention reduction flag Xd is "1" at S605. If the attention reduction flag Xd is "1", the CPU proceeds from S605 to S610 and sets the automatic braking threshold time TTCBth to "the sum of the basic threshold time TTCthB and the above-described threshold correction value dTTCth". Thereafter, the CPU proceeds to S620. On the other hand, if the attention reduction flag Xd is not "1", the CPU proceeds from S605 to S615 and sets the automatic braking threshold time TTCBth to the basic threshold time TTCthB. Thereafter, the CPU proceeds to S630.

[0062] At S620, the CPU determines whether the type of the obstacle is "motorcycle or pedestrian". If the type of the obstacle is either "motorcycle or pedestrian", the CPU proceeds from S620 to S625 and sets the warning threshold time TTCWth to "the sum of the basic threshold time TTCthB, a positive fixed time TW, and the above-described threshold correction value dTTCth". Thereafter, the CPU proceeds to S635. On the other hand, if the type of the obstacle is neither "motorcycle nor pedestrian", the CPU proceeds from S620 to S630 and sets the warning threshold time TTCWth to "the sum of the basic threshold time TTCthB and the fixed time TW". Thereafter, the CPU proceeds to S635.

[0063] At S635, the CPU calculates the time to collision TTC, and at S640, determines whether the time to collision TTC is less than or equal to the warning threshold time TTCWth. If the time to collision TTC is less than or equal to the warning threshold time TTCWth, the CPU executes the above-described warning operation at S645. Thereafter, the CPU proceeds to S650. If the time to collision TTC is not less than or equal to the warning threshold time TTCWth, the CPU proceeds directly from S640 to S650.

[0064] The CPU determines whether the time to collision TTC at S650 is less than or equal to the automatic braking threshold time TTCBth. When the time to collision TTC is less than or equal to the automatic braking threshold time TTCBth, the automatic braking start condition as a collision avoidance support start condition is satisfied. The automatic braking start condition is also referred to as the "second condition" for convenience. As understood from the above, when the inattentiveness flag Xd is "1", the second condition is changed to a second early satisfaction condition that is satisfied earlier than when the inattentiveness flag Xd is "0" (see S610, S615, and S650).

[0065] When the time to collision TTC is less than or equal to the automatic braking threshold time TTCBth, the CPU starts the above-described automatic braking at S655. Thereafter, the CPU sets the value of the support flag XW to "1" at S660 and proceeds to S695 to temporarily end this routine. When the time to collision TTC is not less than or equal to the automatic braking threshold time TTCBth, the CPU directly proceeds from S650 to S695 to temporarily end this routine.

[0066] As described above, in the case of the CPU of the modified example, when the inattentiveness flag Xd is "1", regardless of the type of the obstacle, the start condition of the automatic braking is changed to a condition that is satisfied earlier than when the inattentiveness flag Xd is not "1". When the inattentiveness flag Xd is "1", the CPU changes the warning generation condition to a condition that is satisfied earlier than when the inattentiveness flag Xd is not "1", only when the obstacle is either a two-wheeled vehicle or a pedestrian.

[0067] In addition, the CPU according to the above-described embodiment and modification example may execute only any one or two steps among "S320, S340, and S350" between S310 and S330 in FIG. 3, and when the determination condition for the executed step is satisfied, it may proceed to S330 and set the attention decrease flag Xd to "1". In this configuration, S360 is omitted when S320 is not executed, S370 is omitted when S340 is not executed, and S380 is omitted when S350 is not executed. That is, when at least one case among any one or more combinations of the above first to third cases occurs (that is, when a specific state occurs), the CPU estimates that the driver's attention to driving has decreased, and compared with the case where none of the combinations have occurred (that is, when the specific state has not occurred), the conditions (first conditions) necessary for starting the collision avoidance support operation (first operation) may be changed to "conditions that are satisfied earlier (first early satisfaction conditions)".

[0068] Further, the CPU may set the collision determination threshold time TTCth to "a value obtained by adding the correction margin TS to the basic threshold time TTCthB" at S255, and when it determines "No" at S245, set the collision determination threshold time TTCth to "a value obtained by adding the threshold correction value dTTCth to the basic threshold time TTCthB", and then proceed to S225. Furthermore, the collision possibility index value may be the reciprocal of the collision required time TTC. In that case, the first condition is satisfied when the collision possibility index value reaches the first threshold, and the second condition is satisfied when the collision possibility index value reaches the second threshold that is greater than the first threshold. In addition, the present invention is applicable to the host vehicle HV in a state where the driving mode has transitioned from automatic driving to driving by the driver in an autonomous vehicle.

Explanation of Signs

[0069] 10... Driving support ECU, 83... Display, 85... Audio device, 90... Communication device, 94... Air conditioner operation switch, 95... Hazard switch.

Claims

1. In a vehicle collision avoidance support device including a controller configured to start a first operation for avoiding a collision between the host vehicle and a target object when a first condition that holds when there is a high possibility of the host vehicle colliding with the target object is satisfied, the controller, when a specific state including at least one of a state in which it is presumed that the user of the host vehicle is operating on-vehicle equipment mounted on the host vehicle, a state in which the user is making a call using the on-vehicle equipment and a portable device communicably connected to the on-vehicle equipment, and a state in which the portable device communicably connected to the on-vehicle equipment is receiving an incoming signal occurs, changes the first condition to a first early establishment condition that is a condition that is satisfied earlier than when the specific state does not occur. configured as follows, A vehicle collision avoidance support device.

2. In the vehicle collision avoidance support device according to claim 1, the controller is configured to perform, as the first operation, an operation of generating an alarm for the driver of the host vehicle, and is configured not to change the first condition to the first early establishment condition even when the specific state occurs when the target object is neither a two-wheeled vehicle nor a pedestrian. A vehicle collision avoidance support device.

3. In the vehicle collision avoidance support device according to claim 2, the controller, when a second condition that holds when the possibility of the host vehicle colliding with the target object becomes higher than when the first condition is satisfied is satisfied, is configured to execute an automatic brake for avoiding a collision between the host vehicle and the target object, when the specific state occurs, is configured to change the second condition to a second early establishment condition that is a condition that is satisfied earlier than when the specific state does not occur, regardless of the type of the target object. A vehicle collision avoidance support device.

4. When a first condition that holds when there is a high possibility of the host vehicle colliding with a target object is satisfied, a step of starting a first operation for avoiding a collision between the host vehicle and the target object; When a specific state including at least one of the following states occurs: a state in which it is estimated that the user of the host vehicle is operating on-vehicle equipment mounted on the host vehicle; a state in which the user is making a call using the on-vehicle equipment and a portable device communicably connected to the on-vehicle equipment; and a state in which the portable device communicably connected to the on-vehicle equipment is receiving an incoming signal, a step of changing the first condition to a condition that is satisfied earlier than when the specific state does not occur; comprising: A method for assisting in avoiding a collision of a vehicle.

5. A program to be executed by a computer mounted on a host vehicle, the program causes the computer to when a first condition that is satisfied when there is a high possibility that the host vehicle will collide with an object is satisfied, start a first operation to avoid a collision between the host vehicle and the object; when a specific state including at least one of the following states occurs: a state in which it is estimated that the user of the host vehicle is operating on-vehicle equipment mounted on the host vehicle; a state in which the user is making a call using the on-vehicle equipment and a portable device communicably connected to the on-vehicle equipment; and a state in which the portable device communicably connected to the on-vehicle equipment is receiving an incoming signal, a step of changing the first condition to a condition that is satisfied earlier than when the specific state does not occur; A program to be executed.

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