Driving assistance device, driving assistance method, and program

Abstract

To provide a technique capable of appropriately performing driving assistance for a self-vehicle.SOLUTION: A driving assistance device includes: storage means that stores a plurality of intersection locations each indicating a location where a traveling trajectory of a self-vehicle and a traveling trajectory of another vehicle intersect in the past; acquisition means that acquires surrounding vehicle information of a surrounding vehicle through vehicle-to-vehicle communication; prediction means that predicts a possibility of collision between the self-vehicle and the surrounding vehicle in a target area in front of the self-vehicle on the basis of self-vehicle information and the surrounding vehicle information; and assistance means that performs driving assistance for the self-vehicle on the basis of a prediction result by the prediction means. The prediction means predicts, in a case where none of the plurality of intersection locations is present within a predetermined distance in front of the self-vehicle, the possibility of collision by setting the target area to a first area, and predicts, in a case where at least one intersection location of the plurality of intersection locations is present within the predetermined distance, the possibility of collision by setting the target area to a second area larger than the first area.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a driving assistance device, a driving assistance method, and a program. [Background technology]

[0002] There is known a device that performs driving assistance without using map information to prevent a collision with another vehicle (surrounding vehicle), etc. Patent Document 1 discloses a driving assistance device that registers in a storage unit position information of an intersection where the travel path of the vehicle and the travel path of another vehicle intersect, and performs driving assistance for the vehicle when passing through the intersection again. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 7054636 Summary of the Invention [Problem to be solved by the invention]

[0004] The driving assistance device can predict the possibility of collision of the vehicle within a target area in front of the vehicle and provide driving assistance for the vehicle based on the prediction result. However, for example, when entering a main road including multiple lanes, even if an intersection position (intersection) where the driving trajectory of the vehicle and the driving trajectory of another vehicle in the past intersected with each other is stored for the main road, the intersection position may not be included in the target area where the driving assistance is provided, and driving assistance may not be provided appropriately.

[0005] Therefore, an object of the present invention is to provide a technique capable of appropriately performing driving assistance for a vehicle. [Means for solving the problem]

[0006] In order to achieve the above object, a driving assistance device according to one aspect of the present invention includes a storage means for storing a plurality of intersection positions each indicating a position where a travel path of the host vehicle and a travel path of another vehicle have intersected in the past, an acquisition means for acquiring surrounding vehicle information including a current position, a speed, and a travel path of the surrounding vehicle present around the host vehicle from the surrounding vehicle by vehicle-to-vehicle communication, a prediction means for predicting a possibility of a collision between the host vehicle and the surrounding vehicle within a target area ahead of the host vehicle based on the host vehicle information including the current position, the speed, and the travel path of the host vehicle and the surrounding vehicle information acquired by the acquisition means, and and an assistance means for providing driving assistance for the host vehicle, including at least one of alerting an occupant of the host vehicle and providing deceleration assistance for the host vehicle based on a prediction result by the prediction means, wherein the prediction means predicts the possibility of collision by setting the target area to a first area when none of the plurality of intersection positions stored in the storage means is present within a predetermined distance ahead of the host vehicle, and predicts the possibility of collision by setting the target area to a second area larger than the first area when at least one of the plurality of intersection positions stored in the storage means is present within the predetermined distance. Effect of the Invention

[0007] According to the present invention, for example, it is possible to provide a technique that is capable of appropriately performing driving assistance for a vehicle. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a diagram showing an example of the configuration of a driving support device according to an embodiment of the present invention; [Diagram 2] A diagram showing an example of the configuration of an intersection position database. [Diagram 3] Diagram for explaining the intersection position [Figure 4] FIG. 1 is a diagram for explaining problems with a conventional driving assistance device. [Diagram 5] FIG. 1 is a diagram for explaining changes in the dimensions of a target area for providing driving assistance to a host vehicle; [Figure 6]A flowchart showing a driving assistance process according to an embodiment of the present invention. [Figure 7] Flowchart showing a method for predicting a collision possibility of a host vehicle (first embodiment) [Figure 8] FIG. 1 is a diagram for explaining a method for predicting a collision possibility in the first embodiment. [Figure 9] A diagram showing the relationship between the speed of surrounding vehicles and their stopping time [Figure 10] Flowchart showing a method for predicting a collision possibility of a host vehicle (embodiment 2) [Figure 11] FIG. 11 is a diagram for explaining a method for predicting a collision possibility in the second embodiment. [Figure 12] Flowchart showing a method for predicting a collision possibility of a host vehicle (third embodiment) [Figure 13] FIG. 13 is a diagram for explaining a method for predicting a collision possibility in the third embodiment. [Figure 14] Flowchart showing a method for registering a new intersection position [Figure 15] FIG. 2 is a diagram for explaining an intersection between a host vehicle and a surrounding vehicle; [Figure 16] FIG. 1 is a diagram for explaining registration of driving trajectories (passing points) of surrounding vehicles; DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. The present invention is not limited to the following embodiment, and includes changes and modifications of the configuration within the scope of the present invention. Furthermore, not all of the combinations of features described in the present embodiment are necessarily essential to the present invention. Note that the same components are given the same reference numbers and their description will be omitted.

[0010] <Configuration of driving support device> FIG. 1 is a diagram showing an example of the configuration of a driving support device 100 according to an embodiment of the present invention. The driving support device 100 is a device mounted on a vehicle to provide driving support for the vehicle. In this embodiment, the driving support device 100 performs collision prevention support for preventing (reducing) collisions with surrounding vehicles as driving support for the vehicle without using map information. The driving support device 100 of this embodiment may include a sensor group 11, a GNSS (Global Navigation Satellite System) antenna 12, a vehicle-to-vehicle communication antenna 13, a notification device 14, a braking device 15, and a control device 20. In the following description, the term "other vehicle" refers to a vehicle other than the vehicle, and may be specifically defined as a vehicle with which vehicle-to-vehicle communication has been performed with the vehicle. The term "surrounding vehicle" refers to a vehicle currently present in the vicinity of the vehicle, and may be specifically defined as a vehicle with which vehicle-to-vehicle communication has been performed with the vehicle.

[0011] The sensor group 11 includes various sensors mounted on the host vehicle to perform driving assistance for the host vehicle. For example, the sensor group 11 may include a speed sensor that detects the speed of the host vehicle, an acceleration sensor that detects the acceleration of the host vehicle, and the like. The sensor group 11 may also include external detection sensors such as a camera, a millimeter wave radar, and a lidar (Light Detection and Ranging: LIDAR) that can detect objects around the host vehicle. The sensor group 11 outputs the detection results to the control device 20.

[0012] The GNSS antenna 12 receives radio waves for position measurement transmitted from GNSS satellites. For example, the GNSS antenna 12 can be used to obtain information about the current position of the vehicle. The vehicle-to-vehicle communication antenna 13 is an antenna that transmits and receives various data to and from surrounding vehicles. For example, the vehicle-to-vehicle communication antenna 13 can be used to obtain information about the current positions, speeds, and driving trajectories of surrounding vehicles.

[0013] The notification device 14 is a device that notifies the occupants of the vehicle (e.g., the driver). When there is a possibility that the vehicle will collide with a surrounding vehicle, the driving assistance device 100 of this embodiment can notify the occupants of the vehicle of the possibility of a collision with the surrounding vehicle by the notification device 14 as driving assistance. For example, the notification device 14 may include a display unit such as a display and display information indicating the possibility of a collision with the surrounding vehicle on the display unit, or may include an audio output unit such as a speaker and output information indicating the possibility of a collision with the surrounding vehicle from the audio output unit by voice or the like.

[0014] The braking device 15 is a device for performing a braking operation of the host vehicle, such as a brake. When there is a possibility that the host vehicle will collide with a surrounding vehicle, the driving assistance device 100 of the present embodiment can operate the braking device 15 to assist in decelerating the host vehicle as driving assistance, thereby avoiding a collision with the surrounding vehicle.

[0015] The control device 20 is a device (computer) that controls driving assistance for the vehicle, and may be configured, for example, by an ECU (Electric Control Unit). The control device 20 of this embodiment performs driving assistance through inter-vehicle communication with other vehicles (surrounding vehicles) and processing within the vehicle. That is, the control device 20 performs driving assistance without using map information. The control device 20 includes a processing unit 21, a storage unit 22, a GNSS module 23, and an inter-vehicle communication module 24, which are connected by a bus (not shown).

[0016] The processing unit 21 is a processor represented by a CPU (Central Processing Unit), and executes a program stored in the storage unit 22. The storage unit 22 includes, for example, a RAM, a ROM, a hard disk, etc., and stores various data in addition to a program (driving assistance program) for the processing unit 21 to execute driving assistance processing of the vehicle. In the case of this embodiment, the storage unit 22 stores a database (information) of multiple intersection positions indicating positions where the traveling trajectory of the vehicle and the traveling trajectory of another vehicle have intersected in the past. In addition, the GNSS module 23 receives position information of the vehicle from a GNSS satellite via the GNSS antenna 12. In addition, the vehicle-to-vehicle communication module 24 receives various information from another vehicle via the vehicle-to-vehicle communication antenna 13.

[0017] The processing unit 21 of this embodiment may include an acquisition unit 21a, a prediction unit 21b, a driving support unit 21c, a specification unit 21d, and a registration unit 21e in order to execute driving support for the host vehicle (collision prevention support in this embodiment). Note that the processing unit 21 is not limited to a configuration including each of the units 21a to 21e, and other units may be added or some units may be omitted depending on the type of driving support executed in the host vehicle.

[0018] The acquisition unit 21a acquires surrounding vehicle information including the current position, speed, and traveling trajectory of the surrounding vehicle from the surrounding vehicle via the vehicle-to-vehicle communication antenna 13 (vehicle-to-vehicle communication module 24). The acquisition unit 21a may also include a function of acquiring host vehicle information including the current position, speed, and traveling trajectory of the host vehicle via the sensor group 11 and the GNSS antenna 12 (GNSS module 23).

[0019] The prediction unit 21b predicts the possibility of collision of the host vehicle within a target area in front of the host vehicle based on the host vehicle information and the surrounding vehicle information acquired by the acquisition unit 21a. The target area, the details of which will be described later, may be understood as an area (driving assistance area) for which driving assistance is performed to prevent a collision between the host vehicle and the surrounding vehicles. The driving assistance unit 21c performs driving assistance to prevent a collision between the host vehicle and the surrounding vehicles based on the prediction result by the prediction unit 21b. In this embodiment, the driving assistance unit 21c can execute at least one of the following as driving assistance for the host vehicle: a notification to the occupants of the host vehicle by the notification device 14, and deceleration assistance for the host vehicle by the braking device 15.

[0020] The identification unit 21d identifies a position where the host vehicle and the surrounding vehicles intersect as a new intersection position based on the host vehicle information and the surrounding vehicle information acquired by the acquisition unit 21a. When the identification unit 21d identifies a new intersection position, the registration unit 21e registers the new intersection position identified by the identification unit 21d in the storage unit 22 (a database of multiple intersection positions).

[0021] Next, a database of multiple intersection positions stored in storage unit 22 will be described. Fig. 2 shows an example of the configuration of the database of multiple intersection positions stored in storage unit 22. In addition, hereinafter, the database of multiple intersection positions stored in storage unit 22 may be referred to as an "intersection position database", and an intersection position registered in the intersection position database may be referred to as a "registered intersection position". Note that the intersection position database shown in Fig. 2 is merely an example, and items included in the intersection position database can be changed as appropriate.

[0022] The intersection position database may include information regarding an intersection position ID, a registration date and time, coordinates, and a passing direction for each registered intersection position. The intersection position ID is an identification number for each registered intersection position. The registration date and time is the date and time when the registered intersection position is registered in the intersection position database. The coordinates are data for identifying the registered intersection position, and are represented by, for example, latitude and longitude data. The coordinates may include altitude data such as altitude in addition to the latitude and longitude data. The passing direction is the direction (direction, angle) in which the host vehicle was facing when passing the registered intersection position. In this embodiment, the passing direction of the host vehicle at the registered intersection position is specified by defining north as 0°, east as 90°, south as 180°, and west as 270°.

[0023] Here, the intersection position will be described with reference to Fig. 3. Fig. 3 is a diagram for explaining the intersection position. As described above, the intersection position is a position where the travel path of the vehicle and the travel path of another vehicle have crossed in the past. Note that, although the present embodiment will be described by taking right-hand traffic as an example, the same applies to left-hand traffic.

[0024] In the example shown in FIG. 3(a), the position where the travel trajectory 31a of the host vehicle SV traveling straight north and the travel trajectory 32a of the other vehicle OVA traveling straight west intersect is identified as the "intersection position CPa" and registered in the intersection position database of the storage unit 22. Note that the timing (time) at which the host vehicle SV passes the intersection position CPa is different from the timing (time) at which the other vehicle OVA passes the intersection position CPa, so no collision occurs between the host vehicle SV and the other vehicle OVA. In addition, the travel trajectory 31a of the host vehicle SV is included in the host vehicle information acquired by the acquisition unit 21a via the sensor group 11 and the GNSS antenna 12 (GNSS module 23). The travel trajectory 32a of the other vehicle OVA is included in the other vehicle information acquired by the acquisition unit 21a via the vehicle-to-vehicle communication antenna 13 (vehicle-to-vehicle communication module 24). The other vehicle information may be understood as surrounding vehicle information because the other vehicle OVA is a surrounding vehicle present around the host vehicle SV at the time of acquisition.

[0025] In the example shown in FIG. 3(b), the position where the travel trajectory 31b of the host vehicle SV that traveled straight north and turned left and the travel trajectory 32b of the other vehicle OVb that traveled straight south intersect is identified as the "intersection position CPb" and registered in the intersection position database of the storage unit 22. Note that the timing (time) at which the host vehicle SV passes the intersection position CPb is different from the timing (time) at which the other vehicle OVb passes the intersection position CPb, so no collision occurs between the host vehicle SV and the other vehicle OVb. Similarly to the travel trajectory 31a, the travel trajectory 31b of the host vehicle SV is included in the host vehicle information acquired by the acquisition unit 21a via the sensor group 11 and the GNSS antenna 12 (GNSS module 23). Similarly to the travel trajectory 32a, the travel trajectory 32b of the other vehicle OVb is included in the other vehicle information (nearby vehicle information) acquired by the acquisition unit 21a via the vehicle-to-vehicle communication antenna 13 (vehicle-to-vehicle communication module 24).

[0026] The functions of the control device 20 can be realized by either hardware or software. For example, the functions of the control device 20 may be realized by the processing unit 21 (CPU) executing a driving assistance program as described above, or may be realized by a known semiconductor device such as a PLD (Programmable Logic Device) or an ASIC (Application Specific Integrated Circuit). In the present embodiment, the control device 20 is shown as a single element, but may be divided into two or more elements as necessary.

[0027] Incidentally, the processing unit 21 (prediction unit 21b, driving assistance unit 21c) in the driving assistance device 100 predicts the possibility of collision of the host vehicle SV within a target area TA ahead of the host vehicle SV as described above, and performs driving assistance for the host vehicle SV based on the prediction result. However, for example, when entering a trunk road including multiple lanes, as shown in Fig. 4, even if a registered intersection position CP exists on the trunk road, the registered intersection position CP may not be included in the target area TA where driving assistance is performed, and driving assistance may not be performed appropriately.

[0028] Therefore, as shown in FIG. 5(a), when none of the multiple registered intersection positions stored in the storage unit 22 exists within a predetermined distance D ahead of the host vehicle SV, the driving assistance device 100 of this embodiment sets the target area TA to a first area TA1 and performs driving assistance for the host vehicle SV. On the other hand, as shown in FIG. 5(b), when at least one registered intersection position CP of the multiple registered intersection positions stored in the storage unit 22 exists within a predetermined distance D ahead of the host vehicle SV, the driving assistance device 100 sets the target area TA to a second area TA2 and performs driving assistance for the host vehicle SV. The second area TA2 is an area larger than the first area TA1, and is set to be longer than the first area TA1 at least in the traveling direction of the host vehicle SV. The second area TA2 may be set to be longer than the first area TA1 in the vehicle width direction of the host vehicle SV. The predetermined distance D may be understood as a predetermined range (search range) for searching for the registered intersection position CP ahead of the host vehicle SV. The predetermined distance D can be set arbitrarily, but for example, can be set to a distance (range) that can cover the maximum road width expected for a trunk road including multiple lanes.

[0029] <Driving assistance processing> The driving assistance process of this embodiment will be described below. Fig. 6 is a flowchart showing the driving assistance process of this embodiment. The driving assistance process shown in the flowchart of Fig. 6 is executed by the processing unit 21 in the driving assistance device 100 according to a driving assistance program read from the storage unit 22. The flowchart of Fig. 6 can be repeatedly executed, for example, until the driving assistance setting is turned off or the ignition of the host vehicle SV is turned off.

[0030] In step S101, the processing unit 21 (prediction unit 21b) refers to a plurality of registered intersection positions CP stored in the storage unit 22 to determine whether or not a registered intersection position CP exists within a predetermined area D ahead of the vehicle SV. For example, the processing unit 21 can determine whether or not a registered intersection position CP exists within a predetermined area D ahead of the vehicle SV by comparing the current position of the vehicle SV acquired by the acquisition unit 21a via the GNSS antenna 12 (GNSS module 23) with the coordinates (latitude, longitude) of each registered intersection position CP stored in the storage unit 22. If the registered intersection position CP does not exist within the predetermined area D, the process proceeds to step S102, where the processing unit 21 (prediction unit 21b) sets the target area TA for performing driving assistance ahead of the vehicle SV to a first area TA1. On the other hand, if the registered intersection position CP exists within the predetermined area D, the process proceeds to step S103, where the processing unit 21 (prediction unit 21b) sets the target area TA to a second area TA2. That is, the processing unit 21 changes the target area TA from the first area TA1 to the second area TA2.

[0031] In step S104, the processing unit 21 determines whether or not there is a surrounding vehicle RV. As described above, the surrounding vehicle RV is a vehicle that is currently present around the host vehicle SV. For example, the processing unit 21 can determine that there is a surrounding vehicle RV when vehicle-to-vehicle communication can be performed via the vehicle-to-vehicle communication antenna 13 (vehicle-to-vehicle communication module 24). If it is determined that there is no surrounding vehicle RV, the processing unit 21 proceeds to step S101, and if it is determined that there is a surrounding vehicle RV, the processing unit 21 proceeds to step S105.

[0032] In step S105, the processing unit 21 (acquisition unit 21a) acquires the host vehicle information and the surrounding vehicle information. For example, the processing unit 21 acquires the surrounding vehicle information including the current position, speed, and traveling trajectory of the surrounding vehicle RV from the surrounding vehicle RV via the vehicle-to-vehicle communication antenna 13 (vehicle-to-vehicle communication module 24). The processing unit 21 also acquires the host vehicle information including the current position, speed, and traveling trajectory of the host vehicle SV via the sensor group 11 and the GNSS antenna 12 (GNSS module 23).

[0033] In step S106, the processing unit 21 (prediction unit 21b) predicts the possibility of a collision between the host vehicle SV and the surrounding vehicle RV in the target area TA based on the host vehicle information and the surrounding vehicle information acquired in step S105. The target area TA in which the prediction of the possibility of a collision between the host vehicle SV and the surrounding vehicle RV is performed is set to the first area TA1 in step S102 or the second area TA2 in step S103. The prediction of the possibility of a collision in the target area TA will be described in detail later.

[0034] In step S107, the processing unit 21 (driving support unit 21c) determines whether or not there is a possibility of a collision between the host vehicle SV and the surrounding vehicle RV based on the prediction result in step S106. If it is determined that there is no possibility of a collision, the process proceeds to step S101, and if it is determined that there is a possibility of a collision, the process proceeds to step S108.

[0035] In step S108, the processing unit 21 (driving support unit 21c) determines whether the speed of the surrounding vehicle RV is within a specified range based on the surrounding vehicle information acquired in step S105. The specified range may be set in advance by a lower limit speed value and an upper limit speed value related to the speed of the surrounding vehicle RV. If the speed of the surrounding vehicle RV is equal to or lower than the lower limit speed value of the specified range, the driver of the surrounding vehicle RV is likely to notice the host vehicle SV and decelerate the surrounding vehicle RV without colliding with the host vehicle SV. In other words, the lower limit speed value of the specified range related to the speed of the surrounding vehicle RV may be set to a value that allows the surrounding vehicle RV to decelerate without colliding with the host vehicle SV. In addition, if the speed of the surrounding vehicle RV is equal to or higher than the upper limit speed value of the specified range, the surrounding vehicle RV is likely not a vehicle traveling on the road into which the host vehicle SV enters, such as traveling on an expressway near the road into which the host vehicle SV enters. In other words, the upper limit of the specified range regarding the speed of the surrounding vehicle RV can be set to a value that makes it possible to distinguish whether the surrounding vehicle RV is traveling on the road into which the host vehicle SV is entering, or is traveling on an expressway near the road. In this way, by executing / suppressing driving assistance depending on whether the speed of the surrounding vehicle RV is within the specified range, it is possible to reduce the annoyance felt by the driver of the host vehicle SV due to the driving assistance.

[0036] If it is determined in step S108 that the speed of the surrounding vehicle RV is not within a specified range, i.e., is outside the specified range, the process proceeds to step S101. That is, in the case of this embodiment, the processing unit 21 does not perform driving assistance for the host vehicle SV when the speed of the surrounding vehicle RV is outside the specified range, regardless of the collision possibility predicted in steps S106 to S107. On the other hand, if it is determined that the speed of the surrounding vehicle RV is within the specified range, the process proceeds to step S109, and the processing unit 21 (driving assistance unit 21c) performs driving assistance for the host vehicle SV. As driving assistance for the host vehicle SV, the processing unit 21 may notify the occupants of the host vehicle SV of the possibility of a collision using the alarm device 14, or perform a braking operation for the host vehicle SV using the braking device 15.

[0037] <Method of predicting the possibility of collision> Next, a method for predicting the collision possibility of the host vehicle SV in the above step S106 will be described. Examples 1 to 3 are given as examples of the collision possibility prediction method. The processing unit 21 can predict the collision possibility of the host vehicle SV using a prediction method of an embodiment selected from Examples 1 to 3 according to the situation and settings.

[0038] [Example 1] A first embodiment of a method for predicting the collision possibility of the host vehicle SV will be described below. In the first embodiment, an example of predicting the collision possibility of the host vehicle SV using a time to collision (TTC: Time To Collision) will be described. FIG. 7 is a flowchart showing a method (first embodiment) for predicting the collision possibility of the host vehicle SV in step S106. The flowchart in FIG. 7 can be executed by the processing unit 21 (prediction unit 21b). Also, FIG. 8 is a diagram for explaining the method for predicting the collision possibility in the first embodiment.

[0039] In step S201, the processing unit 21 estimates a route along which the host vehicle SV will travel in the future (future travel route) based on the host vehicle information acquired in step S105. For example, as shown in Fig. 8, the processing unit 21 can estimate a future travel route 41b of the host vehicle SV by extending a past travel trajectory 41a of the host vehicle SV included in the host vehicle information along the past travel trajectory 41a.

[0040] In step S202, the processing unit 21 estimates a route (future travel route) along which the surrounding vehicle RV will travel in the future, based on the surrounding vehicle information acquired in step S105. For example, as shown in Fig. 8, the processing unit 21 can estimate a future travel route 42b of the surrounding vehicle RV by extending a past travel trajectory 42a of the surrounding vehicle RV included in the surrounding vehicle information along the travel trajectory 42a.

[0041] In step S203, the processing unit 21 determines whether the future travel path 41b of the host vehicle SV estimated in step S201 intersects with the future travel path 42b of the surrounding vehicle RV estimated in step S202. If it is determined that the future travel path 41b of the host vehicle SV and the future travel path 42b of the surrounding vehicle RV do not intersect, the process proceeds to step S209, and the processing unit 21 determines that there is no possibility of a collision between the host vehicle SV and the surrounding vehicle RV, and then proceeds to step S107 in the flowchart of Fig. 6. On the other hand, if it is determined that the future travel path 41b of the host vehicle SV and the future travel path 42b of the surrounding vehicle RV intersect, the process proceeds to step S204.

[0042] In step S204, the processing unit 21 obtains a position where the future travel path 41b of the host vehicle SV estimated in step S201 intersects with the future travel path 42b of the peripheral vehicle RV estimated in step S202 as an estimated intersection position CPe. The estimated intersection position CPe is a position where the host vehicle SV and the peripheral vehicle RV pass through in common, and when the estimated intersection position CPe is within the target area TA, it can be determined that the host vehicle SV and the peripheral vehicle RV may collide at the estimated intersection position CPe. As described above, the target area TA is an area (driving assistance area) where driving assistance is performed to prevent a collision between the host vehicle SV and the peripheral vehicle RV, and is set to the first area TA1 in step S102 or the second area TA2 in step S103 of the flowchart in FIG. 6.

[0043] In step S205, the processing unit 21 judges whether or not the estimated intersection position CPe obtained in step S204 is within the target area TA. If it is judged that the estimated intersection position CPe is not within the target area TA, the process proceeds to step S209, where the processing unit 21 judges that there is no possibility of a collision between the host vehicle SV and the surrounding vehicle RV, and then proceeds to step S107 in the flowchart of Fig. 6. On the other hand, if it is judged that the estimated intersection position CPe is within the target area TA, the process proceeds to step S206. Note that Fig. 8 shows an example in which the estimated intersection position CPe is within the target area TA.

[0044] In step S206, the processing unit 21 predicts, as a collision possibility, an arrival time required for the surrounding vehicle RV to reach the estimated intersection position CPe, based on the surrounding vehicle information acquired in step S105. For example, the processing unit 21 can predict the arrival time (hereinafter, sometimes simply referred to as "arrival time") of the surrounding vehicle RV to the estimated intersection position CPe, by dividing the distance between the surrounding vehicle RV and the estimated intersection position CPe by the speed of the surrounding vehicle RV, based on the current position and speed of the surrounding vehicle RV included in the surrounding vehicle information.

[0045] In step S207, the processing unit 21 determines whether the arrival time obtained in step S206 is equal to or less than a time threshold value. The time threshold value can be set by an occupant of the host vehicle SV. If the arrival time is equal to or less than the time threshold value, the process proceeds to step S208, where the processing unit 21 determines that there is a possibility of a collision between the host vehicle SV and the surrounding vehicle RV, and then proceeds to step S107 in the flowchart of FIG. 6. On the other hand, if the arrival time is greater than the time threshold value, the process proceeds to step S209, where the processing unit 21 determines that there is no possibility of a collision between the host vehicle SV and the surrounding vehicle RV, and then proceeds to step S107 in the flowchart of FIG. 6.

[0046] Here, the processing unit 21 may change the time threshold value according to the speed of the surrounding vehicle RV included in the surrounding vehicle information. FIG. 9 is a diagram showing the relationship between the speed of the surrounding vehicle RV and the stopping time of the surrounding vehicle RV. The stopping time of the surrounding vehicle RV is the time it takes for the surrounding vehicle RV to stop at a deceleration (e.g., 0.4G) due to a general brake operation. FIG. 9 shows a specified range (upper speed limit, lower speed limit) regarding the speed of the surrounding vehicle RV, and an upper time limit and a lower time limit regarding the time to collision (TTC). As described above in step S108, the specified range is the speed range of the surrounding vehicle RV in which driving assistance of the host vehicle SV is performed. The upper time limit is the upper limit of the time to collision arbitrarily set by the driver or the like, and the lower time limit is the lower limit of the time to collision set based on the measurement position accuracy of the GNSS.

[0047] The processing unit 21 sets the stop time corresponding to the speed of the surrounding vehicle RV as the time threshold based on the "relationship between the speed and the stop time of the surrounding vehicle RV" represented by the line 50 in FIG. 9. In the region 51 above the line 50, the arrival time is longer than the stop time, and if the driver of the surrounding vehicle RV performs a normal braking operation (e.g., deceleration of 0.4G), the surrounding vehicle RV can be stopped before it reaches the estimated intersection position CPe. Therefore, when the arrival time is longer than the time threshold (stop time), the driving assistance of the host vehicle SV may be suppressed. On the other hand, in the region 52 below the line 50, the arrival time is shorter than the stop time, and even if the driver of the surrounding vehicle RV performs a normal braking operation (e.g., deceleration of 0.4G), the surrounding vehicle RV can reach the estimated intersection position CPe before it stops. Therefore, when the arrival time is equal to or shorter than the time threshold (stop time), the driving assistance of the host vehicle SV may be executed. The processing unit 21 may change the time threshold continuously or stepwise according to the speed of the surrounding vehicle RV.

[0048] [Example 2] Hereinafter, a second embodiment of the method for predicting the collision possibility of the host vehicle SV will be described. In the second embodiment, an example of predicting the collision possibility of the host vehicle SV using the time to collision (TTC) will be described, as in the first embodiment. However, in the second embodiment, when at least one registered intersection position CP exists within the target area TA, the collision possibility is predicted using information related to the registered intersection position CP. In the method of the second embodiment, the collision possibility can be predicted by a simple (easy) process compared to the method of the first embodiment. FIG. 10 is a flowchart showing a method (second embodiment) for predicting the collision possibility of the host vehicle SV in step S106. The flowchart of FIG. 10 can be executed by the processing unit 21 (prediction unit 21b). Also, FIG. 11 is a diagram for explaining the method for predicting the collision possibility in the second embodiment. In the following, an example in which only one registered intersection position CP exists within the predetermined distance D will be described.

[0049] Here, the method of the second embodiment requires that at least one registered intersection position CP exists within the predetermined distance D, and that the target area TA is set to the second area TA2 via step S103. Furthermore, the method of the second embodiment requires that the surrounding vehicle RV exists (is located) on the travel path of the other vehicle OV used when registering the registered intersection position CP in the target area TA (second area TA2) in the intersection position database of the storage unit 22. The travel path of the other vehicle OV is stored in the storage unit 22 in association with the registered intersection position CP, and the processing unit 21 can determine whether or not the surrounding vehicle RV exists on the travel path of the other vehicle OV based on the travel path of the other vehicle OV and the surrounding vehicle information (the current position of the surrounding vehicle RV). If these conditions are not met, the processing unit 21 can predict the possibility of a collision using another prediction method such as the above-mentioned first embodiment.

[0050] In step S301, the processing unit 21 calculates a distance 43 between the nearby vehicle RV and the registered intersection position based on the nearby vehicle information acquired in step S105 and the registered intersection position CP in the target area TA (second area TA2). For example, the memory unit 22 stores a travel trajectory 32 of the other vehicle OV used when registering the registered intersection position CP in association with the registered intersection position CP. The processing unit 21 can calculate a distance 43 between the nearby vehicle RV and the registered intersection position CP on the travel trajectory 32 based on the travel trajectory 32 of the other vehicle OV stored in association with the registered intersection position CP.

[0051] In step S302, the processing unit 21 predicts, as a collision possibility, an arrival time required for the surrounding vehicle RV to reach the registered intersection position CP based on the distance 43 obtained in step S301 and the surrounding vehicle information acquired in step S105. For example, the processing unit 21 can predict the arrival time of the surrounding vehicle RV to the registered intersection position CP (hereinafter, may be simply referred to as "arrival time") by dividing the distance 43 by the speed of the surrounding vehicle RV included in the surrounding vehicle information.

[0052] In step S303, the processing unit 21 judges whether the arrival time obtained in step S302 is equal to or less than the time threshold. If the arrival time is equal to or less than the time threshold, the process proceeds to step S304, where the processing unit 21 judges that there is a possibility of a collision between the host vehicle SV and the surrounding vehicle RV, and then proceeds to step S107 in the flowchart of FIG. 6. On the other hand, if the arrival time is greater than the time threshold, the process proceeds to step S305, where the processing unit 21 judges that there is no possibility of a collision between the host vehicle SV and the surrounding vehicle RV, and then proceeds to step S107 in the flowchart of FIG. 6. Here, the time threshold can be set by an occupant of the host vehicle SV. Also, the processing unit 21 may change the time threshold according to the speed of the surrounding vehicle RV included in the surrounding vehicle information, as in the first embodiment.

[0053] [Example 3] Hereinafter, a third embodiment of the method for predicting the collision possibility of the host vehicle SV will be described. In the third embodiment, an example of predicting the collision possibility of the host vehicle SV using the stopping position of the surrounding vehicle RV will be described. FIG. 12 is a flowchart showing a method (third embodiment) for predicting the collision possibility of the host vehicle SV in step S106. The flowchart in FIG. 12 can be executed by the processing unit 21 (prediction unit 21b). Also, FIG. 13 is a diagram for explaining the method for predicting the collision possibility in the third embodiment.

[0054] In step S401, the processing unit 21 estimates a route (future driving route) that the host vehicle SV will travel in the future based on the host vehicle information acquired in step S105. Next, in step S402, the processing unit 21 estimates a route (future driving route) that the surrounding vehicle RV will travel in the future based on the surrounding vehicle information acquired in step S105. Note that steps S401 to S402 are similar to steps S201 to S202 in the flowchart of FIG. 7, and therefore detailed description thereof will be omitted here.

[0055] In step S403, the processing unit 21 determines whether the future travel path of the host vehicle SV estimated in step S401 intersects with the future travel path of the surrounding vehicle RV estimated in step S402. If it is determined that the future travel path of the host vehicle SV and the future travel path of the surrounding vehicle RV do not intersect, the process proceeds to step S409, and the processing unit 21 determines that there is no possibility of a collision between the host vehicle SV and the surrounding vehicle RV, and then proceeds to step S107 in the flowchart of FIG. 6. On the other hand, if it is determined that the future travel path of the host vehicle SV and the future travel path of the surrounding vehicle RV intersect, the process proceeds to step S404. Note that step S403 is the same process as step S203 in the flowchart of FIG. 7, and therefore a detailed description thereof will be omitted here.

[0056] In step S404, the processing unit 21 obtains an estimated intersection position CPe, which is a position where the future travel path of the host vehicle SV estimated in step S401 intersects with the future travel path of the surrounding vehicle RV estimated in step S402. Next, in step S405, the processing unit 21 determines whether the estimated intersection position CPe obtained in step S404 is within the target area TA. If it is determined that the estimated intersection position CPe is not within the target area TA, the processing unit 21 proceeds to step S409, and the processing unit 21 determines that there is no possibility of a collision between the host vehicle SV and the surrounding vehicle RV, and then proceeds to step S107 in the flowchart of FIG. 6. On the other hand, if it is determined that the estimated intersection position CPe is within the target area TA, the processing unit 21 proceeds to step S406. Note that steps S404 to S405 are similar to steps S204 to S205 in the flowchart of FIG. 7, and therefore detailed description thereof will be omitted here.

[0057] In step S406, the processing unit 21 predicts a stop position 44 when the surrounding vehicle RV decelerates from the current position at a predetermined deceleration as a collision possibility based on the surrounding vehicle information acquired in step S105. As the predetermined deceleration, a deceleration caused by a general brake operation (e.g., 0.4 G) may be used. For example, based on the current position and speed of the surrounding vehicle RV included in the surrounding vehicle information, the processing unit 21 calculates a distance from the current speed until the surrounding vehicle RV decelerates at a predetermined deceleration and stops, and adds the distance to the current position of the surrounding vehicle RV, thereby predicting a stop position 44 of the surrounding vehicle RV (hereinafter, may be simply referred to as "stop position 44") as shown in FIG. 13.

[0058] In step S407, the processing unit 21 judges whether the stop position 44 is ahead of the estimated intersection position CPe in the traveling direction of the surrounding vehicle RV. If the stop position 44 is ahead of the estimated intersection position CPe in the traveling direction of the surrounding vehicle RV, the process proceeds to step S408, and the processing unit 21 judges that there is a possibility of a collision between the host vehicle SV and the surrounding vehicle RV, and then proceeds to step S107 in the flowchart of FIG. 6. On the other hand, if the stop position 44 is not ahead of the estimated intersection position CPe in the traveling direction of the surrounding vehicle RV, that is, if the stop position 44 is behind (before) the estimated intersection position CPe in the traveling direction of the surrounding vehicle RV, the process proceeds to step S409, and the processing unit 21 judges that there is no possibility of a collision between the host vehicle SV and the surrounding vehicle RV, and then proceeds to step S107 in the flowchart of FIG. 6. Note that FIG. 13 shows an example in which the stop position 44 is behind the estimated intersection position CPe in the traveling direction of the surrounding vehicle RV.

[0059] <Register a new intersection location> Next, a method of registering a new intersection position in the intersection position database of the storage unit 22 will be described. The new intersection position is a position where the host vehicle SV and the surrounding vehicle RV intersect, and is identified by the identification unit 21d of the processing unit 21 and registered in the intersection position database of the storage unit 22 by the registration unit 21e. FIG. 14 is a flowchart showing a method of registering a new intersection position. The flowchart of FIG. 14 can be executed by the processing unit 21 in parallel with the flowchart of FIG. 6. Note that the flowchart of FIG. 14 can be repeatedly executed, for example, until the driving assistance setting is turned off or the ignition of the host vehicle SV is turned off.

[0060] In step S501, the processing unit 21 judges whether or not there is a surrounding vehicle RV. If it is judged that there is no surrounding vehicle RV, step S501 is repeated, and if it is judged that there is a surrounding vehicle RV, the processing unit 21 proceeds to step S502. Note that step S501 is the same process as step S104 in the flowchart of FIG. 6, and therefore a detailed description thereof will be omitted here. Also, this step S501 may be performed together with step S104 in the flowchart of FIG. 6. That is, this step S501 may use the judgment result in step S104 in the flowchart of FIG. 6.

[0061] In step S502, the processing unit 21 (acquisition unit 21a) acquires the host vehicle information and the surrounding vehicle information. Note that step S502 is the same process as step S105 in the flowchart of Fig. 6, and therefore a detailed description thereof will be omitted here. In addition, in this step S502, the host vehicle information and the surrounding vehicle information acquired in step S105 in the flowchart of Fig. 6 may be used.

[0062] In step S503, the processing unit 21 (identification unit 21d) determines whether or not the host vehicle SV and the peripheral vehicle RV have intersected based on the host vehicle information and the peripheral vehicle information acquired in step S502. The intersection of the host vehicle SV and the peripheral vehicle RV means that the host vehicle SV and the peripheral vehicle RV pass a common position with a difference in timing, and no collision has occurred between the host vehicle SV and the other vehicle OVer. For example, the processing unit 21 can determine whether or not the host vehicle SV and the peripheral vehicle RV have intersected based on the travel path of the host vehicle SV included in the host vehicle information and the travel path of the peripheral vehicle RV included in the peripheral vehicle information. If it is determined that the host vehicle SV and the peripheral vehicle RV have not yet intersected, the processing unit 21 proceeds to step S504, and if it is determined that the host vehicle SV and the peripheral vehicle RV have intersected, the processing unit 21 proceeds to step S505.

[0063] In step S504, the processing unit 21 (identification unit 21d) determines whether or not an intersection between the host vehicle SV and the surrounding vehicle RV will not occur in the future based on the host vehicle information and the surrounding vehicle information. For example, as shown in FIG. 15(a), when the host vehicle SV and the surrounding vehicle RV pass each other and then proceed in directions away from each other, the processing unit 21 can determine that an intersection between the host vehicle SV and the surrounding vehicle RV will not occur in the future. Also, as shown in FIG. 15(b), when the surrounding vehicle RV is traveling in a parking lot or the like and the host vehicle SV and the surrounding vehicle RV are proceeding in directions away from each other, the processing unit 21 can determine that an intersection between the host vehicle SV and the surrounding vehicle RV will not occur in the future. If it is determined that an intersection between the host vehicle SV and the surrounding vehicle RV will not occur in the future, the processing unit 21 proceeds to step S501, and if it is determined that an intersection between the host vehicle SV and the surrounding vehicle RV may occur in the future, the processing unit 21 proceeds to step S502.

[0064] In step S505, the processing unit 21 (identification unit 21d) identifies the position where the host vehicle SV and the surrounding vehicle RV intersect as a new intersection position CPn based on the host vehicle information and the surrounding vehicle information acquired in step S502. For example, the processing unit 21 can identify the position where the traveling trajectory of the host vehicle SV and the traveling trajectory of the surrounding vehicle RV intersect as a new intersection position CPn based on the traveling trajectory of the host vehicle SV included in the host vehicle information and the traveling trajectory of the surrounding vehicle RV included in the surrounding vehicle information.

[0065] In step S506, the processing unit 21 (registration unit 21e) registers the new intersection position CPn identified in step S505 in the intersection position database of the storage unit 22. If there is a limit to the number of registered intersection positions that can be registered in the intersection position database of the storage unit 22, the processing unit 21 deletes the oldest registered intersection positions from the intersection position database, and registers the new intersection position CPn in the intersection position database.

[0066] In step S507, the processing unit 21 (registration unit 21e) registers the travel trajectory of the surrounding vehicle RV up to the new intersection position CPn in the intersection position database of the storage unit 22 in association with the new intersection position CPn based on the surrounding vehicle information acquired so far. For example, as shown in FIG. 16, the travel trajectory of the surrounding vehicle RV is composed of a data string of a plurality of passing points 45 passed by the surrounding vehicle RV, that is, a data string of the current position included in the surrounding vehicle information acquired so far. The plurality of passing points 45 may be called a passing history (path history) regarding the surrounding vehicle RV. The processing unit 21 (registration unit 21e) registers the passing points among the plurality of passing points 45 that satisfy a predetermined condition as the travel trajectory of the surrounding vehicle RV in association with the new intersection position CPn in the intersection position database of the storage unit 22, and does not register (i.e., deletes) the other passing points. The specified conditions may include, for example, a first condition that the passing point 45 is within a specified distance from the new intersection position CPn, and a second condition that the difference between the orientation (passing orientation) of the surrounding vehicle RV when passing the passing point 45 and the orientation (passing orientation) of the surrounding vehicle RV when passing the new intersection position CPn is less than a threshold value.

[0067] In the example of FIG. 16, three of the multiple pass points 45a-45e are within the specified distance 46 from the new intersection position CPn, and therefore satisfy the first condition. In addition, when the pass direction of the surrounding vehicle RV at the new intersection position CPn is set as the reference direction 47, the difference between the pass direction 47 and the reference direction 47 of two of the pass directions 48a-48e of the surrounding vehicle RV at each of the pass points 45a-45e is less than the threshold. Therefore, the pass points 45d-45e corresponding to the pass directions 48d-48e respectively satisfy the second condition. In this case, the processing unit 21 (registration unit 21e) registers the pass points 45d-45e that satisfy the predetermined conditions (first condition, second condition) among the multiple pass points 45 in the intersection position database of the storage unit 22 in association with the new intersection position CPn, and deletes the other pass points 45a-45c. This makes it possible to reduce (reduce) the amount of data stored in the intersection position database of the storage unit 22. Note that the threshold value for the difference between the passing direction (reference direction) of the surrounding vehicle RV at the new intersection position CPn and the passing direction of the surrounding vehicle RV at each passing point can be set arbitrarily according to the amount of data in the storage unit 22. Also, although five passing points 45 are illustrated in Fig. 16, the number of passing points 45 is not limited to five and may be greater than five.

[0068] As described above, when none of the multiple registered intersection positions stored in the memory unit 22 is present within a predetermined distance ahead of the host vehicle SV, the driving assistance device 100 of this embodiment sets the target area TA to a first area TA1 and provides driving assistance for the host vehicle SV. On the other hand, when at least one registered intersection position CP among the multiple registered intersection positions stored in the memory unit 22 is present within a predetermined distance ahead of the host vehicle SV, the driving assistance device 100 sets the target area TA to a second area TA2 that is larger than the first area TA1 and provides driving assistance for the host vehicle SV. This allows appropriate driving assistance for the host vehicle to be provided.

[0069] <Summary of the embodiment> 1. The driving assistance device (e.g., 100) of the above embodiment is A storage means (e.g., 22) that stores a plurality of intersection positions (e.g., CPs) each indicating a position where a travel path of a host vehicle (e.g., SV) and a travel path of another vehicle (e.g., OV) have intersected in the past; An acquisition means (e.g., 21a) that acquires surrounding vehicle information including a current position, a speed, and a traveling trajectory of a surrounding vehicle (e.g., an RV) present around the host vehicle from the surrounding vehicle through vehicle-to-vehicle communication; a prediction means (e.g., 21b) for predicting a possibility of a collision between the host vehicle and the surrounding vehicle within a target area (e.g., TA) ahead of the host vehicle based on host vehicle information including a current position, speed, and travel trajectory of the host vehicle and the surrounding vehicle information acquired by the acquisition means; A support means (e.g., 21c) that provides driving support for the host vehicle, including at least one of notifying an occupant of the host vehicle and supporting deceleration of the host vehicle, based on the prediction result by the prediction means; Equipped with The prediction means includes: If none of the plurality of intersection positions stored in the storage means is present within a predetermined distance (e.g., D) ahead of the vehicle, the target area is set to a first area (e.g., TA1) to predict the possibility of collision; If at least one of the multiple intersection positions stored in the memory means is within the specified distance, the target area is set to a second area (e.g., TA2) larger than the first area, and the possibility of collision is predicted. According to this embodiment, when an intersection point where the driving path of the vehicle and the driving path of another vehicle have previously intersected is stored for a road including multiple lanes, the driving assistance for the vehicle can be appropriately performed by placing the intersection point within a target area for the driving assistance, thereby improving the safety of the vehicle.

[0070] 2. In the above embodiment, the storage means stores each of the plurality of intersection positions in association with a travel path of the other vehicle; When the at least one intersection position is present within the specified distance, the prediction means predicts the possibility of collision based on the driving trajectory of the other vehicle that is stored in the memory means in association with the at least one intersection position. According to this embodiment, it is possible to predict the possibility of a collision of the host vehicle with a simpler (easier) process based on the travel path of the other vehicle stored in the storage means.

[0071] 3. In the above embodiment, the prediction means determines a position where a future travel path of the surrounding vehicle estimated based on the surrounding vehicle information acquired by the acquisition means intersects with a future travel path of the host vehicle estimated based on the host vehicle information as an estimated intersection position (e.g., CPe), and predicts an arrival time for the surrounding vehicle to arrive at the estimated intersection position as the collision probability; The assistance means performs the driving assistance when the arrival time is equal to or less than a time threshold, and does not perform the driving assistance when the arrival time is greater than the time threshold. According to this embodiment, it is possible to accurately predict the possibility of a collision of the host vehicle with a surrounding vehicle, and to appropriately provide driving assistance for the host vehicle according to the collision possibility.

[0072] 4. In the above embodiment, the storage means stores each of the plurality of intersection positions in association with a travel path of the other vehicle; When the at least one intersection position is present within the predetermined distance, the prediction means calculates a distance (e.g., 43) between the at least one intersection position and the surrounding vehicle based on a travel trajectory of the other vehicle stored in the storage means in association with the at least one intersection position, and predicts an arrival time for the surrounding vehicle to arrive at the at least one intersection position as the collision possibility based on the distance and the surrounding vehicle information; The assistance means performs the driving assistance when the arrival time is equal to or less than a time threshold, and does not perform the driving assistance when the arrival time is greater than the time threshold. According to this embodiment, it is possible to accurately predict the possibility of collision of the host vehicle with a surrounding vehicle, and to appropriately perform driving assistance for the host vehicle according to the collision possibility. Also, it is possible to predict the possibility of collision of the host vehicle with a simpler (easier) process based on the travel trajectory of the other vehicle stored in the storage means.

[0073] 5. In the above embodiment, The assistance means changes the time threshold value depending on the speed of the nearby vehicle in the nearby vehicle information. According to this embodiment, it is possible to accurately predict the possibility of a collision of the host vehicle depending on the speed of surrounding vehicles.

[0074] 6. In the above embodiment, The time threshold is configurable by an occupant of the host vehicle. According to this embodiment, it is possible to accurately predict the collision possibility of the host vehicle in response to a request from an occupant of the host vehicle.

[0075] 7. In the above embodiment, The prediction means determines a position where a future travel path of the surrounding vehicle estimated based on the surrounding vehicle information acquired by the acquisition means intersects with a future travel path of the host vehicle estimated based on the host vehicle information as an estimated intersection position (e.g., CPe), and predicts a stopping position (e.g., 44) when the surrounding vehicle decelerates from a current position at a predetermined deceleration as the collision possibility, The assistance means provides the driving assistance when the stopping position is ahead of the estimated intersection position in the direction of travel of the surrounding vehicle, and does not provide the driving assistance when the stopping position is behind the estimated intersection position in the direction of travel of the surrounding vehicle. According to this embodiment, it is possible to accurately predict the possibility of a collision of the host vehicle with a surrounding vehicle, and to appropriately provide driving assistance for the host vehicle according to the collision possibility.

[0076] 8. In the above embodiment, The assistance means does not perform the driving assistance when the speed of the nearby vehicle in the nearby vehicle information is outside a specified range, regardless of the collision possibility predicted by the prediction means. According to this embodiment, driving assistance for the vehicle can be appropriately performed according to the speed of surrounding vehicles.

[0077] 9. In the above embodiment, A determination means (e.g., 21d) for determining a position where the host vehicle and the surrounding vehicle intersect as a new intersection position (e.g., CPn) based on the host vehicle information and the surrounding vehicle information; The vehicle further includes a registration means (eg, 21e) for registering the new intersection position identified by the identification means in the storage means. According to this embodiment, a newly identified intersection position can be stored in the storage means, and a plurality of intersection positions stored in the storage means can be appropriately updated.

[0078] 10. In the above embodiment, The traveling trajectory of the surrounding vehicle in the surrounding vehicle information is composed of a plurality of passing points (e.g., 45) through which the surrounding vehicle has passed, the registration means registers, in the storage means, a passing point among the plurality of passing points that satisfies a predetermined condition in association with the new intersection position; The specified conditions include a condition that the passing point is within a specified distance from the new intersection position, and a condition that the difference between the orientation of the surrounding vehicle when passing the passing point and the direction of the surrounding vehicle when passing the new intersection position is less than a threshold value. According to this embodiment, a passing point that satisfies a predetermined condition is selected from the acquired plurality of passing points and stored in the storage means, so that the amount of data stored in the storage means can be reduced.

[0079] 11. In the above embodiment, The second area is longer than the first area at least in the traveling direction of the host vehicle. According to this embodiment, the size of the target area can be changed so as to include the intersection position that exists ahead of the host vehicle, thereby improving the safety of the host vehicle.

[0080] The present invention is not limited to the above-described embodiments, and various modifications and variations are possible without departing from the spirit and scope of the present invention. [Explanation of symbols]

[0081] 11: sensor group, 12: GNSS antenna, 13: vehicle-to-vehicle communication antenna, 14: notification device, 15: braking device, 20: control device, 21: processing unit, 22: storage unit, 23: GNSS module, 23: vehicle-to-vehicle communication module, 100: driving assistance device

Claims

1. A storage means for storing a plurality of intersection positions each indicating a position where a travel path of the vehicle and a travel path of another vehicle have intersected in the past; an acquisition means for acquiring surrounding vehicle information including a current position, a speed, and a traveling trajectory of the surrounding vehicle from the surrounding vehicle through vehicle-to-vehicle communication; a prediction means for predicting a possibility of a collision between the host vehicle and the surrounding vehicle within a target area ahead of the host vehicle based on host vehicle information including a current position, a speed, and a traveling trajectory of the host vehicle and the surrounding vehicle information acquired by the acquisition means; a support means for providing driving support for the host vehicle, the driving support including at least one of a notification to an occupant of the host vehicle and a deceleration support for the host vehicle, based on a prediction result by the prediction means; Equipped with The prediction means includes: When none of the plurality of intersection positions stored in the storage means is present within a predetermined distance ahead of the host vehicle, the target area is set to a first area to predict the possibility of a collision; when at least one of the plurality of intersection positions stored in the storage means is present within the predetermined distance, the target area is set to a second area larger than the first area, and the possibility of collision is predicted; A driving assistance device comprising:

2. the storage means stores each of the plurality of intersection positions in association with a travel path of the other vehicle; 2. The driving assistance device according to claim 1, wherein the prediction means predicts the possibility of a collision based on a travel trajectory of the other vehicle that is stored in the storage means in association with the at least one intersection position when the at least one intersection position is present within the predetermined distance.

3. the prediction means determines a position where a future travel path of the surrounding vehicle estimated based on the surrounding vehicle information acquired by the acquisition means intersects with a future travel path of the host vehicle estimated based on the host vehicle information as an estimated intersection position, and predicts an arrival time for the surrounding vehicle to arrive at the estimated intersection position as the collision possibility; The driving assistance device according to claim 1 , wherein the assistance means performs the driving assistance when the arrival time is equal to or less than a time threshold, and does not perform the driving assistance when the arrival time is greater than the time threshold.

4. the storage means stores each of the plurality of intersection positions in association with a travel path of the other vehicle; the prediction means, when the at least one intersection position is present within the predetermined distance, calculates a distance between the at least one intersection position and the surrounding vehicle based on a travel trajectory of the other vehicle stored in the storage means in association with the at least one intersection position, and predicts, as the collision possibility, an arrival time required for the surrounding vehicle to arrive at the at least one intersection position based on the distance and the surrounding vehicle information; The driving assistance device according to claim 1 , wherein the assistance means performs the driving assistance when the arrival time is equal to or less than a time threshold, and does not perform the driving assistance when the arrival time is greater than the time threshold.

5. 5. The driving support device according to claim 3, wherein the support means changes the time threshold value in accordance with a speed of the nearby vehicle in the nearby vehicle information.

6. 5. The driving assistance device according to claim 3, wherein the time threshold value can be set by an occupant of the host vehicle.

7. the prediction means determines a position where a future travel path of the surrounding vehicle estimated based on the surrounding vehicle information acquired by the acquisition means intersects with a future travel path of the host vehicle estimated based on the host vehicle information as an estimated intersection position, and predicts, as the collision possibility, a stopping position of the surrounding vehicle when it decelerates from a current position at a predetermined deceleration; 2. The driving assistance device according to claim 1, wherein the assistance means performs the driving assistance when the stop position is ahead of the estimated intersection position in the traveling direction of the surrounding vehicles, and does not perform the driving assistance when the stop position is behind the estimated intersection position in the traveling direction of the surrounding vehicles.

8. 2. The driving assistance device according to claim 1, wherein the assistance means does not provide the driving assistance when the speed of the surrounding vehicle in the surrounding vehicle information is outside a specified range, regardless of the collision possibility predicted by the prediction means.

9. an identification means for identifying a position where the host vehicle and the surrounding vehicles intersect as a new intersection position based on the host vehicle information and the surrounding vehicle information; a registration means for registering the new intersection position identified by the identification means in a storage means; The driving assistance device according to claim 1 , further comprising:

10. the travel path of the surrounding vehicle in the surrounding vehicle information is configured by a plurality of passing points through which the surrounding vehicle has passed, the registration means registers, in the storage means, a passing point among the plurality of passing points that satisfies a predetermined condition in association with the new intersection position; 10. The driving assistance device according to claim 9, wherein the predetermined conditions include a condition that the passing point is within a specified distance from the new intersection position, and a condition that a difference between a direction of the surrounding vehicle when passing the passing point and a direction of the surrounding vehicle when passing the new intersection position is less than a threshold value.

11. The driving support device according to claim 1 , wherein the second area is longer than the first area at least in a traveling direction of the host vehicle.

12. a storage step of storing a plurality of intersection positions each indicating a position where a travel path of the host vehicle and a travel path of another vehicle have previously intersected; an acquisition step of acquiring surrounding vehicle information including a current position, a speed, and a traveling trajectory of the surrounding vehicle from the surrounding vehicle through vehicle-to-vehicle communication; a prediction step of predicting a possibility of a collision between the host vehicle and the surrounding vehicle within a target area ahead of the host vehicle based on host vehicle information including a current position, a speed, and a traveling trajectory of the host vehicle and the surrounding vehicle information acquired in the acquisition step; a support step of providing driving support for the host vehicle, the driving support step including at least one of notifying an occupant of the host vehicle and supporting deceleration of the host vehicle based on a result of the prediction step; Including, In the prediction step, When none of the plurality of intersection positions stored in the storing step is present within a predetermined distance ahead of the host vehicle, the target area is set to a first area to predict the possibility of a collision; When at least one of the plurality of intersection positions stored in the storing step is present within the predetermined distance, the target area is set to a second area larger than the first area, and the possibility of collision is predicted. A driving assistance method comprising:

13. A program for causing a computer to execute a driving assistance method, The driving assistance method includes: a storage step of storing a plurality of intersection positions each indicating a position where a travel path of the host vehicle and a travel path of another vehicle have previously intersected; an acquisition step of acquiring surrounding vehicle information including a current position, a speed, and a traveling trajectory of the surrounding vehicle from the surrounding vehicle through vehicle-to-vehicle communication; a prediction step of predicting a possibility of a collision between the host vehicle and the surrounding vehicle within a target area ahead of the host vehicle based on host vehicle information including a current position, a speed, and a traveling trajectory of the host vehicle and the surrounding vehicle information acquired in the acquisition step; a support step of providing driving support for the host vehicle, the driving support step including at least one of notifying an occupant of the host vehicle and supporting deceleration of the host vehicle based on a result of the prediction step; Including, In the prediction step, When none of the plurality of intersection positions stored in the storing step is present within a predetermined distance ahead of the host vehicle, the target area is set to a first area to predict the possibility of a collision; When at least one of the plurality of intersection positions stored in the storing step is present within the predetermined distance, the target area is set to a second area larger than the first area, and the possibility of collision is predicted. A program characterized by:

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