Control device for collision avoidance assistance, collision avoidance assistance method

Abstract

The present application relates to a control device for collision avoidance assistance, a collision avoidance assistance method. The control device for collision avoidance assistance includes a processor. The processor is configured to execute region setting processing that is processing of setting an assistance determination region that represents a specific region in front of a vehicle, execute accumulation processing that is processing of assigning a determination value determined in accordance with a position of an object to the object located in the assistance determination region and accumulating the determination value, and in a case where an accumulated value with respect to the object calculated by the accumulation processing exceeds a prescribed threshold value, perform collision avoidance assistance control of assisting in collision avoidance of the vehicle and the object based on driving environment information that represents a driving environment of the vehicle.

Description

TECHNICAL FIELD

[0001] The present application relates to a control device for assisting collision avoidance of a vehicle with an object and a collision avoidance assistance method. BACKGROUND

[0002] A travel assistance device that assists collision avoidance of a vehicle with an object in consideration of where the object is located on a road or a sidewalk is disclosed in Japanese Patent Application Publication No. 2018-012360.

[0003] The travel assistance device starts assistance in a case where it is predicted that the object will enter a region set in the surroundings of the vehicle within a prescribed time. Further, the travel assistance device determines whether the object is located in any one of a first road region (a region on a lane on which the host vehicle travels), a second road region (a region on a lane other than the first road region), and a sidewalk region. Also, the travel assistance device is configured to start assistance more easily in a case where the object is located in the first road region than in a case where the object is located in the second road region. Further, the travel assistance device is configured to start assistance more easily in a case where the object is located in the second road region than in a case where the object is located in the sidewalk region.

[0004] In order to predict whether the object will enter a certain region within a prescribed time, it is necessary to predict and give a moving speed of the object. The moving speed of the object in this case is given by predicting from a measured value obtained by a sensor, by being preset in the control device (for example, in a case where the object is a pedestrian, a standard walking speed of 5 kph is set), or the like.

[0005] However, the moving speed of the object differs depending on the respective states and environments of the object, and it is difficult to accurately predict and give the moving speed of the object.

[0006] Therefore, if control for assisting collision avoidance (collision avoidance assistance control) is executed with the condition that the object enters a certain range, the collision avoidance assistance control can be executed in a case where assistance for collision avoidance is not needed. Further, the passengers / occupants of the vehicle can be inconvenienced. SUMMARY

[0007] The present application provides a control device for collision avoidance assistance and a collision avoidance assistance method for a vehicle configured to suppress unnecessary operation of collision avoidance assistance control.

[0008] A first aspect of the present disclosure is a control device. The control device includes a processor configured to perform collision avoidance assistance control. The processor is configured to perform region setting processing that sets an assistance determination region representing a specific region in front of a vehicle, perform accumulation processing that assigns a determination value determined in accordance with a position of an object located in the assistance determination region to the object and performs accumulation, and perform collision avoidance assistance control that assists in collision avoidance of the vehicle and the object based on driving environment information representing a driving environment of the vehicle in a case where an accumulated value calculated by the accumulation processing exceeds a prescribed threshold value.

[0009] In the first aspect, the processor can also be configured to, in the region setting processing, set a plurality of assumed lateral velocities that are assumed values of a speed of the object in a direction perpendicular to a traveling direction of the vehicle, and can also set an attention region that is a region in which the object will be located in a passing region of the vehicle with a collision surplus time of a prescribed value or less for each of the set assumed lateral velocities. The assistance determination region can also be given by merging of the respective attention regions. In the accumulation processing, the determination value can be a value determined for each region divided by a boundary line of the respective attention regions.

[0010] In the first aspect, the processor can also be configured to acquire information of a category of the object, and set the assumed lateral velocity based on the category of the object in the region setting processing.

[0011] A second aspect of the present disclosure is a collision avoidance assistance method. The collision avoidance assistance method is a method of assisting in collision avoidance of a vehicle and an object, including region setting processing that sets an assistance determination region representing a specific region in front of the vehicle, accumulation processing that assigns a determination value determined in accordance with a position of the object located in the assistance determination region to the object and performs accumulation, and performing assistance in collision avoidance of the object in a case where an accumulated value of the object calculated in the accumulation processing exceeds a prescribed threshold value.

[0012] In the second aspect, the region setting processing can include setting a plurality of assumed lateral velocities that are assumed values of a speed of the object in a direction perpendicular to a traveling direction of the vehicle, and setting an attention region that is a region in which the object will be located in a passing region of the vehicle with a collision surplus time of a prescribed value or less for each of the set assumed lateral velocities. The assistance determination region can also be a region of merging of the respective attention regions. In the accumulation processing, the determination value can be a value determined for each region divided by a boundary line of the respective attention regions.

[0013] In the second aspect, the assumed lateral velocity can also be set based on a category of the object in the region setting processing.

[0014] According to the first and second aspects of the present disclosure, an object located within an auxiliary determination region is taken as a target of collision avoidance assistance, a determination value is given according to the position of the object and is accumulated, and in the case where the accumulated value exceeds a prescribed threshold value, assistance in collision avoidance for the object is performed. Thus, in the case where the moving speed of the object is greater or less than the predicted speed and assistance in collision avoidance is not needed, collision avoidance assistance control can be inhibited from operating. Furthermore, the annoyance of the passengers / occupants of the vehicle can be reduced. BRIEF DESCRIPTION OF DRAWINGS

[0015] Features, advantages, and technical and industrial significance of exemplary embodiments of the present application will be described below with reference to the accompanying drawings, wherein the same reference numerals are denoted throughout the same elements, and wherein:

[0016] Figure 1A is a conceptual diagram for explaining collision avoidance assistance control.

[0017] Figure 1B is a conceptual diagram for explaining collision avoidance assistance control in the case where assistance in collision avoidance is performed by brake control.

[0018] Figure 1C is a conceptual diagram for explaining collision avoidance assistance control in the case where assistance in collision avoidance is performed by steering control.

[0019] Figure 2 is a conceptual diagram showing an example of a notice region set based on the longitudinal velocity and lateral velocity of an object that is a target of collision avoidance.

[0020] Figure 3A is a conceptual diagram for explaining a notice region that varies according to the longitudinal velocity and lateral velocity of an object that is a target of collision avoidance.

[0021] Figure 3B is a conceptual diagram for explaining a notice region that varies according to the longitudinal velocity and lateral velocity of an object that is a target of collision avoidance.

[0022] Figure 3C is a conceptual diagram for explaining a notice region that varies according to the longitudinal velocity and lateral velocity of an object that is a target of collision avoidance.

[0023] Figure 3D is a conceptual diagram for explaining a notice region that varies according to the longitudinal velocity and lateral velocity of an object that is a target of collision avoidance.

[0024] Figure 4is a conceptual diagram for explaining unnecessary work of collision avoidance assist control accompanying a difference between a speed of an object given at the time of setting a notice region and an actual speed of the object.

[0025] Figure 5 is a conceptual diagram showing an example of an assist determination region set by the control device of the embodiment.

[0026] Figure 6 is a block diagram showing a configuration of a vehicle system of a vehicle equipped with the control device of the embodiment.

[0027] Figure 7 is a flowchart showing a process performed by the processor according to the collision avoidance assist control program.

[0028] Figure 8 is a conceptual diagram showing an example of an assist determination region set in the region setting process shown in the flowchart of Figure 7

[0029] Figure 9 is a conceptual diagram for explaining the position determination of the object shown in the flowchart of Figure 7

[0030] Figure 10 is a conceptual diagram showing an example of a determination value given according to the position of the object within the assist determination region in the accumulation process shown in the flowchart of Figure 7

[0031] Figure 11 is a conceptual diagram for explaining the effect of the control device of the embodiment.

[0032] Figure 12 is a graph showing the cumulative value in each of the movement paths shown in Figure 11 DETAILED DESCRIPTION

[0033] Hereinafter, an embodiment of the present application will be described with reference to the accompanying drawings. In the embodiment shown below, in the case where a numerical value of the number, the quantity, the amount, the range, and the like of each element is mentioned, the present application is not limited to the mentioned numerical value except for the case where it is particularly mentioned or it is obviously determined as the numerical value in principle. Further, in the case where a configuration and the like described in the embodiment shown below is mentioned, it is not necessarily required in the present application except for the case where it is particularly mentioned or it is obviously determined as the configuration in principle. Note that, in each drawing, the same reference numerals are attached to the same or equivalent portions, and the repeated description is appropriately simplified or omitted.

[0034] 1. SUMMARY

[0035] ​​​​The control device of the embodiment performs collision avoidance assistance control that assists in collision avoidance of the vehicle and an object. As the object that becomes the target of collision avoidance, a pedestrian, a bicycle, a parked vehicle, an obstacle, and the like are exemplified. Typically, the control device of the embodiment is an ECU (Electronic Control Unit) mounted on the vehicle. However, the control device can also be a device external to the vehicle that remotely performs control of the vehicle. Furthermore, the form of the vehicle on which the control device of the embodiment is mounted is not particularly limited.

[0036] Figure 1A is a conceptual diagram for describing collision avoidance assistance control. Figure 1B is a conceptual diagram for describing collision avoidance assistance control in a case where assistance in collision avoidance is performed by brake control. Figure 1C is a conceptual diagram for describing collision avoidance assistance control in a case where assistance in collision avoidance is performed by steering control. Figure 1A Figure 1B and Figure 1C shows a case where the vehicle 1 is traveling on a roadway and performs collision avoidance assistance control with a stationary object ST on the roadway as the target. The collision avoidance assistance control is performed by the control device 100 mounted on the vehicle 1.

[0037] The collision avoidance assistance control is performed in a case where the control device 100 determines that collision avoidance with the object is not easy if the current traveling state (speed, direction of travel, and the like) of the vehicle 1 is maintained. As the collision avoidance assistance control, it is typical to perform assistance in collision avoidance by controlling the brake or the steering of the vehicle 1. Figure 1B shows a case where assistance in collision avoidance achieved by brake control is performed, Figure 1C shows a case where assistance in collision avoidance achieved by steering control is performed.

[0038] As shown in Figure 1B , the vehicle 1 is decelerated by brake control, whereby collision avoidance can be performed with ease. Furthermore, as shown in Figure 1C , the steering of the vehicle 1 is performed by steering control, whereby collision avoidance can also be performed with ease.

[0039] In the determination of whether or not to perform collision avoidance assistance control, the Time To Collision (TTC) with the object has been used in the past. The TTC indicates the time until the vehicle 1 collides with the object in a case where the current relative speed (hereinafter, also simply referred to as "relative speed") of the vehicle 1 and the object in the direction of travel of the vehicle 1 is maintained. Therefore, in a case where the TTC becomes a prescribed value or less, it can be determined that collision avoidance is not easy.​

[0040] Further, in the determination of whether to perform the collision avoidance assist control, the position (hereinafter, also referred to as "lateral position") and the speed (hereinafter, also referred to as "lateral speed") of the object in a direction perpendicular to the traveling direction of the vehicle 1 (hereinafter, also referred to as "perpendicular direction") should also be considered. This is because, depending on the lateral position and the lateral speed of the object, it is considered that the object will not be located in the passing area of the vehicle 1 with a TTC below a prescribed value, so that the assist of collision avoidance is not needed. For example, a case where the lateral position of the object is sufficiently far from the vehicle 1 and is moving in the traveling direction or is moving in a direction away from the vehicle 1, a case where the lateral speed of the object is sufficiently large and the object is out of the passing area of the vehicle 1 so that the TTC will not become below the prescribed value, and the like.

[0041] Therefore, conventionally, it has been considered that, based on the speed in the traveling direction (hereinafter, also referred to as "longitudinal speed") and the lateral speed of the object, an attention area indicating a specific area is set in front of the vehicle 1, and the collision avoidance assist control is performed with the condition that the object is located in the attention area.

[0042] Figure 2 is a conceptual diagram indicating an example of an attention area set based on the longitudinal speed and the lateral speed of the object CT. Figure 2 A case where the vehicle 1 is traveling at a speed V and the determination of whether to perform the collision avoidance assist control with respect to the object CT is being performed is shown. Here, the object CT is located on the left side as viewed from the vehicle 1 and is moving in a direction approaching the vehicle 1 at a longitudinal speed TVd, and is moving in a direction to the right side as viewed from the vehicle 1 at a lateral speed TVp.

[0043] In Figure 2 , the distances indicated by TTC≤t1 and TTC≤t2 are distances advanced with the relative speed V - TVd between the time t1 and the time t2. Further, the sizes of the inclinations of the first boundary line and the second boundary line as the boundary lines of the attention area are the same as each other, and are indicated by the ratio of the relative speed V - TVd to the lateral speed TVp of the object CT (the direction in which the object CT approaches as viewed from the vehicle 1).

[0044] That is, Figure 2 The attention area shown in Figure 2 can be set by giving the relative speed V - TVd and the lateral speed TVp.

[0045] Note that, for a case where the object CT is located on the right side as viewed from the vehicle 1, the attention area can also be set similarly. At this time, the attention area is the same as Figure 2The illustrated attention region becomes a shape that is inclined to the right side as viewed from the vehicle 1 symmetrically. Further, in a case where the object CT moves in a direction away from the vehicle 1, such an attention region is not set. For example, a case where the object CT is located on the left side as viewed from the vehicle 1 and moves in the vertical direction on the left side as viewed from the vehicle 1, and a case where the object CT is located on the right side as viewed from the vehicle 1 and moves in the vertical direction on the right side as viewed from the vehicle 1.

[0046] In addition to this, in order to suppress the collision avoidance assist control from working for the object CT outside the lane region, it is possible to consider restricting the attention region to the lane region. In this case, it is determined whether the object CT is located in the lane region. Also, it is sometimes determined whether the object CT is about to cross the lane region.

[0047] Such an attention region varies depending on the speed of the object CT that becomes the target. Figure 3A 、 Figure 3B 、 Figure 3C 、 Figure 3D is a conceptual diagram for describing the attention region that varies depending on the speed of the object CT. Figure 3A 、 Figure 3B 、 Figure 3C 、 Figure 3D The same situation as Figure 2 is shown, Figure 3A 、 Figure 3B 、 Figure 3C 、 Figure 3D respectively show cases where the longitudinal speed and the lateral speed of the object CT are different. Here, Figure 3A The illustrated attention region is equivalent to the attention region illustrated in Figure 2 .

[0048] In Figure 3B , the object CT moves in the longitudinal direction at the longitudinal speed TVd in a direction approaching the vehicle 1 and moves in the lateral direction at the lateral speed TVp2 in a direction on the right side as viewed from the vehicle 1. Here, the magnitude of the lateral speed TVp2 is larger than the lateral speed TVp of the object CT illustrated in Figure 3A . Therefore, the attention region becomes a shape that is inclined more to the left side as viewed from the vehicle 1 than in Figure 3A .

[0049] In Figure 3C , the object CT moves in the longitudinal direction at the longitudinal speed TVd in a direction away from the vehicle 1 and moves in the lateral direction at the lateral speed TVp in a direction on the right side as viewed from the vehicle 1. The relative speed V - TVd becomes smaller compared to Figure 3A , and therefore the attention region becomes a shape that is shortened in the advancing direction.

[0050] In Figure 3DIn this case, it is shown that the object CT moves in the longitudinal direction at a longitudinal speed TVd without having a lateral speed in the direction of approaching the vehicle 1. At this time, the attention region becomes a rectangular region that is a part of the passing region.

[0051] Here, in terms of the magnitude of the lateral speed TVp of the object CT given at the time of setting the attention region, there are a case where it is predicted and given in accordance with the detection value of the sensor and a case where it is given in advance in accordance with the category of the object CT. In the case where it is given in advance in accordance with the category of the object CT, the magnitude of the lateral speed TVp of the object CT is given, for example, by a general walking speed of 5 kph when the object CT is detected as a pedestrian.

[0052] However, the speed of the object CT differs in accordance with the respective states, environments, and it is difficult to accurately predict and give the speed for a certain period of time at the time of setting the attention region. When there is a difference between the predicted speed of the object CT and the actual speed of the object CT, it can cause unnecessary operation of the collision avoidance assist control.

[0053] Figure 4 is a conceptual diagram for describing unnecessary operation of the collision avoidance assist control that accompanies a difference between the predicted speed of the object CT and the actual speed of the object CT. In Figure 4 In the case where the actual lateral speed of the object CT is smaller than the predicted speed of the object CT (path 2), the case where the lateral speed is larger than the predicted speed of the object CT (path 3), and the like, the object CT does not actually come to the passing region of the vehicle 1 at the TTC of the prescribed value tl or less in some cases. In such a case, the assist for the collision avoidance of the object CT is not needed.

[0054] Therefore, the control device 100 of the present embodiment sets an assist determination region that indicates a specific region in front of the vehicle 1, and accumulates a determination value that is determined in accordance with the position within the assist determination region of the object CT for each control cycle. Then, in the case where the accumulated value exceeds a prescribed threshold value, the collision avoidance assist control is performed. Here, the assist determination region is a region in which a plurality of assumed values of the lateral speed of the object CT (hereinafter, also referred to as "assumed lateral speed") are set, and the merging of the attention regions that are set for each of the set assumed lateral speeds.

[0055] Figure 5 is a conceptual diagram that shows an example of the assist determination region set in the control device 100 of the present embodiment. In Figure 5In this embodiment, 3 kph, 5 kph, and 8 kph are set as the assumed lateral velocities of the object CT. The auxiliary determination region (region surrounded by the thick line) becomes a combination of the attention regions set for each of the assumed lateral velocities set. Further, the determination value is given for each region divided by the boundary line. In this embodiment, the determination value of 0.2 is given to the object CT. The control device 100 of this embodiment accumulates the determination value thus given for each control cycle, and performs the collision avoidance auxiliary control in the case where the threshold value (for example, exceeds 1) is exceeded. Figure 5

[0056] Thus, the judgment of whether to perform the collision avoidance auxiliary control is performed, whereby the collision avoidance auxiliary control is not immediately performed with the condition that the object CT is located in the attention region, and thus it is possible to suppress unnecessary work of the collision avoidance auxiliary control. Further, it is possible to reduce the trouble of the passenger / occupant of the vehicle 1.

[0057] 2. Configuration

[0058] Figure 6 is a block diagram showing the configuration of the vehicle system 10 of the vehicle 1 provided with the control device 100 of this embodiment. The vehicle system 10 includes the control device 100, the sensor system 200, the communication device 210, and the actuator system 300. The control device 100 is connected to the sensor system 200, the communication device 210, and the actuator system 300 by electricity or wirelessly, and is configured to be able to transmit and receive information to and from each other.

[0059] The sensor system 200 is a system of sensors that detects and outputs information indicating the driving environment of the vehicle 1 (driving environment information). The sensor system 200 includes a running state detection sensor 201 and a surrounding environment detection sensor 202.

[0060] The running state detection sensor 201 detects and outputs the running state (vehicle speed, acceleration, yaw rate, etc.) of the vehicle 1. The running state detection sensor 201 is, for example, a wheel speed sensor, a G sensor, a gyro sensor, or the like.

[0061] The surrounding environment detection sensor 202 detects information on the environment (lane, obstacle, preceding vehicle, etc.) around the vehicle. The surrounding environment detection sensor 202 is, for example, a millimeter wave radar, a camera, a LiDAR (Light Detection And Ranging), or the like.

[0062] Note that the sensor system 200 can also include a sensor that detects other driving environment information.

[0063] ​The communication device 210 performs transmission and reception of various kinds of information (communication information) by communicating with devices outside the vehicle. The communication device 210 is, for example, a device for performing inter-vehicle communication, road-to-vehicle communication, a device that provides a GPS (Global Positioning System) function, a device that performs transmission and reception of communication information with a server connected to a communication network and disposed on the network, and the like. The communication information acquired by the control device 100 via the communication device 210 is, for example, map information, road traffic information, and the like. The communication of the communication device 210 can be performed in an arbitrary manner. For example, the communication can be performed by transmission and reception of electric waves, or can be transmission and reception of information via a network.

[0064] The control device 100 performs various kinds of processing of control of the vehicle 1 based on the acquired information, generates a control signal. Then, the control signal is output to the actuator system 300 described later. Typically, the control device 100 is an ECU mounted on the vehicle. However, the control device 100 can also be a device outside the vehicle 1. In this case, the control device 100 performs acquisition of information and output of a control signal to the actuator system 300 via communication with the vehicle 1.

[0065] The control device 100 is provided with a memory 110 and a processor 120. The memory 110 includes a RAM (Random Access Memory) that temporarily stores data, and a ROM (Read Only Memory) that stores a program executable by the processor, and various kinds of data of the program. The information acquired by the control device 100 is stored in the memory 110. The processor 120 reads out the program from the memory 110, and performs processing according to the program based on various kinds of data read out from the memory 110.

[0066] The program stored in the memory 110 includes at least a program of collision avoidance assistance control (collision avoidance assistance control program 111). The processor 120 generates a control signal of collision avoidance assistance control of the vehicle 1 by performing processing according to the collision avoidance assistance control program 111. Details of the processing performed by the processor 120 according to the collision avoidance assistance control program 111 will be described later.

[0067] Note that, in a case where the control device 100 performs other processing of control of the vehicle 1, each processing can be given as a part of one program, or each processing can be given by a different program and executed by a different processor. Alternatively, each processing can be executed by a different ECU. In this case, the control device 100 is constituted by a plurality of ECUs. At this time, each ECU is configured to transmit information to each other to the extent that information required for execution of processing can be acquired.

[0068] The actuator system 300 is a system of actuators that act in accordance with the control signals given by the control device 100. The actuators included in the actuator system 300 are, for example, actuators that drive the engine (internal combustion engine, electric motor, or a hybrid thereof, etc.), actuators that drive the brake mechanism possessed by the vehicle 1, actuators that drive the steering mechanism of the vehicle 1, and the like. The various actuators included in the actuator system 300 act in accordance with the control signals, whereby various controls of the vehicle 1 are implemented.

[0069] 3. Process

[0070] Next, the process executed by the processor 120 in accordance with the collision avoidance assistance control program 111 will be described. Figure 7 is a flowchart showing the process executed by the processor 120 in accordance with the collision avoidance assistance control program 111. Figure 7 The process shown in FIG. 10 starts when the surrounding environment detection sensor 202 senses an object CT (pedestrian, bicycle, stopped vehicle, obstacle, etc.) that can be the target of collision avoidance in front of the vehicle 1 and the control device 100 acquires the detection information of the object CT.

[0071] In step S100, the processor 120 calculates the information of the object CT on the basis of the acquired information. The calculated information of the object CT includes at least the relative speed and TTC of the vehicle 1 with respect to the object CT, the lateral position of the object CT, and the category of the object CT.

[0072] The relative speed and TTC of the vehicle 1 with respect to the object CT can be calculated, for example, from the speed of the vehicle 1, the distance between the vehicle 1 and the object CT, and the longitudinal speed of the object CT. The lateral position of the object CT can be calculated, for example, from the distance between the vehicle 1 and the object CT. Typically, the category of the object CT is included in the information detected by the surrounding environment detection sensor 202. The relative speed and TTC of the vehicle 1 with respect to the object CT and the lateral position of the object CT can also be included in the information detected by the surrounding environment detection sensor 202.

[0073] After step S100, the process proceeds to step S110.

[0074] In step S110 (region setting process), the processor 120 sets an assistance determination region that represents a specific region in front of the vehicle 1. The setting of the assistance determination region is performed as follows.

[0075] First, a plurality of assumed lateral velocities are set based on the category of the object CT. For example, in step S100, in a case where it is assumed that the category of the object CT is a pedestrian, five assumed lateral velocities of 1 kph, 3 kph, 5 kph, 8 kph, and 10 kph are set. In a case where it is assumed that the category of the object CT is a bicycle, five assumed lateral velocities of 10 kph, 12 kph, 15 kph, 18 kph, and 20 kph are set. The assumed lateral velocities thus set in accordance with the category of the object CT are values given in advance in the collision avoidance assistance control program 111, or values determined by a prescribed algorithm in accordance with the detected current lateral velocity of the object CT. These values or algorithm can be optimally given by experiment by performing vehicle adaptation of the vehicle 1 provided with the vehicle system 10 of the present embodiment, or the like. Hereinafter, it is assumed that the category of the object CT is a pedestrian, and five assumed lateral velocities of 1 kph, 3 kph, 5 kph, 8 kph, and 10 kph are set.

[0076] Next, for each of the assumed lateral velocities set, an attention region is set based on the relative velocity calculated in step S100, and the combination of the respective attention regions set is set as an assistance determination region. The respective attention regions set here are equivalent to the contents described in Figure 2 in the foregoing. In this case, the magnitude of the inclination of the first boundary line and the second boundary line of the attention region differs for each of the assumed lateral velocities set. Further, the prescribed values t1 and t2 are values given in advance in the collision avoidance assistance control program 111, and are optimally given by experiment. The TTC is a time based on the value calculated in step S100.

[0077] Figure 8 An example of the assistance determination region set in step S110 is shown in Figure 8 In Figure 8 , the first boundary line of the attention region set for the assumed lateral velocity of 1 kph and the second boundary line of the attention region set for the assumed lateral velocity of 10 kph are omitted. As

[0078] Referring back to Figure 7 , after step S110, the process proceeds to step S120.

[0079] In step S120, the processor 120 determines which position the object CT is in in relation to the assistance determination region. The determination of the position of the object CT is made based on the TTC and the lateral position calculated in step S100. Figure 9 is a conceptual diagram for explaining the determination of the position of the object CT.Figure 9 the longitudinal axis indicates the position of the traveling direction corresponding to the value of TTC. Figure 9 the transverse axis indicates the transverse position.

[0080] For the object CT, assume that TTC is s (t1≤s≤t2) and the transverse position is x. At this time, as shown in Figure 9 , the position of the object CT is determined. However, the determination of the position of the object CT can also be made based on other values. For example, it can also be determined based on the distance between the vehicle 1 and the object CT detected by the surrounding environment detection sensor 202.

[0081] Referring again to Figure 7 , after step S120, the processing proceeds to step S130.

[0082] In step S130, the processor 120 determines whether the object CT is the target of collision avoidance. Here, in the case where the object CT is located within the auxiliary determination region, the object CT is determined to be the target of collision avoidance. In the case where the object CT is located within the auxiliary determination region (step S130: YES), the processing proceeds to step S140. In the case where the object CT is not located within the auxiliary determination region (step S130: NO), the processing ends.

[0083] Note that even in the case where the object CT is not the target of collision avoidance and the processing ends, in the case where the control device 100 acquires detection information of the same object CT from the surrounding environment detection sensor 202, the processing shown in Figure 7 is started again with respect to the same object CT.

[0084] In step S140 (accumulation processing), the processor 120 gives the determination value determined according to the position to the object CT that is the target of collision avoidance and accumulates it, and calculates the accumulated value. The accumulated value is stored until the processing of the object CT as the target ends. Figure 10 Examples of the determination value given according to the position of the object CT are shown in Figure 10 . As shown in , the determination value is determined for each region divided by the boundary lines of the respective set attention regions. Here, "reset" indicates that the accumulated value is set to 0.

[0085] Figure 10 In , as a comparison, three objects CT1, CT2, and CT3 are shown. The object CT1 is located in the region of the determination value 0.4, and thus the determination value 0.4 is accumulated in the accumulated value for the object CT1. The object CT2 is located in the region of the determination value 0, and thus the accumulated value for the object CT2 is not changed. The object CT3 is located in the region of the reset of the determination value, and thus the accumulated value for the object CT3 becomes 0.

[0086] Referring again to Figure 7 After the step S140, the process proceeds to a step S150.

[0087] In the step S150, the processor 120 determines whether or not the cumulative value calculated in the step S140 becomes a prescribed threshold value k or more. The threshold value k is a value given in advance in the collision avoidance assist control program 111, and is optimally given through experiments. In a case where the cumulative value becomes the threshold value k or more (step S150: YES), the process proceeds to a step S160. In a case where the cumulative value is smaller than the threshold value k (step S150: NO), the process returns to the step S100 and is repeatedly executed.

[0088] In the step S160, the processor 120 performs collision avoidance assist control. The object as a target of the collision avoidance assist control is the object CT determined to have the cumulative value of the threshold value k or more. Note that the method of the collision avoidance assist control is not particularly limited. It can be either brake control of the vehicle 1 or steering control of the vehicle 1. Alternatively, it can be control of the vehicle 1 performed by combining the brake control and the steering control based on the driving environment information.

[0089] After the step S160, the process ends.

[0090] 4. Effects

[0091] As explained above, according to the control device 100 of the present embodiment, an assist determination region representing a specific region is set in front of the vehicle 1, and a determination value determined in accordance with a position within the assist determination region of the object CT is accumulated per control cycle. Then, in a case where the cumulative value becomes a prescribed threshold value k or more, collision avoidance assist control is performed. Thereby, unnecessary operation of the collision avoidance assist control can be suppressed.

[0092] Figure 11 and Figure 12 are conceptual diagrams and graphs for explaining the effects of the control device 100 of the present embodiment. In Figure 11 , the assist determination region and the determination value are equivalent to those shown in Figure 8 and Figure 10 . That is, assuming that the category of the object CT is a pedestrian, five, 1 kph, 3 kph, 5 kph, 8 kph, and 10 kph, are set as the assumed lateral velocities. Figure 11 In Figure 12 , three, path 1, path 2, and path 3, are shown as the movement paths of the object CT. On each of the movement paths, the position of t = 0 is set as a starting point (a position at which the object CT is sensed), and the position of the object CT per control cycle of the control device 100 is shown. Figure 11 andCorrespondingly, the cumulative value on each movement path is shown. Here, the control period of the control device 100 is set to dt. Further, the value of the threshold value k is set to 1.

[0093] Path 1 shows an example of a case where the lateral velocity of the object CT is a general walking speed of 5 kph. In this case, as shown in Figure 12 at time 3dt, the cumulative value becomes the threshold value k or more, so collision avoidance assist control is performed.

[0094] Path 2 shows an example of a case where the lateral velocity of the object CT is small, the TTC is the prescribed value or less, and the object CT is not located in the passing region of the vehicle 1. In this case, as shown in Figure 12 the cumulative value does not become the threshold value k or more, so collision avoidance assist control is not performed.

[0095] Path 3 shows an example of a case where the lateral velocity of the object CT is large, and the object CT rapidly passes through the passing region of the vehicle 1. In this case, as shown in Figure 12 the cumulative value does not become the threshold value k or more, so collision avoidance assist control is not performed. Further, in the example shown in Figure 12 at time 2dt, the object CT is located outside the assist determination region, so the object CT becomes outside the target of collision avoidance.

[0096] Thus, it is possible to suppress collision avoidance assist control from operating in a case where the velocity of the object CT is large or small with respect to the predicted velocity, and the assist is not needed for collision avoidance. Further, it is possible to reduce the annoyance of the passenger / occupant of the vehicle 1.

[0097] Further, by appropriately determining the prescribed values tl and t2, the determination value, the threshold value k, and the like, it is possible to suppress collision avoidance assist control from operating with respect to the object CT outside the road region, so it is also possible to not limit collision avoidance assist control to the road region. Further, it is possible to suppress unnecessary operation of collision avoidance assist control due to misrecognition of the object CT (determination of whether or not located in the road region, determination of whether or not desiring to cross the road region, and the like).

Claims

1. A control device for collision avoidance assist, characterized by, including a processor, the processor is configured to: execute region setting processing that sets an auxiliary determination region that represents a specific region in front of a vehicle; execute accumulation processing that assigns a determination value determined in accordance with a position of an object located in the auxiliary determination region to the object and accumulates the determination value; and in a case where an accumulated value for the object calculated through the accumulation processing exceeds a prescribed threshold value, perform collision avoidance assistance control that assists in collision avoidance of the vehicle and the object based on driving environment information that represents a driving environment of the vehicle, the processor is configured to, in the region setting processing, set a plurality of assumed lateral velocities that are assumed values of a velocity of the object in a direction perpendicular to a traveling direction of the vehicle; and set, for each of the set assumed lateral velocities, an attention region that is a region in which the object will be located in a passing region of the vehicle with a collision surplus time of a prescribed value or less, the auxiliary determination region is a region in which each of the attention regions is merged, and, in the accumulation processing, the determination value is a value determined for each region divided by a boundary line of each of the attention regions.

2. The control device according to claim 1, wherein the processor is configured to: obtain information of a category of the object; and in the region setting processing, set the assumed lateral velocities based on the category of the object.

3. A collision avoidance assistance method characterized by, including: region setting processing that sets an auxiliary determination region that represents a specific region in front of a vehicle; accumulation processing that assigns a determination value determined in accordance with a position of an object located in the auxiliary determination region to the object and accumulates the determination value; and in a case where an accumulated value for the object calculated through the accumulation processing exceeds a prescribed threshold value, perform assistance in collision avoidance of the object, the region setting processing includes: setting a plurality of assumed lateral velocities that are assumed values of a velocity of the object in a direction perpendicular to a traveling direction of the vehicle; and setting, for each of the set assumed lateral velocities, an attention region that is a region in which the object will be located in a passing region of the vehicle with a collision surplus time of a prescribed value or less, the auxiliary determination region is a region in which each of the attention regions is merged, the determination value is a value determined for each region divided by a boundary line of each of the attention regions.

4. The collision avoidance assistance method according to claim 3, wherein in the region setting processing, the assumed lateral velocities are set based on a category of the object.

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