Anti-collision device

Abstract

A collision avoidance device includes a driving support ECU configured to determine a possibility of a collision between a vehicle and an obstacle when it is determined that the obstacle is present in front of the vehicle based on information acquired by an object information acquisition device that acquires information of objects around the vehicle, and to provide a driving support ECU configured to support the collision between the vehicle and the obstacle when it is determined that there is a possibility of a collision between the vehicle and the obstacle, when it is determined that there is a possibility of a collision between the vehicle and the obstacle. When the driving assistance ECU determines that the obstacle is a preceding vehicle which is temporarily stopped and the preceding vehicle is started, the driving assistance ECU executes at least one of a process for changing a determination condition of the possibility so as to easily determine that the obstacle is likely to exist and a process for improving an effect of the response control.

Description

Technical Field

[0001] The invention relates to an anti-collision device for reducing the possibility of collision between a vehicle and an obstacle. Background Art

[0002] As one type of collision avoidance device for vehicles such as automobiles, there is known a collision avoidance device that, when an obstacle is detected in front of the vehicle, determines the possibility of a collision between the vehicle and the obstacle, and when it is determined that there is such a possibility, performs response control such as automatic deceleration to reduce the possibility.

[0003] For example, the following Japanese Patent Laid-Open No. 11-039597 describes a collision avoidance device that detects a preceding vehicle in front of its own vehicle based on an image captured by a vehicle-mounted camera, determines the possibility of a collision between its own vehicle and the preceding vehicle, and displays the determination result on a display to notify the driver.

[0004] According to the collision avoidance device, even if there is an obstacle in front of the vehicle and the vehicle may collide with the obstacle, since response control such as automatic deceleration and notification of the possibility of collision is performed, the possibility of the vehicle colliding with the obstacle can be reduced. Summary of the invention

[0005] For example, when the own vehicle is traveling behind the preceding vehicle, the preceding vehicle and the own vehicle temporarily stop in front of the traffic light when the traffic light turns red, and the preceding vehicle starts moving when the traffic light turns green, the own vehicle also starts moving. However, if the preceding vehicle suddenly decelerates or stops immediately after starting due to congestion of vehicles in front of the preceding vehicle, the distance between the own vehicle and the preceding vehicle decreases rapidly, and the possibility of the own vehicle rear-ending the preceding vehicle increases.

[0006] In conventional collision avoidance devices such as the one described in Japanese Patent Application Laid-Open No. 11-039597, since the situation where the distance between the own vehicle and the preceding vehicle decreases rapidly is not considered, it is difficult to reduce the possibility of collision between the own vehicle and the preceding vehicle in such a situation.

[0007] The present invention provides a collision avoidance device which is improved to have a higher possibility of "reducing the possibility of a collision between the own vehicle and the preceding vehicle even when the distance between the own vehicle and the preceding vehicle is rapidly reduced" than in the past.

[0008] According to the present invention, there is provided an anti-collision device (100), comprising: a target object information acquisition device (17) for acquiring information of target objects around a own vehicle (102); and a control unit (driving assistance ECU 10), configured to determine the possibility of a collision between the own vehicle and the obstacle (S80, S100) when it is determined that there is an obstacle in front of the own vehicle based on the information acquired by the target object information acquisition device (S20), and when it is determined that the above possibility exists, execute response control (S90, S110) to reduce the above possibility.

[0009] The control unit (driving assistance ECU 10) is configured to, when it is determined that the obstacle is a temporarily stopped leading vehicle (114) (S230) and the leading vehicle has started (S250), execute at least one of the processing of changing the determination conditions of the above possibility in a manner that makes it easier to determine that the above possibility exists, and the processing of improving the effect of the response control (S70).

[0010] According to the above configuration, when it is determined that the obstacle is a temporarily stopped preceding vehicle and the preceding vehicle has started, at least one of a process of changing the determination condition of the possibility so as to make it easier to determine that the possibility exists and a process of improving the effect of the response control is executed.

[0011] When the determination condition of the above possibility is changed, it becomes easy to determine that the above possibility exists, so the response control is started in advance. As a result, the possibility of the vehicle rear-ending the preceding vehicle can be effectively reduced compared to the case where the determination condition of the above possibility is not changed. In addition, when the effect of the response control is improved, since the response control is effectively executed, the possibility of the vehicle rear-ending the preceding vehicle can be effectively reduced compared to the case where the effect of the response control is not improved.

[0012] In one technical solution of the present invention, the control unit (driving assistance ECU 10) is configured to calculate the distance (Lr) (S40) between the own vehicle and the preceding vehicle (114) based on the information obtained by the target object information acquisition device (17), and determine that the above-mentioned possibility exists (S80, S100) when the distance is less than the reference distance (Lrc1, Lrc2). Furthermore, the control unit is configured to change the determination condition of the above-mentioned possibility by increasing the reference distance (S70) when it is determined that the preceding vehicle has started (S250).

[0013] According to the above technical solution, when it is determined that the leading vehicle has started, the reference distance is increased and corrected, making it easier to determine that the distance between the own vehicle and the leading vehicle is less than the reference distance. Therefore, the determination condition of the above possibility can be changed in a manner that makes it easier to determine that there is a possibility of the above collision.

[0014] In another technical solution of the present invention, the response control includes automatic deceleration (S110) for automatically decelerating the own vehicle, and the control unit (driving assistance ECU10) is configured to improve the effect of the response control by increasing the deceleration of the automatic deceleration (S70) when it is determined that the leading vehicle has started (S250).

[0015] According to the above aspect, when it is determined that the preceding vehicle has started, the deceleration of the automatic deceleration is corrected to increase, and the own vehicle is decelerated effectively, thereby improving the effect of the countermeasure control for reducing the possibility of the above collision.

[0016] In another aspect of the present invention, the control unit (driving assistance ECU 10 ) is configured to terminate execution of the at least one of the above steps ( S300 ) when the elapsed time from the time point when the possibility is determined to exist is equal to or longer than a reference time (Tc).

[0017] According to the above technical solution, when the time elapsed from the time point when the possibility is determined to exist is equal to or longer than the reference time, the execution of the at least one is terminated, thereby reducing the possibility that the execution of the at least one is excessively continued.

[0018] In another aspect of the present invention, the control unit (driving assistance ECU 10 ) is configured to terminate execution of at least one of the above steps ( S300 ) when the travel distance of the own vehicle from the time point when the possibility is determined to exist is greater than a reference travel distance (Lvc).

[0019] According to the above technical solution, when the travel distance of the own vehicle from the time point when the possibility is determined to exist is greater than the reference travel distance, the execution of the at least one of the above is terminated, thereby reducing the possibility of excessive continuation of the execution of the at least one of the above.

[0020] In the above description, other objects, other features and incidental advantages of the present invention can be easily understood from the description of the embodiments of the present invention described below with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Features, advantages, and technical and industrial significance of exemplary embodiments of the present invention will be described below with reference to the accompanying drawings, in which like reference numerals represent like elements, and in which:

[0022] Figure 1 1 is a schematic diagram showing the structure of the collision avoidance device according to the embodiment.

[0023] Figure 2 This is a flowchart corresponding to the collision avoidance control program in the embodiment.

[0024] Figure 3 This is a flowchart corresponding to the flag control program in the implementation mode.

[0025] Figure 4 The diagram shows a situation in which the traffic light at the intersection is red, the preceding vehicle is stopped, and the own vehicle is stopped behind the preceding vehicle.

[0026] Figure 5 The diagram shows a situation where the traffic light at the intersection turns green, the preceding vehicle starts moving, and the own vehicle stops.

[0027] Figure 6 The diagram shows a situation in which a preceding vehicle starts, the own vehicle starts immediately after the preceding vehicle starts, and the preceding vehicle suddenly decelerates or stops immediately after starting due to congestion of vehicles ahead of the preceding vehicle or the like. DETAILED DESCRIPTION

[0028] Hereinafter, a collision avoidance device according to an embodiment of the present invention will be described in detail with reference to the drawings.

[0029] like Figure 1 As shown, the anti-collision device 100 according to the embodiment of the present invention is applicable to a vehicle 102, and includes a driving assistance ECU 10. The vehicle 102 is a vehicle capable of automatic driving, and includes a drive ECU 20, a brake ECU 30, and a meter ECU 50. An ECU refers to an electronic control unit (Electronic Control Unit) having a microcomputer as a main part. The vehicle 102 is recorded as the own vehicle 102 as needed.

[0030] The microcomputer of each ECU includes a CPU, ROM, RAM, a readable and writable non-volatile memory (N / M), and an interface (I / F). The CPU implements various functions by executing instructions (programs, routines) stored in the ROM. Moreover, these ECUs are connected to each other via CAN (Controller Area Network) 104 in a manner that can exchange data (can communicate). Therefore, the detection values ​​of sensors (including switches) connected to a specific ECU are also sent to other ECUs.

[0031] The driving assistance ECU 10 is a control device that is the core of driving control for driving assistance such as collision avoidance control, following vehicle distance control, and lane keeping control. In the embodiment, as described in detail later, the driving assistance ECU 10 cooperates with other ECUs to perform collision avoidance control for the vehicle 102. In addition, following vehicle distance control (adaptive cruise control) is abbreviated as ACC.

[0032] The driving support ECU 10 is connected to a camera sensor 12, a radar sensor 14, a sonar device 16, and a setting operator 18. The camera sensor 12 and the radar sensor 14 include a plurality of camera devices and a plurality of radar devices, respectively, and the sonar device 16 includes a plurality of sonars. The camera sensor 12, the radar sensor 14, and the sonar device 16 function as a target object information acquisition device 17 that acquires target object information around the vehicle 102.

[0033] Although not shown, each camera device of the camera sensor 12 includes a camera unit for photographing the surroundings of the vehicle 102 and a recognition unit for analyzing the image data photographed by the camera unit to recognize targets such as white lines on the road and other vehicles. The recognition unit supplies information related to the recognized target to the driving assistance ECU 10 at predetermined intervals.

[0034] Each radar device of the radar sensor 14 is equipped with a radar transceiver and a signal processing unit (not shown). The radar transceiver transmits radio waves in the millimeter wave band (hereinafter referred to as "millimeter waves") and receives millimeter waves (i.e., reflected waves) reflected by three-dimensional objects (such as other vehicles, bicycles, etc.) within the transmission range. The signal processing unit supplies information indicating the distance between the own vehicle and the three-dimensional object, the relative speed between the own vehicle and the three-dimensional object, and the relative position (direction) of the three-dimensional object relative to the own vehicle to the driving assistance ECU 10 at predetermined intervals based on the phase difference between the transmitted millimeter wave and the received reflected wave, the attenuation level of the reflected wave, and the time from the transmission of the millimeter wave to the reception of the reflected wave. In addition, LiDAR (Light Detection And Ranging) can be used instead of the radar sensor 14 or in addition to the radar sensor 14.

[0035] The sonar device 16 includes a plurality of sonars, and these sonars are installed at a plurality of positions of the outer periphery of the vehicle 102, such as the left front end, the right front end, the left rear end, and the right rear end. Each sonar is configured to transmit ultrasonic waves in a direction away from the vehicle 102, receive ultrasonic waves transmitted by its own sonar and reflected by an object, that is, direct waves, and receive ultrasonic waves transmitted by other sonars and reflected by an object, that is, indirect waves. In addition, each sonar is configured to output a signal indicating the peak value of a reception voltage corresponding to the received ultrasonic wave to the control device of the sonar device 16, thereby outputting a signal indicating the peak value of the received ultrasonic wave.

[0036] The control device of the sonar device 16 determines that the corresponding sonar has received the ultrasonic wave when the peak value is greater than the reference value. In addition, the control device of the sonar device 16 estimates the distance between the object reflecting the direct wave and the indirect wave and the vehicle 102 and the direction of the object relative to the vehicle based on the flight time of the direct wave and the indirect wave.

[0037] Set the operator 18 as Figure 1 The steering wheel shown in the figure is arranged in a position where it can be operated by the driver, and is operated by the driver. Figure 1 Although not shown, the setting operator 18 includes a driving assist switch. As described in detail later, the driving assist ECU 10 executes the collision avoidance control when the driving assist switch is turned on.

[0038] The drive ECU 20 is connected to a drive device 22 that accelerates the vehicle 102 by applying a driving force to a drive wheel 24. The drive ECU 20 normally controls the drive device 22 in such a manner that the driving force generated by the drive device 22 changes according to a driving operation performed by the driver, and when receiving a command signal from the driving assistance ECU 10, controls the drive device 22 based on the command signal.

[0039] The brake ECU 30 is connected to a brake device 32 for decelerating the vehicle 102 by applying a braking force to the wheels 34. The brake ECU 30 normally controls the brake device 32 in such a manner that the braking force generated by the brake device 32 changes according to the brake operation performed by the driver, and when receiving a command signal from the driving assistance ECU 10, the brake device 32 is controlled based on the command signal to perform automatic braking.

[0040] Thus, the brake ECU 30 and the brake device 32 cooperate with each other to function as an automatic brake device 36. In addition, when a braking force is applied to the wheel due to collision avoidance control, etc., Figure 1 The brake lights (not shown) light up.

[0041] The meter ECU 50 is connected to a touch panel type display 52 that displays the status of control performed by the driving assistance ECU 10 and an alarm device 54 that issues an alarm. The display 52 may be, for example, a multi-information display that displays meters and various information, or may be a display of a navigation device 80 described later. As described later, when receiving a signal from the driving assistance ECU 10, the display 52 displays the status of the collision avoidance control.

[0042] The alarm device 54 is activated when it is determined that the vehicle 102 is likely to collide with an obstacle, and performs "issuance of an alarm" as one of the collision prevention controls, that is, "issuance of an alarm to the effect that the vehicle 102 is likely to collide with an obstacle". The alarm device 54 may be any of an alarm device that issues a visual alarm such as an alarm light, an alarm device that issues an auditory alarm such as an alarm buzzer, and an alarm device that issues a physical alarm such as seat vibration, or any combination thereof.

[0043] The driving operation sensor 60 and the vehicle state sensor 70 are both connected to the CAN 104. The information detected by the driving operation sensor 60 and the vehicle state sensor 70 (referred to as sensor information) is sent to the CAN 104. The sensor information sent to the CAN 104 can be used appropriately in each ECU. In addition, the sensor information may also be information of a sensor connected to a specific ECU, and is sent from the specific ECU to the CAN 104.

[0044] The driving operation sensor 60 includes a driving operation amount sensor for detecting the operation amount of the accelerator pedal, a braking operation amount sensor for detecting the master cylinder pressure or the pedal force on the brake pedal, and a brake switch for detecting the operation of the brake pedal. In addition, the driving operation sensor 60 includes a steering angle sensor for detecting the steering angle, a steering torque sensor for detecting the steering torque, and the like.

[0045] The vehicle state sensor 70 includes a vehicle speed sensor for detecting a vehicle speed V of the vehicle 102, a longitudinal acceleration sensor for detecting acceleration in the longitudinal direction of the vehicle, a lateral acceleration sensor for detecting lateral acceleration of the vehicle, and a yaw rate sensor for detecting a yaw rate of the vehicle.

[0046] Furthermore, the navigation device 80 is also connected to the CAN 104. The navigation device 80 includes a GPS receiver for detecting the position of the vehicle 102, a storage device for storing map information and road information, and a communication device for acquiring the latest information of the map information and road information from the outside. In particular, the road information may include information on positions where the vehicle may temporarily stop, such as intersections, T-junctions, and crosswalks. In addition, the navigation device 80 may not be provided.

[0047] In the embodiment, the ROM of the driving assistance ECU 10 stores Figure 2 The anti-collision control program corresponding to the flowchart shown in FIG. 1 is also described in detail in the embodiment. Figure 3 The flowchart shown corresponds to the flag control program.

[0048] <Collision Avoidance Control( Figure 2 )>

[0049] Next, refer to Figure 2 The flowchart shown in FIG. 1 is used to explain the collision avoidance control in the embodiment. When the driving assist switch is turned on, the CPU of the driving assist ECU 10 repeatedly executes the control at predetermined intervals. Figure 2 The flowchart of the collision avoidance control is shown.

[0050] First, in step S10, the CPU determines whether the vehicle speed V of the vehicle 102 is below the reference value Vc (positive constant) for low vehicle speed determination. If the determination is "yes", the control proceeds to step S30, and if the determination is "no", that is, when the vehicle is traveling at a medium or high speed, the control proceeds to step S20.

[0051] In step S20, the CPU performs pre-collision safety control (hereinafter referred to as PCS control) in a manner known in the art. In PCS control, the possibility of a collision between the own vehicle and the preceding vehicle is determined based on, for example, the distance between the own vehicle and the preceding vehicle detected by the camera sensor 12 or the radar sensor 14 and the relative speed of the own vehicle relative to the preceding vehicle. When it is determined that there is a possibility of a collision, an alarm is issued by the alarm device 54, and the own vehicle is decelerated by automatic braking by the automatic braking device 36, thereby preventing a collision.

[0052] In step S30, the CPU determines whether there is an obstacle in front of the vehicle based on information about the target in front of the vehicle 102 acquired by the sonar device 16 or the radar sensor 14 of the target information acquisition device 17. If the determination is "no", the present control is temporarily terminated, and if the determination is "yes", the present control proceeds to step S40.

[0053] In step S40 , the CPU calculates the distance Lr from the vehicle 102 to the obstacle and the relative speed Vr of the vehicle 102 to the obstacle based on the information of the target object in front of the vehicle 102 acquired by the sonar device 16 or the radar sensor 14 .

[0054] In step S50, the CPU calculates the target stop inter-vehicle distance Lst, for example, in such a manner that the smaller the ratio Lr / Vr of the distance Lr to the relative speed Vr, the larger the target stop inter-vehicle distance Lst. In addition, the distance Lr between the vehicle 102 and the obstacle when the vehicle 102 is stopped by automatic deceleration is taken as the stop inter-vehicle distance Ls, and the target stop inter-vehicle distance Lst is the target value of the stop inter-vehicle distance Ls. In addition, the CPU calculates the target deceleration Gbt of the vehicle 102 for making the stop inter-vehicle distance Ls the target stop inter-vehicle distance Lst based on the current distance Lr, the target stop inter-vehicle distance Lst, and the current vehicle speed V. In addition, the target deceleration Gbt is calculated in such a manner that the higher the relative speed Vr, the larger the target deceleration Gbt, and the smaller the difference Lr-Lst between the distance Lr and the target stop inter-vehicle distance Lst, the larger the target deceleration Gbt.

[0055] In step S60, the CPU determines whether to Figure 3The routine shown controls whether the flag Fa is "1", that is, whether it is determined that the temporarily stopped preceding vehicle has started. When it is determined as "No", the control proceeds to step S80, and when it is determined as "Yes", the control proceeds to step S70.

[0056] In step S70, the CPU increases and corrects the target deceleration Gbt by increasing and correcting the target stopping vehicle distance Lst. In addition, the CPU increases and corrects the first reference distance Lrc1 and the second reference distance Lrc2 used in the judgment of steps S80 and S100 described later. The first reference distance Lrc1 is larger than the second reference distance Lrc2. Therefore, the judgment conditions of the possibility in steps S80 and S100 are changed in a manner that makes it easier to judge that there is a possibility of a collision between the own vehicle and the obstacle.

[0057] In addition, the increase correction may be performed by multiplying by a correction coefficient greater than 1, or by adding a corresponding correction amount (positive constant). In addition, the increase correction of the target deceleration Gbt may not be performed in a manner other than "increasing the target stop inter-vehicle distance Lst". Furthermore, the display 52 may be operated by outputting a command signal to the meter ECU 50, and the message "the issuance of the early start warning and automatic deceleration" may be notified.

[0058] In step S80, the CPU determines whether the distance Lr from the vehicle 102 to the obstacle is less than the first reference distance Lrc1, that is, whether there is a possibility that the vehicle 102 will collide with the obstacle. If the determination is "No", the control is temporarily terminated, and if the determination is "Yes", the control proceeds to step S90.

[0059] In step S90, the CPU operates the alarm device 54 by outputting a command signal to the meter ECU 50, thereby issuing an alarm to the effect that "the vehicle 102 may collide with an obstacle". In addition, the CPU operates the display 52 by outputting a command signal to the meter ECU 50, thereby notifying the message that "the vehicle 102 may collide with an obstacle".

[0060] In step S100, the CPU determines whether the distance Lr from the vehicle 102 to the obstacle is less than or equal to the second reference distance Lrc2. If the determination is "NO", the present control is temporarily terminated, and if the determination is "YES", the present control proceeds to step S110.

[0061] In step S110 , the CPU outputs command signals to the drive ECU 20 and the brake ECU 30 to reduce the drive force of the drive device 22 and activate the automatic brake device 36 to apply braking force to the vehicle 102 , thereby performing automatic deceleration so that the vehicle deceleration reaches the target deceleration Gbt.

[0062] As can be seen from the above description, in the embodiment, the “response control for reducing the possibility of collision between the vehicle and the obstacle” is “issuance of an alarm by the operation of the alarm device 54”, “reduction of the driving force of the drive device 22”, and “automatic deceleration by applying the braking force of the automatic brake device 36”. However, any of the response controls may be omitted.

[0063] <Logo Control( Figure 3 )>

[0064] Next, refer to Figure 3 The flowchart shown in FIG. 1 is used to explain the flag control in the embodiment. When the driving assist switch is turned on, the CPU of the driving assist ECU 10 repeatedly executes the flag control at predetermined intervals. Figure 3 The flag control is shown in the flowchart. In addition, the flags Fa and Fb are reset to 0 when the flag control starts.

[0065] First, in step S210, the CPU determines whether "the flag Fa is 1", that is, whether "the preceding vehicle that has been temporarily stopped has started." If it is determined to be "yes", the control proceeds to step S280, and if it is determined to be "no", the control proceeds to step S220.

[0066] In step S220, the CPU determines whether "the flag Fb is 1", that is, whether "it has been determined in step S230 described later that there is a preceding vehicle that is temporarily stopped in front of the own vehicle". If the determination is "yes", the control proceeds to step S250, and if the determination is "no", the control proceeds to step S230.

[0067] In step S230, the CPU determines whether the vehicle speed V of the own vehicle is less than the vehicle speed reference value Vs and whether there is a preceding vehicle that is temporarily stopped in front of the own vehicle based on the information obtained by the target object information acquisition device 17. If the determination is "no", this control is temporarily terminated, and if the determination is "yes", the flag Fb is set to 1 in step S240, and then this control enters step S250.

[0068] The vehicle speed reference value Vs is a reference value for determining an extremely low vehicle speed and is a positive constant smaller than the reference value Vc for low vehicle speed determination used in the determination in step S10. The determination in step S230 may be the following determination: whether the own vehicle is temporarily stopped and there is a preceding vehicle that is temporarily stopped ahead of the own vehicle.

[0069] In step S250, the CPU determines whether the temporarily stopped preceding vehicle has started. If the determination is "NO", the present control is temporarily terminated, and if the determination is "YES", the present control proceeds to step S260.

[0070] In step S260, the CPU variably sets the reference time Tc and reference travel distance Lvc used in the determination of steps S280 and S290 described later, respectively, based on at least one of the type of road ahead of the position where the own vehicle and the preceding vehicle temporarily stop and the degree of vehicle congestion.

[0071] In addition, when the road ahead is a crossroad or a T-shaped road, the reference time Tc and the reference travel distance Lvc may be set so that the wider the road intersecting the road where the vehicle is traveling is and the more lanes there are, the greater the reference time Tc and the reference travel distance Lvc are. When the road ahead is a crosswalk or a road with a temporary stop line, the reference time Tc and the reference travel distance Lvc may be set to values ​​smaller than when the road ahead is a crossroad or a T-shaped road. Furthermore, the reference time Tc and the reference travel distance Lvc may be set so that the greater the congestion level of the vehicle ahead of the vehicle is, the greater the reference time Tc and the reference travel distance Lvc are.

[0072] In step S270 , the CPU sets the flag Fa to 1, and resets the flag Fb to 0.

[0073] In step S280, the CPU determines whether the time elapsed from the time point at which it is determined in step S80 that the vehicle 102 may collide with the obstacle is greater than the reference time Tc. If the determination is "yes", the control proceeds to step S300, and if the determination is "no", the control proceeds to step S290. In addition, the elapsed time may also be the time elapsed from the time point at which it is determined in step S100 that the vehicle 102 may collide with the obstacle.

[0074] In step S290, the CPU determines whether the travel distance of the vehicle from the time point when it is determined in step S80 that there is a possibility of collision between the vehicle 102 and the obstacle is greater than the reference travel distance Lvc. If it is determined to be "no", the control is temporarily terminated. If it is determined to be "yes", in step S300, the flag Fa is reset to 0, and then the control is temporarily terminated. In addition, the travel distance may also be the travel distance from the time point when it is determined in step S100 that there is a possibility of collision between the vehicle 102 and the obstacle.

[0075] <Work and Effects of Implementation Method>

[0076] <When the preceding vehicle and the own vehicle stop ( Figure 4 )>

[0077] For example, Figure 4 The traffic light 112 at the intersection 110 is red, the preceding vehicle 114 is stopped, and the own vehicle 102 is stopped behind the preceding vehicle. Figure 4 In the case of the situation shown, it is determined as "No" in steps S210 and S220 and "Yes" in step S230, so in step S240, flag Fb is set to 1. It is determined as "No" in step S250, so steps S260 and S270 are not executed.

[0078] Thus, the flag Fa is maintained at 0, and therefore, it is determined as "No" in step S60, and step S70 is not executed. Therefore, the first reference distance Lrc1 and the second reference distance Lrc2 are not corrected to increase, and the target deceleration Gbt is not corrected to increase. The first reference distance Lrc1 and the second reference distance Lrc2 are respectively maintained at the standard values ​​to perform the determinations of steps S80 and S100.

[0079] <When the leading vehicle starts moving ( Figure 5 )>

[0080] Figure 5 The figure shows a situation where the traffic light 112 at the intersection 110 turns green, the preceding vehicle 114 starts, and the own vehicle 102 stops. Figure 5 In the case of the situation shown, Figure 4 Similarly, in the case of the situation shown, first, it is determined as "No" in steps S210 and S220, and it is determined as "Yes" in step S230, so in step S240, the flag Fb is set to 1. Then, it is determined as "Yes" in step S250, and the reference time Tc and the reference travel distance Lvc are set according to the type of the road ahead in step S260, and the flag Fa is set to 1 and the flag Fb is reset to 0 in step S270.

[0081] Therefore, it is determined as "yes" in step S60, and step S70 is executed, thereby increasing and correcting the first reference distance Lrc1 and the second reference distance Lrc2. That is, the determination conditions of the possibility in steps S80 and S100 are changed in a manner that makes it easier to determine that there is a possibility of a collision between the own vehicle and the obstacle. As a result, the determination of steps S80 and S100 is performed using the first reference distance Lrc1 and the second reference distance Lrc2 that have been respectively increased and corrected, so that compared with the case where the first reference distance and the second reference distance are standard values, it is determined as "yes" earlier.

[0082] <When the leading vehicle suddenly decelerates or stops just after starting ( Figure 6 )>

[0083] Figure 6 The preceding vehicle 114 starts, and the own vehicle 102 starts immediately after the preceding vehicle 114 starts. However, the preceding vehicle 114 decelerates or stops immediately after starting due to congestion of vehicles in front of the preceding vehicle 114. Figure 6 In the illustrated situation, the distance between the own vehicle 102 and the preceding vehicle 114 is rapidly decreasing, so the possibility that the own vehicle will rear-end the preceding vehicle becomes high.

[0084] However, according to the embodiment, as described above, compared with the case where the first reference distance and the second reference distance are standard values, the determination in steps S80 and S100 is made "yes" in advance, so the alarm in step S90 and the automatic deceleration in step S110 are started in advance. As a result, compared with the previous case where the first reference distance Lrc1 and the second reference distance Lrc2 are not increased and corrected, the possibility of the own vehicle rear-ending the preceding vehicle can be effectively reduced.

[0085] In addition, according to the embodiment, since not only the first reference distance Lrc1 and the second reference distance Lrc2 are increased and corrected, but also the target deceleration Gbt is increased and corrected, the own vehicle can be decelerated at a high deceleration. Thus, compared with the previous situation where the target deceleration Gbt is not increased and corrected, the possibility of the own vehicle rear-ending the leading vehicle can be effectively reduced.

[0086] In addition, according to the embodiment, when the time elapsed from the time point when it is determined that there is a possibility of the vehicle 102 colliding with the obstacle is greater than the reference time Tc (S280), the execution of the response control (S80 and S100) for reducing the possibility of the vehicle 102 colliding with the preceding vehicle as an obstacle is terminated (S300). This can reduce the possibility of executing the response control for an excessively long time.

[0087] In addition, according to the embodiment, when the travel distance of the vehicle from the time point when it is determined that there is a possibility of the vehicle 102 colliding with the obstacle is greater than the reference travel distance Lvc (S290), the execution of the response control for reducing the possibility of the vehicle 102 colliding with the preceding vehicle as an obstacle is terminated (S300). Thus, by doing so, the possibility of executing the response control for an excessively long time can also be reduced.

[0088] Furthermore, according to an embodiment, in step S260, the reference time Tc and the reference running distance Lvc are variably set according to at least one of the type of road ahead of the position where the vehicle and the preceding vehicle are temporarily stopped and the degree of congestion of the vehicle. Thus, compared with the case where the reference time Tc and the reference running distance Lvc are constant, the possibility of executing the response control for an excessively long time and the possibility of insufficient time for executing the response control can be reduced. In addition, step S260 may be omitted. That is, the reference time Tc and the reference running distance Lvc may also be constant.

[0089] As mentioned above, although the specific embodiment of the present invention has been described in detail, it is obvious to those skilled in the art that the present invention is not limited to the above-mentioned embodiment, and other various embodiments can be implemented within the scope of the present invention.

[0090] For example, in the above embodiment, in step S70, the target deceleration Gbt, the first reference distance Lrc1, and the second reference distance Lrc2 are corrected to increase. However, only the target deceleration Gbt, or only the first reference distance Lrc1 and the second reference distance Lrc2 may be corrected to increase.

[0091] In the above-mentioned embodiment, in step S280, it is determined whether the elapsed time is greater than or equal to the reference time Tc, and in step S290, it is determined whether the travel distance of the vehicle is greater than or equal to the reference travel distance Lvc. However, step S280 or S290 may be omitted. In this case, the setting of the reference time Tc or the reference travel distance Lvc corresponding to the omitted determination is omitted (step S260).

[0092] In addition, in the above-mentioned embodiment, the effect of the alarm as one of the response controls is not improved even if the flag Fa is 1. However, the appeal effect of the alarm may be improved when the flag Fa is 1. For example, when the alarm is issued by the intermittent sound of the buzzer, the intermittent sound of the buzzer may be changed to a continuous sound.

[0093] Furthermore, in the above-mentioned embodiment, the alarm is issued and the vehicle is automatically decelerated as the response control. However, the response control may also be the alarm or the vehicle is automatically decelerated, in which case the effect of the response control can be set higher than when the response control is the alarm or the vehicle is automatically decelerated.

Claims

1. A collision avoidance device, comprising a target information acquisition device and a control unit, The target object information acquisition device acquires information of target objects around the vehicle. The control unit is configured to, when it is determined based on the information obtained by the target object information acquisition device that there is an obstacle in front of the own vehicle, determine the possibility of the own vehicle colliding with the obstacle, and when it is determined that there is such a possibility, execute a response control to reduce the possibility, The control unit is configured to, when it is determined that the obstacle is a temporarily stopped preceding vehicle and the preceding vehicle has started, execute at least one of a process of changing the determination condition of the possibility in a manner that makes it easier to determine that the possibility exists and a process of improving the effect of the response control.

2. The anti-collision device according to claim 1, The control unit is configured to obtain a distance between the own vehicle and the preceding vehicle based on the information obtained by the target object information acquisition device, and determine that the possibility exists when the distance is equal to or less than a reference distance. Furthermore, the control unit is configured to change the determination condition of the possibility by correcting the reference distance to increase the distance when it is determined that the preceding vehicle has started.

3. The anti-collision device according to claim 1, The response control includes automatic deceleration for automatically decelerating the own vehicle, The control unit is configured to improve the effect of the response control by correcting the deceleration of the automatic deceleration to increase when it is determined that the leading vehicle has started.

4. The anti-collision device according to claim 1, The control unit is configured to terminate execution of the at least one when a time elapsed from a time point when it is determined that the possibility exists is equal to or longer than a reference time.

5. The anti-collision device according to claim 1, The control unit is configured to terminate execution of the at least one when a travel distance of the own vehicle from a time point when it is determined that the possibility exists is equal to or greater than a reference travel distance.

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