Exit assistance device

Abstract

The disembarking assistance device includes a target information acquisition device 12 that acquires target information related to targets present behind the vehicle, and a control unit 10 that can execute disembarking assistance control. The control unit determines whether an obstructing target that may obstruct the safe disembarking of an occupant while the vehicle is stopped is detected based on the target information, and if a disembarking assistance condition that is established when at least an obstructing target is detected is established, determines whether a specific condition that is established when at least a part of the obstructing target is located within the rear vehicle width region is established, and executes disembarking assistance control when the specific condition is not established, and does not execute disembarking assistance control when the specific condition is established.

Description

[Technical field]

[0001] The present invention relates to a vehicle dismounting assistance device capable of suppressing unnecessary operation of a vehicle dismounting assistance control. [Background technology]

[0002] Conventionally, there has been known a vehicle dismounting support device capable of executing a vehicle dismounting support control for supporting a vehicle occupant to safely dismount from a vehicle. The vehicle dismounting support device is configured to execute the vehicle dismounting support control when, for example, an obstruction target that may obstruct the safe dismounting of the occupant while the vehicle is stopped (in other words, passing by the side of the vehicle) is detected and an intention of the occupant to dismount is detected.

[0003] For example, the vehicle door control device of Japanese Patent Publication No. 2007-138457 is equipped with a passing object detection means for detecting an object passing along the side of the vehicle, and is configured to notify the occupant of the presence of an object when the passing object detection means detects an object passing along the side of the vehicle while the vehicle's sliding door is in an open state and to suppress the opening operation of the sliding door. Summary of the Invention

[0004] The dismounting support device includes a "target information acquisition device that detects targets present behind the vehicle and acquires information about the detected targets as target information," and determines whether the detected target is an obstruction target based on the target information acquired by the device. Typically, the dismounting support device determines whether a target is an obstruction target as follows.

[0005] That is, the dismounting support device sets virtual lines extending from the left and right rear corners of the vehicle in the vehicle widthwise outward direction (i.e., the outward direction in the vehicle width direction) as intersection determination lines during the stopped period.Then, the moving direction of the target is calculated based on the target information, and it is determined whether the target will pass the intersection determination line within a predetermined time if it continues to move along the moving direction.If it is determined that the target will pass within the predetermined time, the dismounting support device determines that the target is an obstruction target.

[0006] In this way, the dismounting support control is executed for the object determined to be an obstruction object, thereby reducing the possibility that the door or the occupant will come into contact with the obstruction object. However, on the other hand, if the dismounting support control is executed in a situation where the control is not required, it may cause inconvenience to the occupant or hinder the occupant from getting off the vehicle safely. Here, depending on the detection accuracy of the object information acquisition device, the accuracy of the object information may decrease, and an error may occur in the calculation result of the moving direction of the object. As a result, even if the object continues to move along the current moving direction, it may not actually intersect with the crossing judgment line, but it may be determined to be an obstruction object that passes through the crossing judgment line within a predetermined time. That is, the above-mentioned "situation where dismounting support control is not required" is a situation where an object that does not actually correspond to an obstruction object is erroneously detected as an obstruction object due to an error occurring in the calculation result of the moving direction of the object. For this reason, it is required to suppress unnecessary operation of the dismounting support control and improve the reliability of the control.

[0007] The present invention has been made to address the above-mentioned problems. That is, an object of the present invention is to provide a vehicle dismounting assistance device capable of suppressing unnecessary operation of the vehicle dismounting assistance control.

[0008] The disembarking assistance device according to the present invention (hereinafter referred to as the "device of the present invention") is a target information acquisition device (12) that detects a target present behind the vehicle and acquires information about the detected target as target information; A control unit (10) capable of executing a vehicle exit assistance control for assisting a passenger in safely exiting the vehicle; Equipped with. A portion of a front end of an obstacle object that may hinder the safe disembarking of the occupant while the vehicle is stopped that is closest to the vehicle in a vehicle width direction of the vehicle is defined as a nearby portion (np); If imaginary lines having a predetermined length that are located on a reference axis (y-axis) passing through the left and right rear corners of the vehicle and that extend from the left and right rear corners in a vehicle width outward direction are defined as intersection determination lines (LL, LR), The control unit (10) When an intersection point between an extension line extending from the adjacent portion (np) along the moving direction of the detected target and the reference axis (y-axis) is located on the intersection determination line (LL, LR), if a predicted time (TTC) that is predicted to be required for the target to reach the intersection point is equal to or less than a predetermined time threshold (TTCth), the target is detected as an obstruction target and it is determined that an obstruction target has been detected; determining whether or not a dismounting assistance condition is satisfied when at least the obstruction object is detected; When the dismounting assistance condition is satisfied, at least a part of the obstruction target is located within a rear vehicle width region (Rvw) that is a region between a virtual line (L1) extending from a left rear corner of the host vehicle in a rear direction (-x-axis direction) in the fore-and-aft direction (x-axis direction) of the host vehicle and a virtual line (L2) extending from a right rear corner of the host vehicle in the rear direction (-x-axis direction). and the magnitude of the change in the position of the intersection per unit time (|Δy|) is equal to or greater than a predetermined change threshold (Δyth). determining whether a specific condition is satisfied when When the specific condition is not satisfied, the vehicle dismounting assistance control is executed. When the specific condition is satisfied, the vehicle dismount assistance control is not executed. It is structured as follows.

[0009] A conventional disembarking assistance device executes disembarking assistance control when an execution condition is satisfied, which is satisfied when, for example, an obstruction target is detected while the vehicle is stopped and an occupant's intention to disembark is detected. With this configuration, even when a target that is not actually an obstructing target is erroneously detected as an obstructing target due to an error in the calculation result of the moving direction, the disembarking assistance control is executed when the execution condition is satisfied, which causes unnecessary operation.

[0010] Here, the inventors of the present application have discovered that when an object is erroneously detected as an obstruction object due to an error in the calculation result of its movement direction, the object tends to be moving in an area extending directly behind the vehicle. In addition, the inventors of the present application have found that when a target is erroneously detected as an obstructing target due to an error in the calculation result of its moving direction, the magnitude of the change per unit time in the position of the intersection between the extension line extending from the nearby part along the moving direction of the target and the reference axis tends to be relatively large. Based on this knowledge, the present invention device does not immediately execute the vehicle exit assistance control when the vehicle exit assistance condition is satisfied, but executes the vehicle exit assistance control when a specific condition is satisfied, i.e., when at least a part of the obstruction object is located within the rear vehicle width region of the vehicle. and the magnitude of the change in the position of the intersection per unit time is equal to or greater than a change threshold value. The vehicle disembarking assistance control is configured to determine whether a condition that is satisfied when the specific condition is not satisfied is satisfied. If the specific condition is not satisfied, it is determined that the possibility that the target has been erroneously detected as an obstruction target is low, and to execute the vehicle disembarking assistance control, and if the specific condition is satisfied, it is determined that the possibility that the target has been erroneously detected as an obstruction target due to an error in the calculation result of the moving direction of the target is high, and to not execute the vehicle disembarking assistance control.

[0011] According to this configuration, when dismount assistance control is actually required, the control can be appropriately executed while unnecessary operation of the control can be suppressed, thereby improving the reliability of the dismount assistance control.

[0014] In one aspect of the invention, The control unit (10) Furthermore, it is determined that the specific condition is satisfied when a longitudinal component (vx) of the velocity (v) of the obstruction object relative to the host vehicle is greater than 0 and less than a predetermined velocity threshold (vxth), and / or when the longitudinal component (dx) of the deceleration (d) of the obstruction object is equal to or greater than a predetermined deceleration threshold (dxth). It is structured as follows.

[0015] The inventors of the present application have found that when an object is erroneously detected as an obstruction object due to an error in the calculation result of its moving direction, the object tends to move at a speed at which the speed of the "forward / rearward component of the host vehicle" is a relatively small value, and / or at a deceleration at which the deceleration of the forward / rearward component is a relatively large value. Based on this finding, in one aspect of the present invention, the specific condition is further configured to be satisfied when the forward / rearward component of the speed of the obstruction object is greater than 0 and less than a speed threshold value, and / or the forward / rearward component of the deceleration of the obstruction object is equal to or greater than a deceleration threshold value. With this configuration, the accuracy of determining whether the dismounting assistance control is unnecessary is further improved, and the dismounting assistance control can be more appropriately executed.

[0016] In the above description, in order to facilitate understanding of the invention, the symbols used in the embodiments are added in parentheses to the constituent elements of the invention corresponding to the embodiments, but each constituent element of the invention is not limited to the embodiment defined by the said symbols. [Brief description of the drawings]

[0017] [Figure 1] 1 is a schematic configuration diagram of an alighting support device (embodiment device) according to an embodiment of the present invention. [Diagram 2]FIG. 2 is a diagram showing a three-dimensional object detection range of a radar sensor provided in the embodiment of the present invention, and is a diagram for explaining a method of calculating the TTC of a target detected by the radar sensor. [Diagram 3] 10 is a diagram for explaining a specific condition, and is a diagram illustrating a case in which unnecessary operation of the warning control is suppressed when the warning condition is satisfied. FIG. [Figure 4] 4 is a flowchart showing a routine executed by a CPU of a vehicle dismounting support ECU of the embodiment of the present invention. [Diagram 5] 4 is a flowchart showing a routine executed by a CPU. [Figure 6] 4 is a flowchart showing a routine executed by a CPU. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] (composition) Hereinafter, a vehicle disembarking assistance device according to an embodiment of the present invention (hereinafter also referred to as "the embodiment device") will be described with reference to the drawings. As shown in FIG. 1, the embodiment device includes a vehicle disembarking assistance ECU 10, and a vehicle speed sensor 11, a radar sensor 12, a door opening / closing sensor 13, and a buzzer 20 connected thereto. The vehicle disembarking assistance ECU 10 includes a microcomputer as a main component. ECU stands for Electronic Control Unit. The microcomputer includes a CPU, a ROM, a RAM, an interface (I / F), etc., and the CPU is adapted to realize various functions by executing instructions (programs, routines) stored in the ROM. Hereinafter, a vehicle equipped with the embodiment device will be referred to as a "host vehicle."

[0019] The getting-off support ECU 10 is configured to acquire signals generated or output by the sensors 11 to 13 at predetermined intervals and control the buzzer 20 based on the acquired signals. Hereinafter, the getting-off support ECU 10 is also simply referred to as "ECU 10."

[0020] The vehicle speed sensor 11 generates a signal corresponding to the traveling speed of the host vehicle (hereinafter referred to as "vehicle speed"). The ECU 10 acquires the signal generated by the vehicle speed sensor 11 and calculates the vehicle speed based on the signal. When the vehicle speed is zero, the ECU 10 determines that the host vehicle is in a stopped state (hereinafter also referred to as "parked").

[0021] The radar sensor 12 (target information acquisition device) has a function of acquiring information about three-dimensional objects (targets) present behind (directly behind and to the rear sides of) the vehicle. The three-dimensional objects are moving objects such as vehicles, bicycles, pedestrians, etc.

[0022] As shown in FIG. 2, the radar sensor 12 includes a left radar sensor 12L provided at a left rear corner of the host vehicle V and a right radar sensor 12R provided at a right rear corner of the host vehicle V. The radar sensor 12 irradiates millimeter wave band radio waves to the surroundings of the host vehicle. Specifically, the left radar sensor 12L irradiates radio waves to a range including a left region RL on the left rear side of the host vehicle, and the right radar sensor 12R irradiates radio waves to a range including a right region RR on the right rear side of the host vehicle. The left region RL and the right region RR are both shaped to become longer in the vehicle width outward direction and the vehicle width inward direction as they move away from the host vehicle V rearward. Note that in FIG. 2, the ratios of the regions RL and RR to the host vehicle V are changed for convenience.

[0023] When a three-dimensional object is present within the irradiation range of the radio wave, the radar sensor 12 receives a reflected wave from the three-dimensional object. The radar sensor 12 calculates the presence or absence of a three-dimensional object and the relative relationship between the vehicle and the three-dimensional object (the distance from the vehicle to the three-dimensional object, the orientation of the three-dimensional object relative to the vehicle, and the relative speed of the three-dimensional object relative to the vehicle, etc.) based on the irradiation timing and reception timing of the radio wave, etc. In other words, the radar sensor 12 detects a three-dimensional object present behind the vehicle. Hereinafter, the three-dimensional object detected by the radar sensor 12 (i.e., a three-dimensional object present in the region RL or RR) is also referred to as a "target". The radar sensor 12 outputs this information regarding the target to the ECU 10 as target information.

[0024] The sensor for acquiring the target information is not limited to the radar sensor 12. For example, a laser radar sensor, an ultrasonic sensor, and / or a camera sensor may be used instead of or in addition to the radar sensor 12. Alternatively, a sensor used for blind spot monitor control may be used as the radar sensor 12. The blind spot monitor control is a control for alerting the driver of the vehicle when a vehicle approaching the vehicle from behind (particularly a vehicle present in an area that is difficult to see with the side mirror) is detected.

[0025] Returning to FIG. 1, the description will be continued. The door opening / closing sensor 13 is provided on each of a plurality of doors (more specifically, side doors) of the vehicle. The door opening / closing sensor 13 detects the open / closed state of the door. When the door opening / closing sensor 13 detects that a door is in an open state, it generates an open signal indicating that the door is in an open state while the open state is detected. When the door opening / closing sensor 13 detects that a door is in a closed state, it generates a close signal indicating that the door is in a closed state while the closed state is detected. The ECU 10 detects whether each of these door opening / closing sensors 13 is generating an open signal or a close signal, and detects whether the door corresponding to that door opening / closing sensor 13 is in an open state or a closed state based on the detection result.

[0026] The buzzer 20 is built into a meter panel (not shown), and is configured to sound based on a drive command from the ECU 10.

[0027] (Details of operation) A conventional disembarking assistance device is configured to execute disembarking assistance control when an obstruction target that may obstruct a passenger from disembarking safely while the vehicle is stopped is detected and the passenger's intention to disembark is detected. With this configuration, there is a possibility that an object that is not actually an obstructing object may be erroneously detected as an obstructing object due to an error in the calculation result of the moving direction of the object, resulting in unnecessary disembarking assistance control being executed. Therefore, the inventors of the present application have configured the present embodiment device as follows, based on the knowledge that "errors are likely to occur in the calculation result of the moving direction of the target when the target is moving in an area extending directly behind the vehicle." That is, when an obstruction target is detected while the vehicle is stopped and an intention of the occupant to get off is detected, if a specific condition (described later) that is "a condition that is likely to be satisfied when the obstruction target is moving in an area extending directly behind the vehicle" is satisfied, the present embodiment device is configured to determine that the obstruction target is not actually an obstruction target and not to execute the dismounting support control. In this embodiment, the ECU 10 executes an alarm control as the dismounting support control. The alarm control is a control that executes a process of sounding the buzzer 20. The operation of the ECU 10 will be described in detail below.

[0028] The ECU 10 determines that the warning condition is satisfied when all of the following conditions 1 to 3 are satisfied. The warning condition corresponds to an example of a "vehicle dismount support condition." (Condition 1) The vehicle is stopped. (Condition 2) An interfering target is detected. (Condition 3) The door of the vehicle is open.

[0029] First, a description will be given of Condition 1. When the vehicle speed acquired from the vehicle speed sensor 11 is zero, the ECU 10 determines that Condition 1 is satisfied.

[0030] Next, condition 2 will be described. An obstruction target refers to a moving object that may approach the vehicle from behind and obstruct the safe disembarking of an occupant (in other words, pass by the side of the vehicle). The ECU 10 detects an obstruction target as follows. That is, when the ECU 10 determines that a target exists in the left region RL or the right region RR based on the target information acquired from the radar sensor 12, the ECU 10 calculates a predicted time required for the target to contact or come closest to the vehicle. Hereinafter, for convenience of explanation, this predicted time is also referred to as "TTC (Time To Collision)". When the TTC is equal to or less than a predetermined time threshold TTCth, the ECU 10 detects the target as an obstruction target and determines that condition 2 is satisfied.

[0031] A more detailed description will be given with reference to FIG. 2. FIG. 2 shows another vehicle Vt approaching the host vehicle V from behind. As shown in FIG. 2, when the host vehicle V is stopped (i.e., when condition 1 is satisfied), the ECU 10 sets an xy coordinate system with the origin being the center of the left and right rear corners of the host vehicle V. The x axis extends in the front-rear direction of the host vehicle V, and the y axis extends in the vehicle width direction (left-right direction) of the host vehicle V. In other words, the y axis can also be said to be an axis passing through the left and right rear corners of the host vehicle V. In this embodiment, the centers of the left and right rear corners of the host vehicle V coincide with the rear end center of the host vehicle V. The y axis corresponds to an example of a "reference axis."

[0032] In addition, when the host vehicle V is in a stopped state, the ECU 10 sets an intersection determination line L on the host vehicle V. The intersection determination line L is a virtual line set to calculate the TTC, and includes a left intersection determination line LL and a right intersection determination line LR. The left intersection determination line LL extends from the left rear corner of the host vehicle V in the -y-axis direction (vehicle width outer direction) on the y axis, and the right intersection determination line LR extends from the right rear corner of the host vehicle V in the +y-axis direction (vehicle width outer direction) on the y axis. The lengths of the left and right intersection determination lines LL and LR are the same (for example, about 1.3 [m]), and in this embodiment, are approximately equal to the lengths of the regions RL and RR in the y-axis direction at the left and right rear corners of the host vehicle V. The lengths of the left and right intersection determination lines LL and LR are set in advance by experiment or simulation so that "if a target passes any position on these determination lines LL and LR while an occupant of the host vehicle V is getting off, there is a possibility that the target will come into contact with the door or the occupant of the host vehicle V."

[0033] When the host vehicle V is in a stopped state, the ECU 10 calculates a velocity vector A of the target (another vehicle Vt in the example of FIG. 2) based on the target information, and sets the starting point of the vector A to the proximity portion np of the target. The proximity portion np is the portion of the front end of the target that is closest to the host vehicle V in the y-axis direction. The velocity vector A can be calculated, for example, by time differentiation of the target position (distance and direction).

[0034] When an extension line of the target's speed vector A intersects with either one of the left and right crossing judgment lines LL and LR (in other words, the intersection point between the extension line and the y-axis is located on the crossing judgment line L), the ECU 10 calculates "a time predicted to be required for the target to intersect with the crossing judgment line L (in other words, a time predicted to be required for the target to reach the intersection point between the extension line of the target's speed vector A and the crossing judgment line L)" as the TTC. The TTC can be calculated by using the target information, for example, by dividing "the distance from the nearby part np to the intersection point" by "the current speed of the target".

[0035] If the TTC when the target object will cross the left crossing judgment line LL in the future is equal to or less than TTCth, ECU10 determines that the target object may hinder the occupants from safely disembarking through the left door, and detects the target object as an obstruction target for the left door. On the other hand, if the TTC when the target will cross the right crossing judgment line LR in the future is less than or equal to TTCth, ECU10 determines that the target may hinder the occupants from safely disembarking through the right door, and detects the target as an obstruction target for the right door. In these cases, the ECU 10 determines that the condition 2 is satisfied.

[0036] On the other hand, if the target will cross either the left or right crossing judgment line LL or LR in the future but the TTC exceeds TTCth, ECU10 determines that the target is not likely to hinder the occupants from disembarking safely (at this time) and does not detect the target as an obstruction target. In contrast, if the extension line of the target's velocity vector A does not intersect with either the left or right intersection judgment line LL, LR (in other words, the intersection point between the extension line and the y-axis is not located on the intersection judgment line L), the TTC cannot be calculated, and therefore ECU 10 does not detect the target as an obstruction target. In these cases, the ECU 10 determines that the condition 2 is not satisfied.

[0037] 2, the other vehicle Vt will cross the right crossing judgment line LR in the future according to the current speed vector A. Therefore, the ECU 10 calculates the TTC for the other vehicle Vt, and detects the other vehicle Vt as an obstruction target for the right door when the TTC is equal to or less than TTCth, and does not detect the other vehicle Vt as an obstruction target when the TTC exceeds TTCth.

[0038] Note that the ECU 10 calculates the y coordinate of the intersection with the y axis even if the extension line of the target velocity vector A does not intersect with the intersection judgment line L. For this reason, if the y coordinates of the end points of the left and right intersection judgment lines LL and LR are defined as -Ly and Ly, respectively, and the vehicle width of the host vehicle V is defined as w, then "the extension line of the target velocity vector A intersects with either one of the left and right intersection judgment lines LL and LR" is equivalent to "the y coordinate of the intersection between the extension line of the target velocity vector A and the y axis satisfies -Ly≦y≦-w / 2 or w / 2≦y≦Ly."

[0039] Next, a description will be given of condition 3. When the ECU 10 determines, based on the signal acquired from the door opening / closing sensor 13, that the door on the side where the obstruction object is detected is open, the ECU 10 determines that condition 3 is satisfied.

[0040] When the warning condition is satisfied, the ECU 10 judges whether or not the specific condition is satisfied for the obstruction target that satisfies the warning condition. In general, the detection accuracy of the radar sensor 12 tends to decrease when detecting a target moving in an "area extending directly behind the vehicle". When a target moves in such an area, at least a part of the target overlaps with the vehicle in the y-axis direction. Assuming that the target moves straight in the x-axis direction, when the target overlaps with the vehicle in part like this, the target is unlikely to pass by the side of the vehicle in the future. That is, the target is unlikely to become an obstruction target. On the other hand, when the target changes its traveling direction and passes by the side of the vehicle in the future (i.e., becomes an obstruction target), it is considered sufficient to execute the warning control at the time when the target changes its traveling direction (i.e., when it no longer overlaps with the vehicle). From the above, the inventors of the present application have set a specific condition by experiment and / or simulation based on the knowledge that if a target detected as an obstruction target moves in an area extending directly behind the vehicle, the target does not actually correspond to an obstruction target (in other words, there is a high possibility that the target is erroneously detected as an obstruction target due to an error in the calculation result of the moving direction of the target caused by the detection accuracy of the radar sensor 12). In this embodiment, the ECU 10 determines that the specific condition is satisfied when all of the following conditions a to c are satisfied.

[0041] (Condition a) At least a portion of the obstruction target is located within the rear vehicle width region Rvw of the host vehicle. (Condition b) The magnitude of change per unit time |Δy| of the y coordinate of the intersection point between the extension line of the velocity vector A of the obstruction target and the y axis is equal to or greater than a predetermined change threshold value Δyth. (Condition c) The x-axis component vx of the velocity of the obstruction object is greater than 0 and less than a predetermined velocity threshold vxth, and / or the x-axis component dx of the deceleration of the obstruction object is greater than or equal to a predetermined deceleration threshold dxth.

[0042] First, condition a will be described. As shown in FIG. 3, the rear vehicle width region Rvw of the host vehicle V is defined as a region between a virtual line L1 extending from a left rear corner of the host vehicle V in the -x-axis direction and a virtual line L2 extending from a right rear corner of the host vehicle V in the -x-axis direction. That is, the rear vehicle width region Rvw extends directly behind the host vehicle. Condition a is established when at least a part of the obstruction target is located within this rear vehicle width region Rvw (in other words, when the y coordinate closest to the x-axis among the y coordinates of the coordinate group constituting the obstruction target satisfies -w / 2≦y≦w / 2). According to experiments and / or simulations, when a target is erroneously detected as an obstruction target, the target tends to move in a region extending directly behind the host vehicle. For this reason, condition a was introduced.

[0043] Condition a may be configured to be satisfied when the y coordinate of the nearby portion np satisfies -w / 2≦y≦w / 2. Alternatively, condition a may be configured to be satisfied when the intrusion rate of the obstruction object into the rear vehicle width region Rvw is equal to or greater than a predetermined intrusion rate threshold. Here, the intrusion rate can be calculated by dividing the "length of the portion where the obstruction object overlaps with the host vehicle V in the y-axis direction" by the "vehicle width w of the host vehicle V."

[0044] Next, the condition b will be described. As described above, when a target is detected by the radar sensor 12, the ECU 10 calculates the y coordinate of the intersection between the extension line of the speed vector A of the target and the y axis based on the target information. Then, when the target is detected as an obstruction target, the ECU 10 calculates the magnitude of the change amount per unit time |Δy| of the y coordinate of the intersection (hereinafter, simply referred to as the "magnitude of the change amount |Δy|"). The condition b is established when the obstruction target satisfies |Δy|≧Δyth. According to experiments and / or simulations, when a target is erroneously detected as an obstruction target, the magnitude of the change amount |Δy| tends to be relatively large. This is considered to be because, when a target is erroneously detected as an obstruction target, an error occurs in the calculation result of the moving direction of the target due to the detection accuracy of the radar sensor 12, and the position of the intersection is likely to change (is unstable). For the above reasons, the condition b is introduced.

[0045] The change amount threshold Δyth is set to a value that makes it easy for |Δy|≧Δyth to be satisfied when the target is erroneously detected as an obstruction target, and makes it difficult for |Δy|≧Δyth to be satisfied when the moving direction of the target is accurately calculated. The unit time can be set to an appropriate value through experiments and / or simulations.

[0046] Next, condition c will be described. Condition c holds when the target satisfies 0 < vx < vxth and / or dx ≥ dxth. According to experiments and / or simulations, when a target is misdetected as an obstacle target, the target tends to move at a velocity v such that the velocity vx of the x-axis component is relatively small, and / or at a deceleration d such that the deceleration dx of the x-axis component is relatively large. For this reason, condition c was introduced. Note that the deceleration d is a value of 0 or more representing the degree of deceleration of the host vehicle, and increases as the braking force acting on the host vehicle increases. Note that the velocity threshold vxth is set to a value such that vx < vxth is likely to hold when the target is misdetected as an obstacle target, and vx < vxth is less likely to hold when the moving direction of the target is accurately calculated. Similarly, the deceleration threshold dxth is set to a value such that dx ≥ dxth is likely to hold when the target is misdetected as an obstacle target, and dx ≥ dxth is less likely to hold when the moving direction of the target is accurately calculated.

[0047] When all of conditions a to c are satisfied, the obstacle target (the target determined as such) is highly likely to be moving in the area extending behind the host vehicle. That is, the specific condition is a condition that is highly likely to hold when the obstacle target is moving in the area extending behind the host vehicle. When the specific condition holds, the ECU 10 determines that "the target determined as an obstacle target due to the satisfaction of condition 2" does not actually correspond to an obstacle target (that is, condition 2 holds only because an error has occurred in the calculation result of the moving direction of the target), and does not execute warning control. On the other hand, when the specific condition does not hold, the ECU 10 determines that the target is not moving in the area extending behind the host vehicle, or even if the target is moving in the area, it is only moving for the purpose of crossing the lane (own lane) in which the host vehicle is located (that is, it is determined that the target is highly likely to actually be an obstacle target), and executes warning control.

[0048] The effects of specific conditions will be described with reference to FIG. 3. FIG. 3 shows a situation where a passenger in the host vehicle V during parking attempts to open the right door and get out of the vehicle (i.e., under the condition where Condition 1 and Condition 3 are satisfied), and another vehicle Vt approaches the host vehicle V from behind while traveling straight in the +x-axis direction.

[0049] As shown in FIG. 3, the extension line of the velocity vector A of the other vehicle Vt does not actually intersect the intersection determination line L (i.e., the intersection point (point P) of the extension line and the y-axis is not located on the intersection determination line L). Therefore, at least at the current time, the other vehicle Vt does not correspond to an obstacle target. In other words, it is not necessary to execute warning control for the other vehicle Vt. However, in this example, due to the detection accuracy of the radar sensor 12, an error occurs in the calculation result of the moving direction of the other vehicle Vt. As a result, the ECU 10 erroneously calculates the intersection point of the extension line of the velocity vector A and the y-axis as point Pi (a point on the right intersection determination line LR) instead of point P. In this example, TTC≤TTCth is satisfied for the other vehicle Vt. Therefore, the other vehicle Vt is detected as an obstacle target (i.e., Condition 2 is satisfied).

[0050] As a result, since the warning condition is satisfied, the ECU 10 determines whether the specific condition is satisfied. In this example, the left side portion of the other vehicle Vt is located within the rear vehicle width region Rvw of the host vehicle V (Condition a). Also, due to the erroneous calculation of the intersection point as point Pi instead of point P, |Δy|≥Δyth is satisfied (Condition b). Furthermore, the other vehicle Vt is traveling at a relatively low speed so as not to collide with the host vehicle V, and 0<vx<vxth is satisfied (Condition c). Therefore, the ECU 10 determines that the specific condition is satisfied and does not execute warning control for the other vehicle Vt. That is, in the example of FIG. 3, even when the other vehicle Vt is detected as an obstacle target and the warning condition is thereby satisfied, when the specific condition is satisfied, the ECU 10 determines that it has been erroneously detected as an obstacle target due to an error in the calculation result of the moving direction of the other vehicle Vt, and does not execute warning control. According to this configuration, unnecessary operation of the warning control is suppressed.

[0051] In the example of Figure 3, the other vehicle Vt is traveling at a relatively slow speed, but instead, or in addition, the other vehicle Vt decelerates relatively significantly so as not to collide with the host vehicle V. As a result, even if dx≧dxth is satisfied, condition c is satisfied, and therefore the specific condition is satisfied.

[0052] In addition, since the specific condition includes condition b and / or condition c, even if condition a is satisfied (i.e., even if the obstruction object is located within the rear vehicle width region Rvw), if the obstruction object is merely moving within the rear vehicle width region Rvw with the purpose of crossing the vehicle's own lane, condition b and / or condition c (particularly condition c) are unlikely to be satisfied, and the specific condition is not satisfied, and as a result, ECU 10 executes warning control. According to this configuration, warning control is appropriately executed when the object actually corresponds to an obstruction object. In other words, the introduction of the specific condition makes it difficult for a situation to occur in which warning control is not executed even in a situation where the control is actually required.

[0053] The situation illustrated in FIG. 3 may typically occur in a country where driving on the left side is stipulated (a country where a lane layout is adopted in which the oncoming lane is located on the right side of the driving lane). In a country where driving on the right side is stipulated (a country where a lane layout is adopted in which the oncoming lane is located on the left side of the driving lane), a similar situation may occur when an occupant of the host vehicle V opens the left door to get off when the other vehicle Vt is moved symmetrically about the x-axis. However, in a country where driving on the left side is stipulated, a situation in which unnecessary activation of the alarm control occurs is not limited to when an occupant tries to get off from the right door, but may also occur when an occupant tries to get off from the left door (for example, when getting off in a parking lot). This is also true in a country where driving on the right side is stipulated.

[0054] According to the conventional disembarkation support device, when the alarm condition is satisfied, the alarm control is executed, and therefore, even if the target is not actually an obstruction target, if the target is erroneously detected as an obstruction target due to an error in the calculation result of the moving direction, the alarm control is executed, resulting in unnecessary operation. In contrast, according to the present embodiment, as illustrated in FIG. 3, when the alarm condition is satisfied, the alarm control is not executed immediately, but it is determined whether or not the specific condition is satisfied, and the alarm control is executed only when the specific condition is not satisfied. Therefore, when the alarm control is actually required, the control is executed appropriately, while unnecessary operation of the control is suppressed, and the reliability of the alarm control can be improved.

[0055] (Specific operation) Next, a description will be given of a specific operation of the ECU 10. The CPU of the ECU 10 is configured to repeatedly execute the routines shown in the flowcharts of Figures 4 to 6 in this order every time a predetermined time elapses while power is being supplied to the ECU 10 (described later).

[0056] 4, proceeds to step 410, and determines whether or not the host vehicle is in a stopped state based on the vehicle speed acquired from the vehicle speed sensor 11 (condition 1). If the host vehicle is in a traveling state, the CPU determines "No" in step 410 (i.e., determines that condition 1 is not satisfied (the warning condition is not satisfied)), proceeds to step 495, and temporarily ends this routine. On the other hand, if the host vehicle is in a stopped state, the CPU determines "Yes" in step 410 (i.e., determines that condition 1 is satisfied), and proceeds to step 420.

[0057] In step 420, the CPU determines whether or not a target has been detected based on the target information acquired from the radar sensor 12. If a target has not been detected, the CPU determines "No" in step 420, proceeds to step 495, and temporarily ends this routine. On the other hand, if a target has been detected, the CPU determines "Yes" in step 420, and proceeds to step 430.

[0058] In step 430, the CPU calculates the velocity vector A of the detected target based on the target information, and if an extension line of the velocity vector A intersects with either the left or right intersection determination line LL or LR, calculates the TTC for the target. Then, the CPU proceeds to step 440.

[0059] In step 440, the CPU judges whether or not TTC≦TTCth is satisfied for the detected target (condition 2). If TTC>TTCth, the CPU judges "No" in step 440 (i.e., judges that condition 2 is not satisfied (the warning condition is not satisfied)), proceeds to step 495, and temporarily ends this routine. On the other hand, if TTC≦TTCth, the CPU judges "Yes" in step 440 (i.e., judges that condition 2 is satisfied (the target is an obstruction target)), and proceeds to step 450.

[0060] In step 450, the CPU determines whether or not the door (the door on the side where the obstruction object is detected) is open based on the signal acquired from the door opening / closing sensor 13. If the door is closed, the CPU determines "No" in step 450 (i.e., determines that condition 3 is not satisfied (the alarm condition is not satisfied)), proceeds to step 495, and temporarily ends this routine. On the other hand, if the door is open, the CPU determines "Yes" in step 450 (i.e., determines that condition 3 is satisfied), proceeds to step 460, and determines that the alarm condition is satisfied. Thereafter, the CPU proceeds to step 495, and temporarily ends this routine.

[0061] When it is determined in step 460 that the alarm condition is satisfied, the CPU starts processing from step 500 in FIG. 5 and proceeds to step 510, and determines whether at least a part of the target (i.e., the inhibiting target) determined as "Yes" in step 440 of FIG. 4 is located within the rear vehicle width region Rvw (condition a). When the inhibiting target is not located within the rear vehicle width region Rvw, the CPU determines "No" in step 510 (i.e., determines that condition a is not satisfied (the specific condition is not satisfied)), proceeds to step 595, and temporarily ends this routine. On the other hand, when at least a part of the inhibiting target is located within the rear vehicle width region Rvw, the CPU determines "Yes" in step 510 (i.e., determines that condition a is satisfied), and proceeds to step 520.

[0062] In step 520, the CPU determines whether the inhibiting target satisfies |Δy|≧Δyth (condition b). When |Δy|<Δyth, the CPU determines "No" in step 520 (i.e., determines that condition b is not satisfied (the specific condition is not satisfied)), proceeds to step 595, and temporarily ends this routine. On the other hand, when |Δy|≧Δyth, the CPU determines "Yes" in step 520 (i.e., determines that condition b is satisfied), and proceeds to step 530.

[0063] In step 530, the CPU determines whether the inhibiting target satisfies 0<vx<vxth and / or dx≧dxth (condition c). When vx≧vxth and 0≦dx<dxth or ax≧0 (ax: the x-axis component of the acceleration of the inhibiting target), the CPU determines "No" in step 530 (i.e., determines that condition c is not satisfied (the specific condition is not satisfied)), proceeds to step 595, and temporarily ends this routine. On the other hand, when 0<vx<vxth and / or dx≧dxth, the CPU determines "Yes" in step 530 (i.e., determines that condition c is satisfied), proceeds to step 540, and determines that the specific condition is satisfied. Thereafter, the CPU proceeds to step 595 and temporarily ends this routine.

[0064] Thereafter, the CPU starts processing from step 600 in Fig. 6 and proceeds to step 610, where it determines whether or not the alarm condition is satisfied based on the determination result of the routine in Fig. 4. If the alarm condition is not satisfied (if the determination is "No" in any of steps 410, 420, 440, or 450), the CPU determines "No" in step 610, proceeds to step 695, and temporarily ends this routine. In other words, the CPU does not execute alarm control. On the other hand, if the alarm condition is satisfied (step 460), the CPU determines "Yes" in step 610, and proceeds to step 620.

[0065] In step 620, the CPU judges whether or not a specific condition is satisfied based on the judgment result of the routine in Fig. 5. If the specific condition is not satisfied (if the judgment is "No" in any of steps 510, 520, or 530), the CPU judges "No" in step 620 (i.e., judges that a situation requires alarm control) and proceeds to step 630. In step 630, the CPU transmits a drive command to the buzzer 20 to sound the buzzer 20. This executes alarm control. After that, the CPU proceeds to step 695 and temporarily ends this routine.

[0066] On the other hand, if the specific condition is satisfied (step 540), the CPU judges "Yes" in step 620 (i.e., judges that the alarm condition is satisfied only because an object that is not actually an obstruction object was erroneously detected as an obstruction object due to an error in the calculation result of its moving direction), and proceeds to step 695 to temporarily end this routine. That is, the CPU does not execute the alarm control. This makes it possible to appropriately execute the alarm control in a situation where the control is actually necessary, while suppressing unnecessary operation of the control, thereby improving the reliability of the alarm control. After that, the CPU proceeds to step 695 to temporarily end this routine.

[0067] The power supply to the ECU 10 continues until a predetermined condition is satisfied even after the ignition switch is turned off. For example, the condition may be satisfied when the doors are locked, or when a predetermined stop time has elapsed since the host vehicle stopped. With this configuration, it is possible to reduce the possibility that warning control will not be executed when it is necessary, and to more appropriately execute warning control.

[0068] Although the disembarking assistance device according to this embodiment has been described above, the present invention is not limited to the above embodiment, and various modifications are possible without departing from the object of the present invention.

[0069] For example, in the above embodiment, the specific condition is satisfied when all of the conditions a to c are satisfied, but the requirements for the specific condition are not limited to this. For example, the specific condition may be configured to be satisfied when the condition a is satisfied. When the warning condition is satisfied and at least a part of the obstruction target is located within the rear vehicle width region Rvw of the vehicle, the target is likely to be erroneously detected as an obstruction target due to an error in the calculation result of the moving direction. Therefore, even if the specific condition is configured to be satisfied when only the condition a is satisfied, unnecessary operation of the warning control can be suppressed. Alternatively, the specific condition may be configured to be satisfied when the conditions a and b are satisfied, or when the conditions a and c are satisfied.

[0070] In the above embodiment, the alarm control is executed as the dismounting assistance control, but the type of dismounting assistance control is not limited to this. For example, the door opening limit control that limits the degree of door opening or the door lock control that locks the door may be executed as the dismounting assistance control. Alternatively, in addition to the alarm control, the door opening limit control or the door lock control may be executed as the dismounting assistance control.

[0071] Furthermore, in the above embodiment, the process of sounding the buzzer 20 is executed as the warning control, but the contents of the warning control process are not limited to this. For example, the following processes, that is, a process of turning on a side mirror indicator (an indicator provided at a predetermined position on each of the left and right side mirrors of the vehicle) on the side where the obstruction target is detected, a process of displaying a predetermined mark (for example, a mark indicating whether the obstruction target is approaching from the left rear or the right rear) on the meter panel, and / or a process of uttering a predetermined message (for example, a message saying "Please be careful of approaching vehicles") from a speaker (a component of the navigation system), may be executed as the warning control instead of or in addition to the process of sounding the buzzer 20.

[0072] Furthermore, in the above embodiment, condition 2 is satisfied when TTC≦TTCth is satisfied for the target, but the requirement for satisfying condition 2 is not limited thereto. For example, condition 2 may be satisfied when TTC≦TTCth for the target continues for a predetermined duration. Condition 3 may be satisfied when the door on the side where the obstruction target is detected changes from a closed state to an open state. Alternatively, condition 3 may be satisfied when an occupant is detected operating a door operating part (typically an inner lever of the door) based on image data captured by a camera (a camera capable of capturing an image of an occupant inside the vehicle) installed in the vehicle.

[0073] In the above embodiment, the alarm condition is satisfied when all of conditions 1 to 3 are satisfied, but the requirements for satisfying the alarm condition are not limited to this. For example, the alarm condition does not have to include condition 3, and may be configured to be satisfied when conditions 1 and 2 are satisfied. In other words, the alarm control may be configured to be executed regardless of whether or not the occupant intends to get out of the vehicle.

[0074] Alternatively, the warning control may be executed in two stages. Specifically, the warning control includes two types of control, namely, normal warning control and mild warning control (control with a milder degree of assistance than the normal warning control). The mild warning control is, for example, a control that executes the above-mentioned side mirror indicator lighting process, and the normal warning control is, for example, a control that executes at least one of the above-mentioned "buzzer sounding process, mark display process on meter panel process, and speaker speech process" in addition to the side mirror indicator lighting process. The mild warning control is executed when Condition 1 and Condition 2 are satisfied (i.e., an obstruction target is detected while the vehicle is stopped, but the door is closed). The normal warning control is executed when Condition 3 is further satisfied in addition to Condition 1 and Condition 2 (i.e., an obstruction target is detected while the vehicle is stopped and the door is open). When the door is closed, it is not possible to determine whether the occupant is about to exit the vehicle through the door. In other words, there are two possibilities: the occupant has the intention to exit the vehicle but has not yet opened the door, and the occupant has no intention to exit the vehicle and the door will continue to be kept closed. Therefore, by executing the mild warning control when the door is closed, it is possible to simultaneously "notify the occupant who has the intention to exit the vehicle of the presence of an obstruction target in advance" and "prevent the occupant who has no intention to exit the vehicle from feeling inconvenience due to the execution of the normal warning control." When all of the conditions 1 to 3 are satisfied, the above-mentioned door opening restriction control or door lock control may be executed as the exit assistance control instead of the normal warning control. Alternatively, the door opening restriction control or door lock control may be executed as the exit assistance control in addition to the normal warning control.

[0075] Furthermore, in the above embodiment, the crossing judgment line L is introduced and an obstruction target is detected based on the TTC of the target, but the method of detecting the obstruction target is not limited to this. For example, a virtual area (more specifically, an area within the irradiation range of the radar sensor 12) having a predetermined size and shape may be set behind the vehicle (typically, on the left rear side and the right rear side), and when a target detected by the radar sensor 12 is located within the area, the target may be detected as an obstruction target. In this case, the shape of the area is not particularly limited and may be, for example, a trapezoid or a rectangle. [Explanation of symbols]

[0076] 10: Exit assistance ECU, 11: Vehicle speed sensor, 12: Radar sensor, 13: Door opening / closing sensor, 20: Buzzer

Claims

1. a target information acquisition device (12) that detects a target present behind the vehicle and acquires information about the detected target as target information; A control unit (10) capable of executing a vehicle exit assistance control for assisting a passenger in safely exiting the vehicle; In the disembarking assistance device, A portion of a front end of an obstacle object that may hinder the safe disembarking of the occupant while the vehicle is stopped that is closest to the host vehicle in a vehicle width direction of the host vehicle is defined as a proximate portion; If imaginary lines having a predetermined length that are positioned on a reference axis passing through the left and right rear corners of the vehicle and that extend from the left and right rear corners in a vehicle width outward direction are defined as intersection determination lines, The control unit When an intersection point between an extension line extending from the adjacent portion along the moving direction of the detected target and the reference axis is located on the intersection determination line, if a predicted time required for the target to reach the intersection point is equal to or less than a predetermined time threshold, the target is detected as an obstruction target and it is determined that an obstruction target has been detected; determining whether or not a dismounting assistance condition is satisfied when at least the obstruction object is detected; if the dismount assistance condition is satisfied, determine whether or not a specific condition is satisfied that is satisfied when at least a portion of the obstruction target is located within a rear vehicle width region that is a region between an imaginary line extending rearward in the fore-and-aft direction of the host vehicle from a left rear corner of the host vehicle and an imaginary line extending rearward from a right rear corner of the host vehicle, and the magnitude of the change in the position of the intersection per unit time is equal to or greater than a predetermined change threshold value; When the specific condition is not satisfied, the vehicle dismounting assistance control is executed. When the specific condition is satisfied, the vehicle dismount assistance control is not executed. It was configured as follows: Disembarkation assistance device.

2. The dismounting support device according to claim 1, The control unit (10) Furthermore, it is determined that the specific condition is satisfied when a component of the speed of the obstruction object in a forward / backward direction of the host vehicle is greater than 0 and less than a predetermined speed threshold, and / or when the component of the deceleration of the obstruction object in the forward / backward direction is equal to or greater than a predetermined deceleration threshold. It was configured as follows: Disembarkation assistance device.

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