Vehicle control device

Abstract

To provide a vehicular control device that can suppress an alarm from being unnecessarily actuated, by excluding a continuous obstacle except for a running road on which an own vehicle is running from collision objects.SOLUTION: The vehicular control device is provided with: a collision form predicting part 104 that when a collision determining part 103 determines that a vehicle is likely to collide with a target, predicts a collision form in which the vehicle collides with the target, on the basis of a relation between a travelling direction of the vehicle and a travelling direction of the target; and an actuation determining part that primarily determines a timing for actuating an alarm and an automatic brake for avoiding the vehicle from colliding with the target, in accordance with the predicted collision form by the collision form predicting part 104, and further secondarily determines whether or not the target is a continuous obstacle other than a running road on which the target continues in an arch-shape, on the basis of an index value obtained from a plurality of end point positions in geometrical information concerning the target, with respect to the primarily determined result.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a vehicle control device that can exclude consecutive obstacles outside the vehicle's traveling path from collision targets and suppress the activation of unnecessary alarms. [Background technology]

[0002] A technology has been developed that detects the speed and direction of movement of a vehicle and a target, predicts the possibility of a collision between the vehicle and the target based on the speed and direction of movement, and, if there is a possibility of a collision between the vehicle and the target, outputs a collision warning to alert the driver of the vehicle and activates automatic brakes.

[0003] Patent Document 1 discloses a system that, when it is predicted that there is a possibility of a collision between a vehicle and a target, determines whether the predicted collision position between the vehicle and the target is outside the driving path, and, if it is determined that the predicted collision position is outside the driving path, suppresses collision avoidance control to avoid a collision between the target and the vehicle. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent Publication No. 2021-124786 Summary of the Invention [Problem to be solved by the invention]

[0005] However, because the road is curved, obstacles that exist continuously along the roadside, such as guardrails and vehicles in adjacent lanes, cannot be distinguished as being in the path of the vehicle even when there is no risk of collision, resulting in unnecessary activation of a collision warning. For example, when approaching a right curve, the guardrail or vehicle in front of the vehicle is actually outside the path of the vehicle, but because it is directly in front of the vehicle's current direction of travel, the warning is unnecessary activated. This unnecessary warning annoys the driver and interferes with driving.

[0006] The present invention has been made in consideration of the above, and aims to provide a vehicle control device that can exclude consecutive obstacles outside the vehicle's driving path from collision targets and prevent unnecessary alarms from being activated. [Means for solving the problem]

[0007] In order to solve the above-mentioned problems and achieve the object, a vehicle control device according to the present invention is a vehicle control device comprising: a vehicle position prediction unit that predicts a vehicle future position, which indicates the position of a vehicle on which the vehicle control device is mounted after a predetermined time; a target position prediction unit that predicts a target future position, which indicates the position of a target after the predetermined time; a collision determination unit that determines whether or not there is a possibility of a collision between the vehicle and the target based on the vehicle future position and the target future position; a collision type prediction unit that, when it is determined that there is a possibility of a collision between the vehicle and the target, predicts a collision type between the vehicle and the target based on a relationship between a traveling direction of the vehicle and a traveling direction of the target; and an operation determination unit that makes a primary determination of the timing of issuing an alarm and activating an automatic brake to avoid a collision with the target in accordance with the collision type predicted by the collision type prediction unit, and further makes a secondary determination based on the primary determination result as to whether or not the target is a continuous obstacle outside a traveling lane that is continuous in an arc shape, based on index values ​​obtained from a plurality of end point positions of geometric information related to the target.

[0008] In addition, in the vehicle control device of the present invention, in the above invention, the index value is the distance between successive targets and the angle between the successive targets, and the operation judgment unit makes a secondary judgment that the successive targets are successive obstacles outside the driving path when the distance is less than a predetermined distance threshold and the angle is less than a predetermined angle.

[0009] In addition, in the vehicle control device of the present invention, in the above invention, the index value is a radius formed by successive targets and a vehicle speed of the vehicle, and the operation judgment unit makes a secondary judgment that the successive targets are successive obstacles outside the driving path when the radius is less than a predetermined radius threshold and the vehicle speed is less than a predetermined vehicle speed threshold.

[0010] In addition, in the vehicle control device of the present invention, in the above invention, the operation judgment unit makes a secondary judgment as to whether or not the consecutive obstacles are outside the driving path by hysteresis judgment using the index value, and makes a secondary judgment that the consecutive targets are consecutive obstacles outside the driving path on the condition that they are consecutive obstacles outside the driving path for a predetermined period of time, and makes a secondary judgment that the consecutive targets are not consecutive obstacles outside the driving path on the condition that they are not consecutive obstacles outside the driving path for the predetermined period of time.

[0011] In addition, in the vehicle control device according to the present invention, when it is determined that successive targets are successive obstacles outside the travel path, the operation determination unit increases the upper and lower thresholds of the hysteresis determination for the next and subsequent successive targets, thereby making the determination of successive obstacles outside the travel path more lenient.

[0012] In addition, in the above invention, the vehicle control device of the present invention includes an execution unit that, when the activation determination unit makes a secondary determination that the target is a continuous obstacle outside the driving path, delays the activation timing of the alarm that was primarily determined by the activation determination unit and executes it at the time when a collision between the vehicle and the target is predicted. [Effects of the Invention]

[0013] According to the present invention, it is possible to exclude consecutive obstacles outside the traveling path of the vehicle from collision targets, thereby preventing unnecessary activation of an alarm. [Brief explanation of the drawings]

[0014] [Figure 1] FIG. 1 is a block diagram showing the configuration of a vehicle control device according to this embodiment. [Figure 2]FIG. 2 is a functional block diagram showing the internal configuration of the vehicle control device. [Figure 3] FIG. 3 is a flowchart showing a vehicle control processing procedure performed by the vehicle control device. [Figure 4] FIG. 4 is an explanatory diagram showing an example of a process for predicting a collision type and a process for calculating an automatic braking timing of a vehicle. [Figure 5] FIG. 5 is an explanatory diagram showing an example of a control process for automatic braking of a vehicle in a vehicle control device. [Figure 6] FIG. 6 is a time chart showing an example of the timing of warning and automatic braking. [Figure 7] FIG. 7 is a diagram showing an example of a series of obstacles outside a travel path, in which targets are successively arranged in an arc shape. [Figure 8] FIG. 8 is an explanatory diagram for explaining calculation of distance and angle, which are index values ​​used in the secondary determination process by the operation determination unit. [Figure 9] FIG. 9 is a detailed flowchart showing the procedure of the secondary determination process. [Figure 10] FIG. 10 is an explanatory diagram illustrating the hysteresis control shown in FIG. [Figure 11] FIG. 11 is an explanatory diagram for explaining calculation of the radius, which is an index value used in the secondary determination process by the operation determination unit. DETAILED DESCRIPTION OF THE INVENTION

[0015] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A vehicle control device according to an embodiment of the present invention will be described in detail below with reference to the accompanying drawings.

[0016] <Overall structure> FIG. 1 is a block diagram showing the configuration of a vehicle control device 1 according to this embodiment. The vehicle control device 1 is a device that is mounted on a vehicle X (see FIG. 4) and assists in driving the vehicle X. Here, the vehicle X may be, for example, an electric vehicle, a hybrid vehicle, or an autonomous vehicle. The vehicle control device 1 has a driving assistance function for avoiding a collision between the vehicle X and a target T (see FIG. 4) or for reducing damage caused by the collision. Here, the target T is an object such as a vehicle, a person, or an obstacle ahead. The driving assistance function also includes a collision warning function, a primary braking function, and a secondary braking function.

[0017] The collision warning function warns of the possibility of a collision before the automatic brake is activated. The primary braking function is a function (gentle braking function) that uses the automatic brake to decelerate vehicle X at a primary target deceleration in order to prompt the driver to take action to avoid the collision. The secondary braking function is a function (hard braking function) that uses the automatic brake to decelerate vehicle X at a secondary target deceleration that is greater than the primary target deceleration in order to avoid the collision and reduce the damage caused by the collision (see Figure 6).

[0018] The vehicle control device 1 includes an ECU (Electronic Control Unit) 11. The ECU 11 is equipped with a microcontroller 12. The microcontroller 12 has a built-in CPU 13 and memory 14. In addition to the ECU 11, the vehicle X is equipped with a plurality of ECUs for controlling various parts. The ECU 11 is connected to other ECUs so as to be able to perform two-way communication using a CAN (Controller Area Network) communication protocol.

[0019] The vehicle X is also equipped with a camera 21. The camera 21 is, for example, a stereo camera capable of continuously capturing still images at a predetermined frame rate, and is installed, for example, in front of the rearview mirror at the center of the front of the vehicle interior so as to be able to capture images of the area ahead of the vehicle X at a wide angle. The camera 21 extracts target pixels corresponding to the same target object in each image captured by the image sensors from a pair of image data input from the image sensors of both the left and right eyes. Next, the camera 21 detects the amount of deviation in the position of the target pixel between the pair of images, and calculates the distance to the same target object (target T) using the principle of triangulation. An output signal from the camera 21 is input to the ECU 11.

[0020] The vehicle X is further provided with a vehicle speed sensor 22, a steering angle sensor 23, and a yaw rate sensor 24. The vehicle speed sensor 22 outputs, as a detection signal, a pulse signal synchronized with the rotation of a rotating body (e.g., a drive shaft) that rotates as the vehicle X travels. The steering angle sensor 23 outputs a detection signal corresponding to the steering angle (absolute steering angle) of the steering mechanism (e.g., a steering wheel) of the vehicle X relative to the steering angle midpoint. The steering angle takes a positive value when the steering mechanism is turned to the right (the steering wheel is turned to the right) from the steering angle midpoint, and takes a negative value when it is turned to the left (the steering wheel is turned to the left).

[0021] The yaw rate sensor 24 outputs a detection signal corresponding to the yaw rate, which is the rotational angular velocity around a vertical axis passing through the center of gravity of the vehicle X. The detection signals of the vehicle speed sensor 22, the steering angle sensor 23, and the yaw rate sensor 24 are input to the ECU 11.

[0022] Vehicle X is equipped with a hydraulic brake system. The brake system includes a brake pedal, a brake booster, a master cylinder, a brake actuator 25, and brakes provided on each wheel. The brake pedal is located in a position that is convenient for the driver sitting in the driver's seat to operate it with his / her right foot. When the brake pedal is depressed, the force input to the brake pedal is transmitted to the brake booster. The brake booster utilizes the negative pressure generated in the engine's intake system, and the pressure difference between this negative pressure and atmospheric pressure amplifies the force applied to the brake pedal.

[0023] The force amplified by the brake booster is transmitted from the brake booster to the master cylinder, which generates hydraulic pressure corresponding to that force. The hydraulic pressure from the master cylinder is transmitted to brake actuator 25, which supplies hydraulic pressure to the wheel cylinders of the brakes provided on each wheel, causing each brake to apply braking force to the wheel. Brake actuator 25 also contains an electric pump, which is driven by power from the battery when the automatic brake is activated, and hydraulic pressure generated by the electric pump is supplied to each wheel cylinder.

[0024] The vehicle X is also provided with an alarm 26. The alarm 26 outputs various types of alarms, and the alarms may be output by light, sound, or voice.

[0025] <Internal function configuration> Fig. 2 is a functional block diagram showing the internal configuration of the vehicle control device 1. In the vehicle control device 1, the CPU 13 executes various programs stored in the memory 14 to realize various functional units such as a vehicle position prediction unit 101, a target position prediction unit 102, a collision determination unit 103, a collision type prediction unit 104, an operation determination unit 105, and an execution unit 106, as shown in Fig. 2. In the vehicle control device 1 according to this embodiment, the CPU 13 executes various programs stored in the memory 14 to realize various functional units such as the vehicle position prediction unit 101, the target position prediction unit 102, the collision determination unit 103, the collision type prediction unit 104, the operation determination unit 105, and the execution unit 106, but this is not limiting, and each functional unit can also be realized by hardware.

[0026] The vehicle position prediction unit 101 predicts a future position indicating the position of the vehicle X after a predetermined time (hereinafter referred to as the vehicle future position). Here, the predetermined time is a time set in advance. In this embodiment, the vehicle position prediction unit 101 predicts the vehicle future position based on the vehicle speed corresponding to the detection signal output from the vehicle speed sensor 22, the steering angle corresponding to the detection signal output from the steering angle sensor 23, the rotational angular velocity corresponding to the detection signal output from the yaw rate sensor 24, etc. Also, in this embodiment, the vehicle position prediction unit 101 predicts the vehicle future position at each minute time from the current time until a predetermined time has elapsed.

[0027] The target position prediction unit 102 predicts a future position indicating the position of the target T after a predetermined time (hereinafter referred to as the target future position). In this embodiment, the target position prediction unit 102 predicts the target future position based on the distance to the target T calculated by the camera 21. That is, the target position prediction unit 102 predicts the target future position based on captured image data. In this embodiment, the target position prediction unit 102 predicts the target future position at each short time from the current time until a predetermined time later.

[0028] The collision determination unit 103 determines whether or not there is a possibility of collision between the vehicle X and the target T, based on the vehicle future position and the target future position. In this embodiment, the collision determination unit 103 sets a rectangular vehicle area surrounding the vehicle X located at the vehicle future position. If the target future position is included in the set vehicle area, the collision determination unit 103 determines that there is a possibility of collision between the vehicle X and the target T. Furthermore, in this embodiment, the collision determination unit 103 determines whether or not there is a possibility of collision between the vehicle X and the target T, based on the vehicle future position and the target future position, at each short time interval from the current time until a predetermined time has elapsed.

[0029] When it is determined that there is a possibility of a collision between the vehicle X and the target T, the collision type prediction unit 104 predicts a collision type between the vehicle X and the target T based on the relationship between the traveling direction of the vehicle X and the traveling direction of the target T. In this embodiment, the collision type prediction unit 104 also functions as an example of an area setting unit that sets a vehicle area surrounding the periphery of the future vehicle position of the vehicle X and a target area surrounding the future target position of the target T. Next, the collision type prediction unit 104 predicts a collision type (e.g., a full-overlap frontal collision, an offset frontal collision, or a side collision) including a collision portion of the target T on the vehicle X based on the set vehicle area and target area and the angle θ. This enables control processing of the vehicle X based on the collision portion of the target T with respect to the vehicle X, making it possible to deal with a wider variety of collision types between the vehicle X and the target T.

[0030] Here, the angle θ (see FIG. 4) is the angle between the traveling direction of the vehicle X and the traveling direction of the target T. In this embodiment, the collision type prediction unit 104 sets a vehicle area and a target area, but it is sufficient if it predicts a collision type based on an area surrounding at least one of the vehicle future position and the target future position.

[0031] In this embodiment, the collision types include a rear-end collision type and a cross-sectional collision type. Here, the rear-end collision type is a collision type (rear-end collision type) in which one of the vehicle X and the target T collides with the other without entering the path of the other. In other words, the rear-end collision type is a collision type in which the front of one of the vehicle X and the target T collides with the other. Furthermore, the cross-sectional collision type is a collision type other than a rear-end collision, in which one of the vehicle X and the target T enters the path of the other and collides. In other words, the cross-sectional collision type is a collision type in which the front of one of the target T and the vehicle X collides with the side of the other. This cross-sectional collision type also includes a head-on collision with an angle θ of 180 degrees.

[0032] The operation determination unit 105 makes a primary determination of the timing to issue an alarm and activate an automatic brake to avoid a collision with the target object, according to the collision type predicted by the collision type prediction unit 104, and then makes a secondary determination of whether the target objects are consecutive arc-shaped obstacles outside the driving path based on an index value obtained from multiple endpoint positions of geometric information related to the target objects. The index value is the distance between consecutive targets and the angle between the consecutive targets, and the operation determination unit 105 makes a secondary determination that the consecutive targets are consecutive obstacles outside the driving path if the distance is less than a predetermined distance threshold and the angle is less than a predetermined angle.

[0033] When the activation determination unit 105 makes a secondary determination that the target is a continuous obstacle outside the driving range, the execution unit 106 delays the activation timing of the alarm primarily determined by the activation determination unit at the time when a collision between the vehicle and the target is predicted. Note that when the activation determination unit 105 makes a secondary determination that the target is not a continuous obstacle outside the driving range, the execution unit 106 executes the alarm or the activation of an alarm and automatic brake (predetermined control) primarily determined by the activation determination unit at the time when a collision between the vehicle and the target is predicted.

[0034] Here, the predetermined control is a control that is set in advance, such as the timing (hereinafter referred to as the activation timing) of activating an automatic brake (so-called AEB: Autonomous Emergency Braking) or changing the type of warning to the driver. Here, the automatic brake is a brake that suppresses a collision between the vehicle X and the target T. In other words, the predetermined control is a control that avoids a collision between the vehicle X and the target T.

[0035] In this embodiment, the execution unit 106 executes a predetermined control on the vehicle X based on the collision location predicted by the collision type prediction unit 104, in accordance with the primary determination result of the operation determination unit 105. However, if the secondary determination result of the operation determination unit 105 indicates that the target is a continuous obstacle outside the vehicle, the timing of issuing an alarm is delayed, thereby preventing unnecessary alarms from being issued and not affecting the driver's driving.

[0036] Specifically, the predetermined control by the execution unit 106 changes the timing of activation of the automatic brake depending on whether the collision type is a rear-end collision type or a crossing collision type predicted by the collision type prediction unit 104. More specifically, the execution unit 106 changes the timing of activation of the automatic brake depending on the collision position due to the rear-end collision type and the collision position due to the crossing collision type. For example, when the predicted collision type is a rear-end collision type, the execution unit 106 activates the automatic brake so that the vehicle X stops before the collision position between the vehicle X and the target T according to the time to collision (TTC). In other words, the execution unit 106 activates the automatic brake from a position away from the collision position between the vehicle X and the target T, in the opposite direction to the traveling direction of the vehicle X, by the braking distance of the automatic brake.

[0037] On the other hand, if the predicted collision type is a cross-sectional collision type, the execution unit 106 activates the automatic brakes in accordance with the time to collision so that the vehicle X stops before the collision position between the vehicle X and the target T. Alternatively, the execution unit 106 activates the automatic brakes in accordance with the time to brake (TTB) so that the vehicle X stops before the collision position between the vehicle X and the target T and before the path of the target T. In other words, the execution unit 106 activates the automatic brakes from a position just before the path of the target T, in the opposite direction to the traveling direction of the vehicle X, at a distance equal to the braking distance of the automatic brakes. This makes it possible to activate the automatic brakes at appropriate timing for both a rear-end collision type and a cross-sectional collision type.

[0038] <Vehicle control processing> 3 is a flowchart showing a vehicle control processing procedure performed by the vehicle control device 1. As shown in FIG. 3, first, the target position prediction unit 102 calculates the target position, which is the position of the target T, based on image data captured by the camera 21, and the vehicle position prediction unit 101 acquires traveling information (step S11). Here, the target position is the position of the target T relative to the center position of the vehicle X. In addition, the traveling information includes the vehicle speed, steering angle, rotational angular velocity, etc. of the vehicle X.

[0039] Thereafter, the target position prediction unit 102 predicts a target future position indicating the position of the target T after a predetermined time based on the calculated target position, and the vehicle position prediction unit 101 predicts a vehicle future position indicating the position of the vehicle X after a predetermined time based on the acquired traveling information (step S12).

[0040] Thereafter, the collision determination unit 103 determines whether or not there is a possibility of a collision between the vehicle X and the target T based on the vehicle future position and the target future position (step S13). If the collision determination unit 103 determines that there is no possibility of a collision between the vehicle X and the target T (step S13: No), this process ends. On the other hand, if the collision determination unit 103 determines that there is a possibility of a collision between the vehicle X and the target T (step S13: Yes), the collision type prediction unit 104 predicts a collision type between the vehicle X and the target T based on the relationship between the traveling direction of the vehicle X and the traveling direction of the target T (step S14).

[0041] Thereafter, the operation determination unit 105 performs a primary determination process to determine the timing of issuing an alarm and activating an automatic brake to avoid a collision with the target T, in accordance with the collision type predicted by the collision type prediction unit 104 (step S15). Furthermore, the operation determination unit 105 performs a secondary determination process to determine whether the target is a continuous arc-shaped obstacle outside the driving lane (step S16).

[0042] Thereafter, the secondary determination process determines whether or not the target is determined to be a continuous obstacle outside the driving path (step S17). If it is determined to be a continuous obstacle outside the driving path (step S17: Yes), the execution unit 106 executes collision avoidance control to delay the warning timing of the primary determination result (step S18), and ends this process. On the other hand, if it is not determined to be a continuous obstacle outside the driving path (step S17: No), the execution unit 106 executes collision avoidance control at the warning and automatic brake activation timing of the primary determination result (step S19), and ends this process. Note that this process is repeated at predetermined time intervals.

[0043] <Specific collision avoidance control> 4 is an explanatory diagram showing an example of a process for predicting a collision type and a process for calculating the activation timing of an automatic brake of the vehicle X. First, when the collision determination unit 103 determines that there is a possibility of a collision between the vehicle X and the target T, the collision type prediction unit 104 calculates the angle θ formed between a vehicle traveling direction vector Vvec, which is a vector representing the traveling direction of the vehicle X, and a target traveling direction vector Gvec, which is a vector representing the traveling direction of the target T. In other words, the angle θ is the angle formed between the traveling direction of the vehicle X and the traveling direction of the target T.

[0044] Specifically, the collision mode prediction unit 104 calculates the vehicle traveling direction vector Vvec based on the current position VUT(t-1) of the vehicle X at the current time t-1 and the future position VUT(t) of the vehicle X at a future time t that is a predetermined time after the current time, as shown in the following equation (1). Vvec=VUT(t)-VUT(t-1) (1)

[0045] In addition, the collision type prediction unit 104 calculates the target traveling direction vector Gvec based on the current position GVT(t-1) of the target T at the current time t-1 and the target future position GVT(t) of the target T at the future time t, as shown in the following equation (2). Gvec = GVT(t) - GVT(t-1) (2)

[0046] Then, the collision type prediction unit 104 calculates the angle θ formed by the vehicle traveling direction vector Vvec and the target traveling direction vector Gvec, as shown in the following equation (3). cosθ=Vvec·Gvec / |Vvec||Gvec|···(3)

[0047] Furthermore, the collision type prediction unit 104 determines whether the angle θ is smaller than a threshold value θt (for example, 10 degrees). Here, the threshold value (an example of a predetermined threshold value) θt is, for example, 10 degrees, which is the threshold value of the angle θ at which it is determined that the vehicle traveling direction vector Vvec and the target traveling direction vector Gvec are substantially the same and that the vehicle X and the target T will collide in a collision type other than a rear-end collision.

[0048] If the angle θ is smaller than the threshold value θt, the collision type prediction unit 104 predicts that the collision type between the vehicle X and the target T will be a rear-end collision type. Next, the collision type prediction unit 104 determines whether or not an end point of the vehicle X in the traveling direction is within the target area of ​​the target T. In this embodiment, as shown in FIG. 4, if the vehicle area of ​​the vehicle X is a rectangular area, the collision type prediction unit 104 sets corners A, B, C, and D of the rectangular area based on the center position OX of the vehicle X as the end points of the vehicle area. Also, as shown in FIG. 4, if the target area of ​​the target T is a rectangular area, the collision type prediction unit 104 sets corners E, F, G, and H of the rectangular area based on the center position OT of the target T as the end points of the target area.

[0049] Then, the collision type prediction unit 104 determines whether or not the end points A, B, C, and D of the vehicle area at future time t are within a target area based on the center position OT of the target T at future time t. For example, the collision type prediction unit 104 calculates the cross products of EF×EA, FG×FA, GH×GA, and HE×HA, and determines that the end point A is within the target area if the signs of the calculated cross products match. The collision type prediction unit 104 can similarly determine whether or not the end points B, C, and D of the vehicle area are within the target area.

[0050] When an end point on the traveling direction side of the vehicle X (for example, at least one of the end points A and B shown in FIG. 4) is within the target area of ​​the target T, the collision type prediction unit 104 predicts that the collision type between the vehicle X and the target T is a rear-end collision type in which the front surface (front part) of the vehicle X collides with the rear surface (rear part) of the target T.

[0051] In this case, the operation determination unit 105 performs a primary determination to calculate the timing to operate the automatic brake so that the vehicle X stops before the collision position where the vehicle X collides with the target T, according to the time to collision (TTC).

[0052] On the other hand, if the end point in the traveling direction of vehicle X is not within the target area of ​​target T, the collision type prediction unit 104 predicts that the collision type between vehicle X and target T is a rear-end collision type in which the front surface (front part) of target T collides with the rear surface (rear part) of vehicle X. In this case, the operation determination unit 105 performs a primary determination to notify the driver of vehicle X that target T will collide with vehicle X from the rear without executing predetermined control, or to allow vehicle X to continue traveling as is by issuing a warning (an example of predetermined control) to the driver of vehicle X.

[0053] That is, it is difficult to determine whether the vehicle X will collide with the target T from the angle θ between the vehicle traveling direction vector Vvec and the target traveling direction vector Gvec alone, or whether the vehicle X will not be hit from the rear by the target T. In the case of a non-collision, there is little need to activate the automatic brake of the vehicle X, so it is necessary to determine which part of the vehicle X the target T will collide with.

[0054] For this reason, the collision type prediction unit 104 predicts whether the collision type between vehicle X and target T will be a collision type in which the front of vehicle X collides with target T by determining whether at least one of the endpoints in the traveling direction of vehicle X is within the target area of ​​target T. That is, if the angle θ is smaller than the threshold value θt and the endpoint in the traveling direction of vehicle X is within the target area, the collision type prediction unit 104 predicts that the collision type between vehicle X and target T will be a collision type in which the front of vehicle X collides with the rear of a preceding vehicle, which is an example of target T. On the other hand, if the angle θ is smaller than the threshold value θt and the endpoint in the traveling direction of vehicle X is not within the target area, the collision type prediction unit 104 predicts that the collision type between vehicle X and target T will be a collision type in which the front of target T collides with the rear of vehicle X.

[0055] Furthermore, if the angle θ is equal to or greater than the threshold value θt, the collision type prediction unit 104 predicts that the collision type between the vehicle X and the target T will be a crossing collision type (a collision type other than a rear-end collision type). Next, the collision type prediction unit 104 determines whether or not the end point of the vehicle X in its traveling direction is within the target area of ​​the target T. The collision type prediction unit 104 determines whether or not the end point of the vehicle X in its traveling direction is within the target area of ​​the target T.

[0056] When the end point of the vehicle X in the traveling direction is within the target area of ​​the target T, the collision type prediction unit 104 predicts that the collision type between the vehicle X and the target T is a cross-sectional collision type (side impact) in which the front (front part) of the vehicle X collides with the side (side part) of the target T. In this case, the operation determination unit 105 performs a primary determination to calculate the operation timing of the automatic brake so that the vehicle X stops before the collision position between the vehicle X and the target T according to the time to collision (TTC).

[0057] On the other hand, if the end point in the traveling direction of vehicle X is not within the target area of ​​target T, the collision type prediction unit 104 determines whether the end point of target T is within the vehicle area of ​​vehicle X. The collision type prediction unit 104 determines whether end points E, F, G, and H of the target area of ​​target T at future time t are within a vehicle area based on the center position OX of vehicle X at future time t. For example, the collision type prediction unit 104 calculates the cross products of AB×AE, BC×BE, CD×CE, and DA×DE, and if the signs of the calculated cross products match, determines that end point E is within the vehicle area. The collision type prediction unit 104 similarly determines whether end points F, G, and H of target T are within the vehicle area.

[0058] When the end point of the target T in the traveling direction, i.e., at least one of the end points E and F shown in Fig. 4, is not within the vehicle area of ​​the vehicle X, the collision type prediction unit 104 determines that the vehicle X will not collide with the target T. On the other hand, when the end point of the target T in the traveling direction, i.e., at least one of the end points E and F shown in Fig. 4, is within the vehicle area of ​​the vehicle X, the collision type prediction unit 104 predicts that the collision type between the vehicle X and the target T will be a cross-sectional collision type (side impact) in which the front (front part) of the target T collides with the side (side part) of the vehicle X.

[0059] In this case, the operation determination unit 105 performs a primary determination to calculate the timing of automatic braking so that the vehicle X stops before the path of the target T according to the time to brake (TTB).

[0060] Even when one of vehicle X and target T crosses the other's path, the timing at which the automatic brake needs to be activated differs depending on whether the collision type is one in which the front of vehicle X collides with target T or one in which the front of target T collides with the side of vehicle X. For example, if the collision type between vehicle X and target T is one in which target T collides with the side of vehicle X, there is a possibility that vehicle X may be able to pass through target T by operating the vehicle driver, and the timing at which the automatic brake needs to be activated must be calculated while respecting the driver's intentions.

[0061] For this reason, the collision type prediction unit 104 determines whether or not the end points E and F of the target T in the traveling direction are within the vehicle area, thereby predicting whether or not the collision type between the vehicle X and the target T will be a collision type in which the front of the target T collides with the side of the vehicle X. That is, if the angle θ is equal to or greater than the threshold value θt and the end point of the vehicle X in the traveling direction is within the target area, the collision type prediction unit 104 predicts that the collision type between the vehicle X and the target T will be a collision type in which the front of the vehicle X collides with the side of the target T. On the other hand, if the angle θ is equal to or greater than the threshold value θt, the end point of the vehicle X in the traveling direction is not within the target area, and the end point of the target T in the traveling direction is within the vehicle area, the collision type prediction unit 104 predicts that the collision type between the vehicle X and the target T will be a collision type in which the front of the target T collides with the side of the vehicle X. When the angle θ is 180 degrees, the collision type prediction unit 104 determines that the collision type between the vehicle X and the target T is a head-on collision.

[0062] FIG. 5 is an explanatory diagram showing an example of a control process for the automatic braking of a vehicle in a vehicle control device 1. In a conventional vehicle control device, when calculating the timing for applying the automatic brake of vehicle X, regardless of the type of collision between vehicle X and another vehicle Y, which is an example of a target T, the timing for applying the automatic brake is calculated to be a distance d2 before the stopping position P2 so that vehicle X stops at a stopping position P2 that is a distance d1 before the collision position P1 between vehicle X and another vehicle Y in the traveling direction of vehicle X. Here, distance d2 is the braking distance of the automatic brake. Therefore, when vehicle X enters the path of another vehicle Y and the front of the other vehicle Y collides with the side of vehicle X, the conventional vehicle control device stops vehicle X at the stopping position P2 in the path of the other vehicle Y, as shown in FIG. 5(a), which may result in the front of the other vehicle Y colliding with the side of vehicle X.

[0063] In contrast, in the vehicle control device 1, when vehicle X enters the path of another vehicle Y and the front of the other vehicle Y collides with the side of vehicle X, the operation determination unit 105 performs a primary determination to calculate the timing for automatic braking to occur a distance d2 before the stopping position P3 so that vehicle X will stop at stopping position P3 just before the path of the other vehicle Y, as shown in FIG. 5(b). As a result, when it is determined that there is a possibility that the front of the other vehicle Y will collide with the side of vehicle X, vehicle X can be stopped without entering the path of the other vehicle Y. As a result, even if the front of the other vehicle Y collides with the side of vehicle X, it is possible to avoid a collision between vehicle X and other vehicle Y.

[0064] In this way, according to the vehicle control device 1, when it is determined that there is a possibility of a collision between the vehicle X and the target T, the type of collision between the vehicle X and the target T is predicted based on the relationship between the traveling direction of the vehicle X and the traveling direction of the target T, and predetermined control (normal control) is executed on the vehicle X in accordance with the predicted type of collision. This makes it possible to change the control on the vehicle X in accordance with the type of collision between the vehicle X and the target T, and therefore makes it possible to deal with a wide variety of types of collision between the vehicle X and the target T.

[0065] FIG. 6 is a time chart showing an example of the timing of warning and automatic braking activation. As shown in FIG. 6, if a possibility of collision is predicted at the current time t0, a warning is issued at time t1, which is a time T1 back from time t10 when the vehicle stops, corresponding to the time to collision (TTC). Furthermore, the primary brake is activated at time t2, which is a time (T2+T3) back from time t10 corresponding to the time to brake (TTB), and the secondary brake, which is stronger than the primary brake, is activated at time t3. The primary and secondary brakes are integrated, and the automatic brake is activated from time t2. Note that the secondary brake can be further changed to maximum braking as time passes depending on the stopping position.

[0066] Here, in this embodiment, the operation determination unit 105 makes a secondary determination as to whether or not the target is a continuous obstacle outside the driving path that is continuous in an arc, and if the result of this secondary determination is that the target is not a continuous obstacle outside the driving path, the operation determination unit 105 executes the above control content that was primarily determined by the operation determination unit 105, and if the result of this secondary determination is that the target is a continuous obstacle outside the driving path, the operation determination unit 105 executes control to delay the alarm notification device of the above control content that was primarily determined by the operation determination unit 105.

[0067] <Example of a continuous obstacle outside the travel path> Fig. 7 is a diagram showing an example of a continuous obstacle outside the travel lane, where the target objects are continuous in an arc. Fig. 7(a) shows an example where a vehicle X approaches a right curve along a travel lane BR and there are a series of roadside objects, guardrails Z, visible in front of the vehicle. In this case, the guardrails Z are currently in front of the vehicle X in the traveling direction, so a collision is predicted at a collision prediction point P10. However, in reality, the guardrails Z are outside the travel lane of the vehicle X, so no collision occurs.

[0068] On the other hand, Figure 7(b) shows an example in which vehicle X approaches a right curve along roadway BR, and the convoy of vehicle Y visible in front of it continues in the adjacent lane on the side of the road. In this case, since vehicle Y's convoy is directly in front of vehicle X in the direction of travel, a collision is predicted at collision prediction point P10. However, in reality, vehicle X is outside the roadway of vehicle X, so no collision occurs. In both cases of Figure 7(a) and Figure 7(b), vehicle X continues traveling along roadway BR with the alarm still activated.

[0069] <Calculation of index value> 8 is an explanatory diagram for explaining calculation of the distance D and angle θ, which are index values ​​used in the secondary determination process by the operation determination unit 105. Fig. 8(a) shows a case where vehicles Y1 and Y2, which are targets, are in a line of vehicles in adjacent lanes, and the operation determination unit 105 can obtain the end points A, B, C, and D and the center position P1 of vehicle Y1, and the end points E, F, G, and H and the center position P2 of vehicle Y2, in the same way as in Fig. 4, by capturing images of vehicles Y1 and Y2.

[0070] The distance D between consecutive targets and the angle θ between consecutive targets shown in Figure 8(b) are index values ​​that can be found using the endpoint positions of vehicles Y1 and Y2. First, the angle θ can be obtained by obtaining vectors DA and HE from the endpoint differentials. The angle θ can be found using the dot product of these vectors as shown in the following equation (4). cosθ=DA·HE / |DA||HE|···(4)

[0071] Furthermore, the distance D can be calculated as the distance between the center positions P1 and P2 by the following equation (5). D=√((P1 x -P2 x ) 2 +(P1 y -P2 y ) 2 ) ···(5) In addition, P1 x and P1 y indicate the x and y components of P1(x, y), respectively. x and P2 y indicate the x and y components of P2(x, y), respectively.

[0072] <Secondary judgment process> 9 is a detailed flowchart showing the procedure of the secondary determination process in step S16. As shown in FIG. 9, the operation determination unit 105 first acquires position information of targets (step S21). Then, the angle θ between successive targets and the distance D between the targets are calculated (step S22).

[0073] Thereafter, it is determined whether the angle θ is less than the lower limit angle θin and the distance D is less than the lower limit distance Din (step S23). If the angle θ is less than the lower limit angle θin and the distance D is less than the lower limit distance Din (step S23: Yes), it is further determined whether the state in which the angle θ is less than the upper limit angle θout and the distance D is less than the upper limit distance Dout has continued for a predetermined period (step S24). If the state in which the angle θ is less than the upper limit angle θout and the distance D is less than the upper limit distance Dout has continued for a predetermined period (step S24: Yes), it is determined that the target is a continuous obstacle outside the traveling path (step S25), and the process returns to step S16. On the other hand, if the state in which the angle θ is less than the upper limit angle θout and the distance D is less than the upper limit distance Dout has not continued for a predetermined period (step S24: No), the process returns directly to step S16.

[0074] On the other hand, if the angle θ is less than the lower limit angle θin and the distance D is not less than the lower limit distance Din (step S23: No), it is further determined whether the angle θ exceeds the upper limit angle θout and the distance D exceeds the upper limit distance Dout (step S26).If the angle θ exceeds the upper limit angle θout and the distance D exceeds the upper limit distance Dout (step S26: Yes), it is further determined whether the state in which the angle θ exceeds the lower limit angle θin and the distance D exceeds the lower limit distance Din has continued for a predetermined period (step S27).

[0075] If the state in which the angle θ exceeds the lower limit angle θin and the distance D exceeds the lower limit distance Din continues for a predetermined period (step S27: Yes), the determination that the target is a continuous obstacle outside the traveling path is canceled (step S28), and the process returns to step S16. On the other hand, if the state in which the angle θ exceeds the lower limit angle θin and the distance D exceeds the lower limit distance Din does not continue for a predetermined period (step S27: No), the process returns directly to step S16.

[0076] In the secondary determination process shown in FIG. 9, hysteresis control is performed using the lower limit angle θin, the upper limit angle θout, the lower limit distance Din, and the upper limit distance Dout, as shown in FIG.

[0077] Furthermore, when consecutive targets are determined to be consecutive obstacles outside the travel lane, the upper limit thresholds (upper limit angle θout, upper limit distance Dout) and lower limit thresholds (lower limit angle θin, lower limit distance Din) of the hysteresis determination from the next time onwards may be increased respectively to set the upper limit angle θout', upper limit distance Dout', lower limit angle θin', and lower limit distance Din' to be less strict in determining consecutive obstacles outside the travel lane. This makes it easier to determine consecutive obstacles from the next time onwards and makes it harder to cancel the determination, resulting in stable determination.

[0078] It should be noted that the secondary determination process may be performed using a single angle threshold θth and distance threshold Dth instead of hysteresis control.

[0079] It is also possible to assume that there is another roadside object beyond the arc of the continuous roadside object. For this reason, in areas where it is assumed that a roadside object exists, the threshold value for the distance D may be increased to stably determine the roadside object (obstacle).

[0080] <Modification> In this modification, the radius R formed by successive targets and the vehicle speed V of the vehicle are used as index values, and the operation determination unit 105 performs a secondary determination that the successive targets are successive obstacles outside the travel path when the radius R is less than a predetermined radius threshold Rth and the vehicle speed V is less than a predetermined vehicle speed threshold Vth. The predetermined radius threshold Rth and the predetermined vehicle speed threshold Vth correspond to the angle threshold θth and the distance threshold Dth, respectively, and can be performed by substituting them into the processing procedure shown in Fig. 9. Note that hysteresis control and the like can also be applied to this modification.

[0081] 11 is an explanatory diagram for explaining the calculation of the radius R, which is an index value used in the secondary determination process by the operation determination unit 105. The operation determination unit 10 first selects three obstacles ni, nj, and nk. These three obstacles are selected so that the adjacent distance D is smaller than the distance threshold Dth. For example, the distance dij between the obstacles ni and nj and the distance djk between the obstacles nj and nk can be calculated using the following equations (6) and (7), respectively. dij=√((x i -x j ) 2 +(y i -y j ) 2 ) ···(6) djk=√((x j -x k ) 2 +(y j -y k ) 2 ) ···(7)

[0082] The perpendicular bisector of the line connecting the obstacles ni and nj can be expressed by the following equation (8). (y-(y i +y j ) / 2) =-(x i -x j ) / (y i -y j )*(x-(x i +x j )) / 2 ···(8) Similarly, the perpendicular bisector of the line connecting obstacles nj and nk can be drawn. Then, the position of the intersection N of these two perpendicular bisectors is found. The distance between this intersection N and obstacles ni, nj, and nk is the radius R. Arc CA in Figure 11 is an arc with radius R centered at intersection N.

[0083] In this modification, if the radius R of the arc is too small for the vehicle speed V, it is determined that there is a possibility of a collision, and an alarm is output at the first determination alarm timing so as not to delay the alarm timing.

[0084] It is also possible to add a determination based on the radius R and the vehicle speed V to the determination based on the index values ​​of the angle θ and the distance D. In this case, the determination may be an AND condition or an OR condition of each determination. Also, in this modification, hysteresis control may be performed.

[0085] Furthermore, the configurations illustrated in the above-described embodiments and modifications are merely functional schematics and are not necessarily physically configured as shown. In other words, the distribution and integration of each device and component is not limited to that illustrated, and all or part of them can be functionally or physically distributed and integrated in any unit depending on various usage situations, etc. [Explanation of symbols]

[0086] 1 Vehicle control device 11 ECU 12 Microcomputer 13 CPU 14 Memory 21 Camera 22 Vehicle speed sensor 23 Steering angle sensor 24 Yaw rate sensor 25 Brake Actuator 26 Alarm 101 Vehicle position prediction unit 102 Target position prediction unit 103 Collision determination unit 104 Collision Pattern Prediction Unit 105 Operation determination unit 106 Executive Department D distance R radius T target V Vehicle speed X,Y vehicle θ angle

Claims

1. A vehicle control device, a vehicle position prediction unit that predicts a future vehicle position indicating a position of a vehicle equipped with the vehicle control device after a predetermined time; a target position prediction unit that predicts a future target position indicating a position of the target after the predetermined time; a collision determination unit that determines whether or not there is a possibility of a collision between the vehicle and the target based on the vehicle future position and the target future position; a collision type prediction unit that predicts a collision type between the vehicle and the target based on a relationship between a traveling direction of the vehicle and a traveling direction of the target when it is determined that there is a possibility of a collision between the vehicle and the target; an operation determination unit that performs a primary determination of the timing of issuing an alarm and activating an automatic brake to avoid a collision with the target object according to the collision type predicted by the collision type prediction unit, and further performs a secondary determination of whether or not the target object is a continuous obstacle outside a continuous arc-shaped roadway based on the result of the primary determination and on index values ​​obtained from multiple end point positions of geometric information related to the target object; an execution unit that delays the activation timing of the alarm that was primarily determined by the activation determination unit and executes the alarm at a time when a collision between the vehicle and the target is predicted, when the activation determination unit makes a secondary determination that the target is a continuous obstacle outside the traveling path; A vehicle control device comprising:

2. the index values ​​are the distance between successive targets and the angle between the successive targets, 2. The vehicle control device according to claim 1, wherein the operation determination unit performs a secondary determination that the successive targets are successive obstacles outside a travel path when the distance is less than a predetermined distance threshold and the angle is less than a predetermined angle.

3. the index value is a radius formed by successive targets and a vehicle speed of the vehicle; 2. The vehicle control device according to claim 1, wherein the operation determination unit performs a secondary determination that the successive targets are successive obstacles outside the travel path when the radius is less than a predetermined radius threshold and the vehicle speed is less than a predetermined vehicle speed threshold.

4. The vehicle control device according to any one of claims 1 to 3, wherein the operation determination unit performs a secondary determination of whether or not the consecutive objects are consecutive obstacles outside the travel path by a hysteresis determination using the index value, and secondary determines that the consecutive objects are consecutive obstacles outside the travel path on the condition that they are consecutive obstacles outside the travel path for a predetermined period of time, and secondary determines that the consecutive objects are not consecutive obstacles outside the travel path on the condition that they are not consecutive obstacles outside the travel path for the predetermined period of time.

5. 5. The vehicle control device according to claim 4, wherein, when the successive targets are determined to be successive obstacles outside the travel path, the operation determination unit increases the upper and lower thresholds of the hysteresis determination for the next successive targets and thereafter, thereby making the determination of successive obstacles outside the travel path more lenient.

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