VEHICLE COLLISION DETERMINATION DEVICE

Abstract

Vehicle collision determination device for determining the risk of a collision between a vehicle and a moving object as an obstacle during a curve of the vehicle, comprising: - a position calculation unit (42) configured to calculate a target trajectory (L2), which is a trajectory (L2) of the moving object as the target, to calculate a vehicle entrainment trajectory (L1), which is a trajectory of the vehicle during cornering, and to calculate a collision position, where a collision between the vehicle and the target is likely, based on the target trajectory and the vehicle entrainment trajectory; - a time calculation unit (44) configured to calculate a time to collision (TTC), which is the time the target needs to reach the collision position, based on the target's velocity of movement; and - a risk determination unit (45) configured to determine, in response to the time to collision being equal to or less than a predefined determination threshold, that there is a risk of collision between the vehicle and the target, wherein - the position calculation unit is configured to calculate a first point (PA) and a second point (PB) from the vehicle's entrainment trajectory and the target's trajectory, and to calculate a nearest collision point, which is an intersection where a line segment (La), representing a relationship between the target's arrival distance and arrival time for each of the first and second points, and a line segment (Lb), representing a relationship between the vehicle's arrival distance and arrival time for each of the first and second points, intersect as the collision position, where the target's arrival distance for each of the first and second points is a distance traveled by the target to each of the first and second points, and the target's arrival time for each of the first and second points is a time the target takes to reach each of the first and second points.to reach each of the first point and the second point, calculated from a moving speed of the target, the arrival distance of the vehicle for each of the first point and the second point is a distance traveled by the vehicle to each of the first point and the second point, and the arrival time of the vehicle for each of the first point and the second point is a time the vehicle needs to reach each of the first point and the second point, calculated from a driving speed of the vehicle, , - the time calculation unit is configured to calculate the time both the target and the vehicle need to reach the nearest collision point, rather than the time until the collision, and - the position calculation unit is configured to respond to the fact that there are two intersection points (X1, X2) where the target's trajectory intersects an outer curve trajectory of the vehicle belonging to the vehicle's sweep trajectory, to place the first point either on the nearest point (A1) to a center of rotation of the vehicle along a line segment connecting the two intersection points, or on the intersection point (X2) that is farther from the target's current position among the two intersection points, whichever is closer to the target's current position, and to place the second point on the intersection point (X1) that is closer to the target's current position among the two intersection points.

Description

[Technical field]

[0001] The present disclosure relates to a vehicle collision determination device for determining the probability of a collision between a vehicle and a moving object that constitutes an obstacle to the vehicle. [State of the art]

[0002] For example, JP 2019-012 345 A discloses a conventional device for reducing collision damage when turning right or left, which determines whether a vehicle is likely to collide with an obstacle. This device determines the probability of a collision between the vehicle and the obstacle based on a relationship between the vehicle's turning trajectory when turning right or left and the position of the obstacle, in order to prevent the collision when the vehicle turns right or left.Specifically, the device considers the vehicle's footprint to be rectangular, estimates the trajectory of each vertex, determines the intersection of a line segment connecting the obstacle's coordinate position and the vehicle's center of rotation with the vehicle's trajectory, and calculates the distance traveled from the vehicle's current position to the intersection. The device then sets thresholds for the offset distance from the obstacle's coordinate position to the intersection, for the distance traveled, and for a grace period until each vertex of the vehicle reaches the intersection. Based on whether all conditions are met, the device determines the collision risk between the vehicle and the obstacle.

[0003] The device disclosed in JP 2019-012 345 A cannot accurately determine the collision risk because it does not adequately consider the speed of the obstacle and assumes that the obstacle is moving towards the vehicle's center of rotation. For example, since only the trajectory of the vehicle's front in the direction of travel is taken into account, the device described in JP 2019-012 345 A may fail to determine that a collision risk exists in a situation where the vehicle collides with an obstacle due to being swerved while cornering. Consequently, there is a risk that the device will not properly warn the driver of the danger of a collision or that the vehicle will not be steered in such a direction.

[0004] From JP 2008-213 535 A, a collision prediction device is also known, comprising: a trajectory prediction device for predicting the trajectory of a self-propelled vehicle, a position relationship detection device for detecting a relative position relationship between a collision target moving body and the self-propelled vehicle, a collision position calculation device for calculating a collision position with the collision target moving body in the self-propelled vehicle based on the predicted trajectory and the relative position relationship, and a collision direction prediction device for predicting a collision direction of the collision target moving body with respect to the self-propelled vehicle.and a collision surface selection device for selecting a collision surface with the collision target moving body in the own vehicle based on the predicted collision direction of the collision target moving body with respect to the own vehicle, wherein the collision position calculation device calculates a collision position with the collision target moving body based on the selected collision surface. [Summary of the invention]

[0005] The purpose of the present disclosure is to provide a vehicle collision detection device that is capable of more accurately determining the risk of a collision with a moving object as an obstacle.

[0006] The problem is solved by the subject matter of the independent claims. Advantageous further developments are specified in the dependent claims.

[0007] According to the invention, the time until the collision is calculated taking into account the trajectory and speed of the moving object, in addition to the vehicle's trajectory. In this way, the time until the collision can be precisely determined, and the risk of a collision between the vehicle and the moving object can be assessed more accurately.

[0008] The reference numerals in parentheses appended to the components or the like merely show examples of the correspondence between the components or the like and the specific components described in relation to the embodiments described below. [Brief description of the drawings] Fig. Figure 1 shows a block diagram of a vehicle collision detection system according to a first embodiment of the present disclosure; Fig. Figure 2 shows a flowchart of a vehicle collision avoidance process executed by a control ECU; Fig. Figure 3 shows a case in which there are two points of intersection between the trajectory of a self-propelled vehicle and the trajectory of a target; Fig. Figure 4 illustrates how to calculate the time until the collision; Fig. Figure 5 shows a case in which there is only one point of intersection between the trajectory of the own vehicle and the trajectory of a target, and the trajectory of the target intersects one side of the own vehicle; and Fig. Figure 6 shows a case in which there is only one intersection between the trajectory of the own vehicle and the trajectory of a target, and the target moves from inside to outside an area of ​​the trajectory of the own vehicle. [Description of the embodiments]

[0009] Embodiments of the present disclosure are described below with reference to the accompanying drawings. In the following embodiments, as in the drawings, identical or equivalent parts are designated with the same reference numerals, and the same description is assumed for parts with the same reference numerals. (First embodiment)

[0010] A vehicle collision detection device of this embodiment is described below. In the present embodiment, the vehicle collision detection device is applied to a vehicle motion control system, wherein the vehicle collision detection device determines a collision risk between the vehicle and a moving object that is an obstacle, and the motion control of the vehicle is based on the result of the determination performed by the vehicle collision detection device.

[0011] First, the configuration of the vehicle motion control system is to be determined with reference to Fig. 1 described.

[0012] As in Fig. As shown in Figure 1, the vehicle motion control system includes an environmental monitoring camera 10, an electronic detection control unit (ECU) 20, sensors 30, a control ECU 40, a brake ECU 50 and the like.

[0013] The perimeter monitoring camera 10 captures images of the vehicle's surroundings and outputs image data as detection information to the detection ECU 20. The perimeter monitoring camera 10 corresponds to a perimeter monitoring device. Since obstacles are monitored by capturing image data of the vehicle's surroundings, the perimeter monitoring camera 10 is used here as an example. However, since it is sufficient to monitor obstacles in the vehicle's surroundings, other types of obstacle monitoring devices, such as millimeter-wave radar, can also be used. Although only one perimeter monitoring camera 10 is shown here, it is advantageous to provide multiple perimeter monitoring cameras 10, such as a front camera, a rear camera, and side cameras, so that obstacles can be monitored in each direction of travel of the vehicle, e.g., forward or reverse.

[0014] The detection ECU 20 contains a microcomputer consisting of a central processing unit (CPU), read-only memory (ROM), read / write memory (RAM), an input / output interface (I / O), and other components. The detection ECU 20 receives data from the environmental monitoring camera 10, detects moving objects under obstacles, and calculates the speed and direction of movement of each moving object. Specifically, the detection ECU 20 includes an input signal processing unit 21 and an image processing unit 22.

[0015] The input signal processing unit 21 captures the image data from the environmental monitoring camera 10 as an input signal, processes the image data by signal processing as required and forwards the image data or its processed data to the image processing unit 22.

[0016] Based on the image data, the image processing unit 22 extracts various elements of information about moving objects in the vicinity of the vehicle. The image processing unit 22 is configured to include a motion object detection unit 23 and an information acquisition unit 24.

[0017] The motion object detection unit 23 uses image data to detect moving objects emerging from or beneath obstacles in the vicinity of the vehicle. Since the image data contains pictures of various obstacles in the vehicle's environment, moving objects are detected from these images. For example, if the image data includes a picture of a person or a small car, the motion object detection unit 23 will recognize these as moving objects. Because the image data from the environmental monitoring camera 10 is acquired in each predefined image recognition cycle, moving obstacles can be extracted from the image data and recognized as moving objects at different times.

[0018] Although the image data may contain moving objects that are far from the vehicle, the distances to these moving objects can be estimated using image recognition technology or similar methods. Therefore, the motion object detection unit 23 can only detect moving objects that are within a predefined distance of the vehicle. This predefined distance for detecting moving objects can be set as a fixed distance or as a variable value depending on the vehicle's speed, so that the higher the vehicle speed, the greater the predefined distance.

[0019] The information acquisition unit 24 captures various pieces of information about each moving object detected by the motion object detection unit 23. Specifically, the information acquisition unit 24 captures information about the speed and direction of movement of the moving object. For example, using the image data output by the environmental monitoring camera 10 in each predefined image recognition cycle, the magnitude and direction of the moving object's movement at different times can be calculated from the image data, and the speed of movement can be calculated from the time interval of the image data and the magnitude of the moving object's movement.

[0020] In this way, when a moving object is detected and various elements of information about the moving object are detected, the motion object detection unit 23 outputs the data as recognition information to an in-vehicle LAN (local network within the vehicle) 60, such as a Controller Area Network (CAN).

[0021] The sensors 30 acquire vehicle information, including various elements of information about the driving of the vehicle. These sensors include a vehicle speed sensor 31, a steering angle sensor 32, and the like.

[0022] The vehicle speed sensor 31, which corresponds to a vehicle speed sensing unit, is configured to output a sensing signal corresponding to the vehicle's own speed as vehicle speed information to the in-vehicle LAN 60. The vehicle speed sensor 31 is used here as an example of the speed sensing unit. However, since the brake ECU 50 (described below) also handles or processes vehicle speed information, the brake ECU 50 can be used as the vehicle speed sensing unit. For example, since the brake ECU 50 calculates an estimated vehicle speed from the sensing signal of a wheel speed sensor for brake control, the brake ECU 50 can be configured to output the estimated vehicle speed as vehicle speed information to the LAN 60.

[0023] The steering angle sensor 32 outputs detection signals corresponding to the steering angles of the vehicle based on steering operations or the like as steering information to the in-vehicle LAN 60.

[0024] The control ECU 40 is configured as a microcomputer with a central processing unit (CPU), read-only memory (ROM), read / write memory (RAM), an input / output interface (I / O), and other components. It serves as a control unit that executes various processes based on programs stored in the ROM or similar memory. The control ECU 40 corresponds to the vehicle collision detection device. In the present embodiment, the control ECU 40 receives detection information from the detection ECU 20 and vehicle information from the sensors 30 via the in-vehicle LAN 60, determines the risk of a collision with a moving object, and submits a request for vehicle motion control based on the determination result.In particular, the control ECU 40 contains an input processing unit 41, a position calculation unit 42, a specification storage unit 43, a time calculation unit 44, a control query unit 45 and an output processing unit 46.

[0025] The input processing unit 41 is configured to receive the detection information output by the ECU 20 via the in-vehicle LAN 60 and to receive vehicle speed information from the vehicle speed sensor 31 and steering angle information from the steering angle sensor 32 as the vehicle information. After receiving the detection information, the input processing unit 41 forwards it to the position calculation unit 42.

[0026] The position calculation unit 42 calculates a vehicle trajectory, which is the expected trajectory of the vehicle, and a target trajectory, which is also the expected trajectory of the target, as well as intersection points between the vehicle trajectory and the target trajectory, considering the moving object as a target with a collision risk with the vehicle, and calculates the number of intersection points. The vehicle trajectory is calculated based on the shape and dimensions of the vehicle and the steering angle information stored in the specification memory unit 43, as described below. The target trajectory is calculated based on the direction of movement of the moving object, which is the target specified by the detection information.For example, the points of intersection between the vehicle's trajectory and the target's trajectory are calculated by formulating the vehicle's trajectory and the target's trajectory using mathematical expressions with an arbitrary position of the vehicle as the origin (0, 0) and then finding the points of intersection of the mathematical expressions.

[0027] The specification storage unit 43, in which vehicle specifications of the self-propelled vehicle are pre-stored, contains at least various specifications, such as a vehicle shape and turning radii corresponding to steering angles, which are stored to determine a collision risk of the self-propelled vehicle with a target. Based on the specifications of the self-propelled vehicle stored in the specification storage unit 43, the position calculation unit 42 calculates the positions of parts of the self-propelled vehicle, such as the positions of its four corners and sides, and calculates a turning radius and a trajectory of the self-propelled vehicle.

[0028] The time calculation unit 44 calculates the time until collision (TTC) at the nearest collision point between the vehicle and a target. The time until collision (TTC) is calculated based on the number of intersection points calculated by the position calculation unit 42. The calculation method is described in more detail below.

[0029] The control query unit 45 determines whether there is a risk of collision between the vehicle and a target. If a risk of collision is determined, the control query unit 45 requests a vehicle motion controller to avoid the collision. The control query unit 45 corresponds to a risk determination unit. In the present embodiment, the control query unit 45 requests the vehicle motion controller to avoid the collision between the vehicle and the target when the time to collision (TTC) calculated by the time calculation unit 44 is equal to or less than a predefined time corresponding to a determination threshold.For example, the predefined time, which serves as the threshold for comparison with the time to collision (TTC), is set to 0.5 s or 1 s (second), so that vehicle motion control is performed in situations where the vehicle is likely to collide with a target immediately. The control request unit 45 then calculates a control request value required to avoid the collision between the vehicle and the target, in this case, a braking request value required to stop the vehicle.

[0030] The output processing unit 46 outputs the control request value calculated by the control request unit 45, in this case the brake request value, to the in-vehicle LAN 60. Thus, each component of the control ECU 40 is configured as described above.

[0031] The Brake ECU 50 is configured as a microcomputer, with a central processing unit (CPU), read-only memory (ROM), read / write memory (RAM), an input / output (I / O) interface, and other components. The Brake ECU 50 controls the vehicle's braking force by controlling an actuator to regulate brake fluid pressure (not shown). For example, by controlling a pump drive motor and various control valves contained within a brake control actuator, the wheel cylinder pressure is automatically generated to produce the desired braking force. This allows the vehicle to be stopped before it collides with a target.

[0032] The vehicle motion control system of the present embodiment is configured as described above. The vehicle collision detection performed by the vehicle motion control system and the vehicle motion control based thereon are described below with reference to the [reference to be added]. Fig. Figure 2 describes the vehicle collision avoidance process performed by the control ECU 40. This process occurs in each predefined control cycle. In cases where it is desired to perform a vehicle collision detection only when the vehicle speed is lower than the predefined speed, such as 10 km / h or less, the vehicle collision detection can be performed, provided that the vehicle speed is lower than the predefined speed as a trigger condition. Furthermore, this process can be performed for both the forward and reverse directions of travel of the vehicle. However, it can only be performed for one of them.

[0033] First, in step S100, the control ECU 40 calculates a ripple trajectory of the own vehicle. The ripple trajectory refers to an area bounded by an outer and an inner curve trajectory of the own vehicle, i.e., a trajectory of the own vehicle taking into account the shape of the own vehicle. In particular, the control ECU 40 receives steering angle information via the in-vehicle LAN 60 and calculates the own vehicle trajectory based on the shape and dimensions of the own vehicle, which are stored in the specification memory unit 43, and the steering angle information. Although in the present embodiment the trajectories of all parts of the own vehicle, including the outer and inner curve trajectories, are calculated, a collision with a target on the outside of the curve, or during cornering by the own vehicle, should be taken into account.Therefore, of the possible motion paths, only the outer curve motion path can be calculated as the vehicle's own motion path.

[0034] The control ECU 40 then calculates a trajectory for the target in step S105 and determines whether this trajectory intersects with the entrainment trajectory of the own vehicle calculated in step S100. An intersection of the target and entrainment trajectories typically occurs when they meet on the outside of the turn. Therefore, this step determines whether the target and the outside turn trajectory of the own vehicle overlap. If the answer is yes, the control ECU 40 proceeds to step S110, as there is a risk of collision between the own vehicle and the target. If the answer is no, the control ECU 40 terminates the process, as there is no risk of collision between the own vehicle and the target.

[0035] In step S110, the control ECU 40 determines whether there are two intersection points between the entrainment trajectory of the own vehicle calculated in steps S100 and S105 (in this case, the trajectory on the outside of the own vehicle's turn) and the trajectory of the target. If the answer is yes, the control ECU 40 proceeds to step S115. Otherwise, the control ECU 40 proceeds to step S165.

[0036] In step S115 and subsequent steps, the control ECU performs 40 different process steps to calculate the nearest collision point between the vehicle and the target when the number of intersection points is two. These process steps are described with reference to Fig. 3 described.

[0037] In step S115, the control ECU 40 calculates the nearest point A1 to the center of rotation of the self-propelled vehicle V, along the line segment connecting the two intersection points. In step S120, the control ECU 40 calculates the intersection point A2 on the side facing away from the target Tg. Regarding the trajectory of the self-propelled vehicle, for example, as in Fig. Figure 3 shows that the direction of travel of the vehicle V is reverse and the target Tg is moving in one direction along the side of the vehicle V. In such a case, there are two points of intersection of the entrainment path L1 and the path of the target L2, X1 and X2. In the example of Fig. 3. The perpendicular to the line segment connecting the two intersection points X1 and X2 passes through the center of rotation O. Therefore, the intersection of this perpendicular with the line segment connecting the intersection points X1 and X2 is the nearest point A1. The intersection point X2 that is furthest from the target Tg of the intersection points X1 and X2 is intersection point A2.

[0038] The control ECU 40 then determines in step S125 whether the nearest point A1 is closer to the vehicle than the intersection point A2. In this process step, it is determined whether the nearest point A1 or the intersection point A2 is closer to the vehicle V. If the answer is YES, the control ECU 40 proceeds to step S130 and selects the nearest point A1 as a point PA, corresponding to the first point. If the answer is NO, the control ECU 40 proceeds to step S135 and then selects the intersection point A2 as the point PA, corresponding to the first point. That is, the control ECU 40 designates the point PA that is closer to the vehicle from the nearest point A1 and the intersection point A2.

[0039] The control ECU 40 then proceeds to step S140 and calculates which of the two intersection points X1 and X2 is closer to the target, setting it as point PB, which corresponds to a second point. In the example of Fig. 3 is the intersection point X1, point PB. Subsequently, the control ECU 40 proceeds to step S145 and calculates an arrival distance and arrival time for the destination Tg and the own vehicle V for each of the points PA and PB. The arrival distance and arrival time of the destination Tg for each of the points PA and PB are calculated based on the recognition information provided by the ECU 20.

[0040] For example, the control ECU 40 calculates the coordinates of points PA and PB, as well as the coordinates of the target Tg, relative to any position of the vehicle V as the origin (0, 0). From the coordinates of points PA and PB and the coordinates of the target Tg, the control ECU 40 can calculate the distance of the target Tg to each of points PA and PB (hereinafter referred to as the target's arrival distance). From the target Tg's arrival distance to each of points PA and PB and the target Tg's speed, the control ECU 40 can further calculate the time required for the target Tg to reach each of points PA and PB (hereinafter referred to as the target's arrival time).

[0041] As in Fig. As shown in Figure 3, the distance from the vehicle V to each of points PA and PB (hereinafter referred to as the vehicle arrival distance) is calculated by drawing an arc C passing through each of points PA and PB, with the vehicle V's center of rotation as the circle's center point, and then calculating the minimum distance from each of points PA and PB to the intersection Z of arc C and the vehicle V. From the vehicle arrival distance to each of points PA and PB and the vehicle's speed, the control ECU 40 can further calculate the time required for the vehicle V to reach each of points PA and PB (hereinafter referred to as the vehicle arrival time).

[0042] The control ECU 40 then proceeds to step S150 and, based on the result of the calculation in step S145, calculates the nearest collision point where the own vehicle V and the target Tg will collide earliest, by linear approximation, and calculates a time to collision TTC, which is the minimum time to collision that both the own vehicle V and the target Tg need to reach the nearest collision point and collide with each other.

[0043] As in Fig. As shown in Figure 4, the horizontal axis represents the distance from the vehicle V, and the vertical axis represents the arrival time of the vehicle and the arrival time of the destination. The arrival time of the vehicle and the arrival time of the destination are plotted against each of the points PA and PB. Then, the line segment La, connecting the arrival times of the destination plotted against points PA and PB, and the line segment Lb, connecting the arrival times of the vehicle plotted against points PA and PB, are recorded. These line segments each represent a line segment that shows the relationship between the arrival distance of the destination and the arrival time of the destination, and a line segment that shows the relationship between the arrival distance of the vehicle and the arrival time of the vehicle. Subsequently, an intersection point of these line segments La and Lb is calculated.The horizontal axis coordinate of this intersection point represents the nearest collision point, and the vertical axis coordinate of this intersection point is the time to collision (TTC). The nearest collision point represents a specific position between points PA and PB on the target's trajectory. The time to collision (TTC) at the intersection of line segment La and line segment Lb represents the time required for both the target Tg and the own vehicle V to reach the nearest collision point.

[0044] In this way, the time until collision TTC, i.e. the minimum time until collision, can be calculated accurately by taking into account not only the speed and trajectory of the own vehicle V, but also the speed and direction of movement of the target Tg.

[0045] The control ECU 40 then proceeds to step S155 and determines whether the time to collision (TTC) is less than a predefined time interval, known as a determination threshold. The determination threshold is a predefined value set taking into account the driver's reaction speed and the time the vehicle needs to avoid a collision, such as 0.5 or 1 second, as described above. If the answer is NO, the control ECU 40 terminates the process. If the answer is YES, the control ECU 40 proceeds to step S160, outputs a control query value, and then terminates the process.Specifically, the control request unit 45 calculates the control request value required to induce the own vehicle to avoid a collision with the target within the predefined time period—in this case, the braking request value required to stop the movement of the own vehicle V—and outputs the braking request value from the output processing unit 46 to the in-vehicle LAN 60. Upon receiving information about this braking request value from the in-vehicle LAN 60, the brake ECU 50 controls the actuator for controlling the brake fluid pressure to generate braking force, thereby bringing the own vehicle to a standstill before a collision with the target Tg. In this way, the collision between the own vehicle V and the target Tg is avoided.

[0046] If the answer in step S110 is NO, the control ECU 40 proceeds to step S165. In step S165 and the following steps, the control ECU 40 performs various process steps to calculate the nearest collision point between the vehicle V and the target Tg, for example, in cases where there is only one intersection point.

[0047] In step S165, the control ECU 40 determines whether the side of the own vehicle V intersects the path of motion of the target. If the answer is YES, the control ECU 40 proceeds to step S170 and subsequent steps to perform various process steps to calculate the nearest collision point between the side of the own vehicle V and the target Tg in a case where the side of the own vehicle V is likely to collide with the target Tg. This process step is described below with reference to Fig. 5 described.

[0048] First, in step S170, the control ECU 40 calculates the intersection point between the side of the own vehicle V and the path of the target and defines it as point PA, which corresponds to the first point. As in Fig. As shown in Figure 5, assuming that the vehicle V is traveling in reverse and the target Tg is in a right-hand reverse direction, and that the target Tg's trajectory is in the direction of the vehicle V, the intersection of the target Tg's trajectory and the right side of the vehicle V is determined to be point PA. This point PA represents the position on the target Tg's trajectory with the shortest distance from the side of the vehicle V to the target Tg. The control ECU 40 then proceeds to step S175 and calculates the intersection between the vehicle's trajectory (in this case, the outer curve trajectory) and the target's trajectory. This intersection is defined as point PB, which corresponds to the second point.

[0049] The control ECU 40 then proceeds to step S180 and calculates the arrival distance and arrival time of the destination Tg and the vehicle V for each of the points PA and PB. The procedure for calculating the arrival distance and arrival time is performed in this case, as in step S145 described above, based on the recognition information provided by the ECU 20. That is, an arc C passing through each of the points PA and PB is drawn with the center of rotation of the vehicle V as the circle's center point, and then the minimum distance to the intersection of the arc and the vehicle V is calculated as the vehicle's arrival distance. Since point PA indicates a point on the side of the vehicle V, the arrival distance can be set to zero.The control ECU 40 calculates, as the arrival time of the vehicle V, the time required for the vehicle V to reach each of the points PA and PB, based on the arrival distance and the vehicle's travel speed. The control ECU 40 then performs the same process steps as in step S150 and the subsequent steps, and terminates the process.

[0050] If the answer in step S165 is NO, the control ECU 40 proceeds to step S185 and the subsequent steps, in which the control ECU 40 performs various process steps to calculate the nearest collision point between the own vehicle V and the target Tg, in a case where the target Tg is within the area of ​​the entrainment trajectory of the own vehicle V. This process step is described below with reference to Fig. 6 described.

[0051] First, in step S185, the control ECU 40 determines whether the target's position lies within the entrainment path of the own vehicle V, i.e., within the area bounded by the outer and inner curve paths of the own vehicle. As in Fig. As shown in Figure 6, the answer in step S185 is YES if we assume that the direction of travel of the own vehicle V is reverse and the target Tg is behind or beside the own vehicle V. If the answer is YES, the control ECU 40 proceeds to step S190 and then calculates the current position of the target Tg and sets it as point PA, which corresponds to the first point. The control ECU 40 then proceeds to step S195 and calculates the intersection point between the ram-like motion of the own vehicle and the motion of the target, and sets this intersection point as point PB, which corresponds to the second point. For example, if, as in Figure 6, the target Tg is located behind or beside the own vehicle V, the control ECU 40 would then proceed to step S195. Fig. Figure 6 shows that if the target position is already within the area of ​​the vehicle's trajectory, and the target Tg moves from within to outside this area, its current position is defined as point PA. The intersection of the target Tg's trajectory and the outer curve trajectory of the vehicle V is defined as point PB.

[0052] The control ECU 40 then proceeds to step S200 and calculates the arrival distance and arrival time of the target Tg and the vehicle V for each of the points PA and PB. The procedure for calculating the arrival distance and arrival time is performed in this case, as in step S145 described above, based on the recognition information provided by ECU 20. That is, an arc C passing through each of the points PA and PB is drawn with the center of rotation of the vehicle V as the circle's center point, and then the minimum distance to the intersection of the arc and the vehicle V is calculated as the vehicle's arrival distance. The current position of the vehicle V can be set to a point on its side, and the arrival distance can be set to zero.The control ECU 40 calculates, as the arrival time of the vehicle V, the time required for the vehicle V to reach each of the points PA and PB, based on the arrival distance and the vehicle speed. The control ECU 40 then performs the same process steps as in step S150 and the subsequent steps, and terminates the process.

[0053] As described above, in the present embodiment the time to collision (TTC), i.e., the minimum time in which a collision can occur, is calculated taking into account the speed and direction of the moving object, which serves as the target (Tg), in addition to the vehicle's speed and trajectory (V). In this way, the time to collision (TTC) can be determined precisely, and thus the risk of a collision between the vehicle (V) and the moving object can be assessed more accurately.

[0054] Therefore, it is possible to implement a process responsive to the risk of a collision, for example, in the present embodiment, to generate a braking force via brake control by the brake ECU 50 and thereby stop the movement of the vehicle V before it collides with the moving object. Furthermore, the use of a warning device that alerts the driver to the danger of a collision allows for accurate notification of the driver regarding the risk of a collision, even though this is not shown.

[0055] Furthermore, it is possible to detect a target Tg with a collision risk in a situation where the vehicle V may be pulled into a curve, and to calculate the time to collision (TTC) between the vehicle V and the target Tg. This enables vehicle motion control to avoid a collision between the vehicle V and a moving object, the target Tg, in a situation where being pulled into a curve is possible.

[0056] In the present embodiment, the direction of travel of the vehicle V is reversed. In an alternative embodiment, the direction of travel of the vehicle V can be forwards. (Other embodiments)

[0057] Although the present disclosure is described above in connection with its embodiments, it is not limited to these embodiments but also encompasses various variants and variations to the same extent. Furthermore, various combinations and forms, as well as other combinations and forms comprising only one element, more than, or less than the one described above, also fall within the scope and concept of the present disclosure.

[0058] That is, the time to collision (TTC), i.e., the time a moving object needs to reach a collision position where it is likely to collide with the vehicle, is calculated by considering at least the position, direction of motion, and speed of the moving object. The collision risk can be determined based on the time to collision (TTC). Specifically, based on the vehicle's trajectory and the position, direction, and speed of the moving object as the target, the collision position where the moving object is likely to collide with the vehicle is calculated, as well as the time to collision (TTC), i.e., the time the moving object needs to reach the collision position where it is likely to collide with the vehicle. If the time to collision (TTC) isIf the time required for the moving object to reach the collision position where it is likely to collide with the vehicle lies within a predefined time period, it can be determined that a collision risk exists.

[0059] The collision position at which the moving object is likely to collide with the vehicle does not necessarily correspond to the nearest collision point described in the first embodiment, since the vehicle's speed is not taken into account. However, since at least the position, direction of movement, and speed of the moving object are considered, it is still a collision position where a collision is likely, even if it is not the nearest collision point. The part that calculates the collision position at which the moving object is likely to collide with the vehicle corresponds to the position calculation unit.Therefore, the position calculation unit 42 of the first embodiment described above primarily calculates the intersection point between the entrainment path of the own vehicle and the path of the moving object as the collision position at which the moving object and the own vehicle are likely to collide, whereby this position may also be a position other than the intersection point. For example, in the first embodiment, a position other than the intersection point, such as the current position of the target, is also listed as an example. That is, various positions on the entrainment path can be a collision position at which the moving object is likely to collide with the own vehicle.

[0060] Preferably, the time required by the vehicle to reach the collision position where it is likely to collide with the moving object is also calculated, and if this time falls within a predefined time period, a collision risk can be determined. While the time to collision (TTC) is not limited to cases where, as in the first embodiment, the TTC is calculated taking into account the vehicle's speed and the position, direction of movement, and speed of the moving object, the time to collision (TTC), i.e., the time required by the vehicle to collide with the moving object at its current position, can also be calculated taking into account the vehicle's speed.For example, if the current position of the moving object is the collision position where the vehicle is likely to collide with it, the time required for the vehicle to reach that position is calculated based on its speed. If this time is shorter than a predefined duration, a collision risk is determined. In this way, the collision risk can be determined by considering the vehicle's speed in addition to the speed and direction of movement of the moving object.

[0061] A calculation, as in the first embodiment, of the time to collision TTC taking into account the speed of the own vehicle and the speed of the target allows for a more accurate calculation of the minimum time required for a collision, leading to a more accurate determination of the collision risk.

[0062] In the first embodiment above, the nearest collision point is a collision position where a collision is likely, calculated taking into account the speed and trajectory of the own vehicle and the speed and direction of the moving object, and the time to collision (TTC) is the time required for both the own vehicle and the moving object to reach the nearest collision point.In cases where the collision position, calculated taking into account the speed and direction of motion of the moving object but not the speed of the vehicle, can be a position different from the nearest collision point, any position within an overlap area of ​​the entrainment trajectory L1 and the trajectory L2 of the target can be the collision position where a collision is likely. This includes, for example, an intersection between the outer curve of the entrainment trajectory L1 and the trajectory L2 of the target, or an intersection between the vehicle and the trajectory L2 of the target. In such a case, the time to collision (TTC) can be the time required by either the vehicle or the target alone to reach the collision position where a collision is likely.

[0063] In the embodiments and modifications described above, the control unit and the corresponding method described in the present disclosure can be implemented by a special computer with a processor and a memory, programmed to perform one or more functions embodied by computer programs. Alternatively, the control unit and the corresponding method described in the present disclosure can be implemented by a special computer with a processor formed from one or more special hardware logic circuits, or they can be implemented by one or more special computers with a combination of a processor and a memory, programmed to perform one or more functions, and a processor formed from one or more special hardware logic circuits.Computer programs can be stored as instructions to be executed by a computer on a non-volatile, physical, computer-readable storage medium.

Claims

[1] Vehicle collision determination device for determining the risk of a collision between a vehicle and a moving object as an obstacle during a curve of the vehicle, comprising: - a position calculation unit (42) configured to calculate a target trajectory (L2), which is a trajectory (L2) of the moving object as the target, to calculate a vehicle entrainment trajectory (L1), which is a trajectory of the vehicle during cornering, and to calculate a collision position, where a collision between the vehicle and the target is likely, based on the target trajectory and the vehicle entrainment trajectory; - a time calculation unit (44) configured to calculate a time to collision (TTC), which is the time the target needs to reach the collision position, based on the target's velocity of movement; and - a risk determination unit (45) configured to determine, in response to the time to collision being equal to or less than a predefined determination threshold, that there is a risk of collision between the vehicle and the target, wherein - the position calculation unit is configured to calculate a first point (PA) and a second point (PB) from the vehicle's entrainment trajectory and the target's trajectory, and to calculate a nearest collision point, which is an intersection where a line segment (La), representing a relationship between the target's arrival distance and arrival time for each of the first and second points, and a line segment (Lb), representing a relationship between the vehicle's arrival distance and arrival time for each of the first and second points, intersect as the collision position, where the target's arrival distance for each of the first and second points is a distance traveled by the target to each of the first and second points, and the target's arrival time for each of the first and second points is a time the target takes to reach each of the first and second points.to reach each of the first point and the second point, calculated from a moving speed of the target, the arrival distance of the vehicle for each of the first point and the second point is a distance traveled by the vehicle to each of the first point and the second point, and the arrival time of the vehicle for each of the first point and the second point is a time that the vehicle needs to reach each of the first point and the second point, calculated from a driving speed of the vehicle, - the time calculation unit is configured to calculate the time both the target and the vehicle need to reach the nearest collision point, rather than the time until the collision, and - the position calculation unit is configured to respond to the fact that there are two intersection points (X1, X2) where the target's trajectory intersects an outer curve trajectory of the vehicle belonging to the vehicle's sweep trajectory, to place the first point either on the nearest point (A1) to a center of rotation of the vehicle along a line segment connecting the two intersection points, or on the intersection point (X2) that is farther from the target's current position among the two intersection points, whichever is closer to the target's current position, and to place the second point on the intersection point (X1) that is closer to the target's current position among the two intersection points. [2] Vehicle collision determination device for determining the risk of a collision between a vehicle and a moving object as an obstacle during a curve of the vehicle, comprising: - a position calculation unit (42) configured to calculate a target trajectory (L2), which is a trajectory (L2) of the moving object as the target, to calculate a vehicle entrainment trajectory (L1), which is a trajectory of the vehicle during cornering, and to calculate a collision position, where a collision between the vehicle and the target is likely, based on the target trajectory and the vehicle entrainment trajectory; - a time calculation unit (44) configured to calculate a time to collision (TTC), which is the time the target needs to reach the collision position, based on the target's velocity of movement; and - a risk determination unit (45) configured to determine, in response to the time to collision being equal to or less than a predefined determination threshold, that there is a risk of collision between the vehicle and the target, wherein - the position calculation unit is configured to calculate a first point (PA) and a second point (PB) from the vehicle's entrainment trajectory and the target's trajectory, and to calculate a nearest collision point, which is an intersection where a line segment (La), representing a relationship between the target's arrival distance and arrival time for each of the first and second points, and a line segment (Lb), representing a relationship between the vehicle's arrival distance and arrival time for each of the first and second points, intersect as the collision position, where the target's arrival distance for each of the first and second points is a distance traveled by the target to each of the first and second points, and the target's arrival time for each of the first and second points is a time the target takes to reach each of the first and second points.to reach each of the first point and the second point, calculated from a moving speed of the target, the arrival distance of the vehicle for each of the first point and the second point is a distance traveled by the vehicle to each of the first point and the second point, and the arrival time of the vehicle for each of the first point and the second point is a time that the vehicle needs to reach each of the first point and the second point, calculated from a driving speed of the vehicle, - the time calculation unit is configured to calculate the time both the target and the vehicle need to reach the nearest collision point, rather than the time until the collision, and - the position calculation unit is configured to respond to the fact that there is only one intersection between the target's path of motion and an outer curve path of the vehicle that belongs to the vehicle's sweep path, and that there is one intersection between the target's path of motion and a side of the vehicle, to place the first point on the intersection between the target's path of motion and the side of the vehicle, and to place the second point on the intersection between the target's path of motion and the vehicle's outer curve path. [3] Vehicle collision determination device for determining the risk of a collision between a vehicle and a moving object as an obstacle during a curve of the vehicle, comprising: - a position calculation unit (42) configured to calculate a target trajectory (L2), which is a trajectory (L2) of the moving object as the target, to calculate a vehicle entrainment trajectory (L1), which is a trajectory of the vehicle during cornering, and to calculate a collision position, where a collision between the vehicle and the target is likely, based on the target trajectory and the vehicle entrainment trajectory; - a time calculation unit (44) configured to calculate a time to collision (TTC), which is the time the target needs to reach the collision position, based on the target's velocity of movement; and - a risk determination unit (45) configured to determine, in response to the time to collision being equal to or less than a predefined determination threshold, that there is a risk of collision between the vehicle and the target, wherein - the position calculation unit is configured to calculate a first point (PA) and a second point (PB) from the vehicle's entrainment trajectory and the target's trajectory, and to calculate a nearest collision point, which is an intersection where a line segment (La), representing a relationship between the target's arrival distance and arrival time for each of the first and second points, and a line segment (Lb), representing a relationship between the vehicle's arrival distance and arrival time for each of the first and second points, intersect as the collision position, where the target's arrival distance for each of the first and second points is a distance traveled by the target to each of the first and second points, and the target's arrival time for each of the first and second points is a time the target takes to reach each of the first and second points.to reach each of the first point and the second point, calculated from a moving speed of the target, the arrival distance of the vehicle for each of the first point and the second point is a distance traveled by the vehicle to each of the first point and the second point, and the arrival time of the vehicle for each of the first point and the second point is a time that the vehicle needs to reach each of the first point and the second point, calculated from a driving speed of the vehicle, - the time calculation unit is configured to calculate the time both the target and the vehicle need to reach the nearest collision point, rather than the time until the collision, and - the position calculation unit is configured to, in response to the fact that there is only one intersection between the target's path of motion and an outer curve path of the vehicle that belongs to the vehicle's entrainment path, and a current position of the target lies within a range of the vehicle's entrainment path, set the first point to the current position of the target and set the second point to the intersection between the target's path of motion and the vehicle's outer curve path. [4] Vehicle collision detection device according to claim 2 or 3, wherein the position calculation unit is configured to, in response to the existence of two intersection points (X1, X2) where the path of motion of the target intersects with an outer curve path of motion of the vehicle belonging to the vehicle's sweep path, place the first point either on a point (A1) nearest to a center of rotation of the vehicle along a line segment connecting the two intersection points, or on the intersection point (X2) which is farther from the current position of the target among the two intersection points, depending on which is closer to the current position of the target, and place the second point on the intersection point (X1) which is closer to the current position of the target among the two intersection points. [5] Vehicle collision detection device according to claim 1 or 3, wherein the position calculation unit is configured to, in response to the fact that there is only one intersection between the path of motion of the target and an outer curve path of motion of the vehicle belonging to the sweep path of motion of the vehicle, and that there is an intersection between the path of motion of the target and a side of the vehicle, place the first point on the intersection between the path of motion of the target and the side of the vehicle, and place the second point on the intersection between the path of motion of the target and the outer curve path of motion of the vehicle. [6] Vehicle collision detection device according to claim 1 or 2, wherein the position calculation unit is configured to, in response to the fact that there is only one intersection between the path of motion of the target and an outer curve path of motion of the vehicle which belongs to the entrain path of motion of the vehicle, and a current position of the target lies within a region of the entrain path of motion of the vehicle, set the first point to the current position of the target and set the second point to the intersection between the path of motion of the target and the outer curve path of motion of the vehicle. [7] Vehicle collision detection device according to claim 1, wherein - the position calculation unit is configured to, in response to the fact that there is only one intersection between the target's trajectory and an outer curve trajectory of the vehicle belonging to the vehicle's sweep trajectory, and that there is an intersection between the target's trajectory and a side of the vehicle, to place the first point at the intersection between the target's trajectory and the side of the vehicle, and to place the second point at the intersection between the target's trajectory and the vehicle's outer curve trajectory; and - the position calculation unit is configured to, in response to the fact that there is only one intersection between the target's path of motion and an outer curve path of the vehicle that belongs to the vehicle's entrainment path, and a current position of the target lies within a range of the vehicle's entrainment path, set the first point to the current position of the target and set the second point to the intersection between the target's path of motion and the vehicle's outer curve path.

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