System and procedure for avoiding rear-end cross-traffic collisions

Abstract

A system designed to avoid a rear-end cross-traffic collision, wherein the system features: an obstacle detection unit (20) which detects the position of an obstacle (B) by receiving electromagnetic waves reflected from a reflection point of the obstacle (B); a direction estimation unit (30) which estimates the direction of travel of the obstacle (B) based on the position of the obstacle (B) detected by the obstacle detection unit (10); and a collision determination unit (B) which determines the possibility of a collision with the obstacle (B) on the basis of the direction of travel of the obstacle (B) estimated by the direction estimation unit (30), characterized by a reliability evaluation unit (50) which collects the multiple directions of travel of the obstacle (B) estimated by the direction estimation unit (30) and evaluates an estimated reliability degree for the direction of travel of the obstacle (B) by using the number of directions of travel collected and a variance or standard deviation between the directions of travel collected, wherein, if the reliability level estimated by the reliability evaluation unit (50) is equal to or greater than a preset reliability level, the collision determination unit (40) determines the possibility of a collision with the obstacle (B) on the basis of the direction of travel of the obstacle (B).

Description

Background of the invention: Area

[0001] The invention relates to a system and a method for avoiding a rear-end cross-traffic collision. In particular, the invention relates to a system and a method which, when a vehicle is stopped or reversing, detects an obstacle whose direction of travel intersects the direction of travel of the vehicle and warns the driver of the obstacle. Discussion of the background

[0002] With the development of advanced technologies for autonomous driving, various vehicle safety technologies have also been developed, taking into account driver comfort and safety. These safety technologies have been implemented in actual vehicles.

[0003] In particular, technologies have been developed to determine the possibility of a collision between a specific vehicle and another vehicle or an obstacle, and to warn the driver of that specific vehicle or to steer that specific vehicle. Among these technologies is the Rear Cross Traffic Collision Warning (RCCW) function, which, when a vehicle is stopped or reversing, detects an obstacle approaching from the side and warns the driver.

[0004] The rear cross-traffic alert function uses radar to detect an approaching vehicle. Therefore, a problem arises in that the position of the reflection point on the obstacle detected by the radar varies depending on the distance from the target vehicle.

[0005] Accordingly, since the reflection point on the obstacle, which reflects the reflection back to the radar, is moving, the prior art incorrectly recognizes that the obstacle moving parallel to the specific vehicle will collide with the specific vehicle.

[0006] The foregoing serves only to provide a better understanding of the background of the present disclosure and is not intended to imply that the present disclosure falls within the scope of the prior art already known to those skilled in the art. KR 10 1 843 251 B1 discloses a system for avoiding a rear-end cross-traffic collision with the features of the preamble of claim 1. WO 2018 / 155 439 A1, DE 10 2018 105 014 A1 and DE 10 2017 003 067 A1 disclose further collision prevention systems. overview

[0007] The present disclosure relates to the creation of a system designed to avoid a rear-cross traffic collision in order to solve the problem of erroneously determining that the vehicle is likely to collide with an obstacle traveling parallel to a longitudinal direction of the vehicle.

[0008] Additional features of the invention concepts are detailed in the following description and are partly derived from the description or can be learned through the practical implementation of the invention concepts.

[0009] According to the present disclosure, a system is disclosed which is designed to avoid a rear-cross traffic collision, wherein the system comprises: an obstacle detection unit which detects a position of an obstacle by receiving electromagnetic waves which are reflected from a reflection point of the obstacle; a direction estimation unit which estimates a direction of travel of the obstacle based on the position of the obstacle detected by the obstacle detection unit; and a collision determination unit which determines the possibility of a collision with the obstacle based on the direction of travel of the obstacle estimated by the direction estimation unit.

[0010] The obstacle detection unit can be connected to a radar sensor located at each of the opposite rear ends of a vehicle and can detect the position of the obstacle located behind or beside the vehicle.

[0011] The direction estimation unit can collect the multiple positions of the obstacle detected by the obstacle detection unit and use the multiple collected positions of the obstacle to calculate a ratio between a change in a longitudinal direction position of the obstacle and a change in a lateral direction position of the obstacle, thereby estimating the direction of travel of the obstacle.

[0012] The direction estimation unit can calculate the ratio between the change in longitudinal position and the change in lateral position that occur between a first detected initial position of the obstacle and a current position, thereby determining the direction of travel of the obstacle in real time.

[0013] If the approach angle between the estimated direction of travel of the obstacle and a side axis of a vehicle is within a preset angular range, the collision detection unit determines that there is no possibility of a collision with the obstacle.

[0014] The obstacle detection unit can calculate the lateral distance of the vehicle to the obstacle or the lateral speed of the obstacle by using the detected position of the obstacle, and if the amount of change in the lateral distance to the obstacle or the lateral speed of the obstacle is equal to or less than a preset amount of change, the collision determination unit determines that there is no possibility of a collision with the obstacle.

[0015] According to the invention, the system further comprises a reliability evaluation unit which collects the multiple directions of travel of the obstacle estimated by the direction estimation unit and evaluates an estimated reliability level for the direction of travel of the obstacle by using the number of directions of travel collected and a variance or standard deviation between the directions of travel collected, wherein, if the reliability level estimated by the reliability evaluation unit is equal to or greater than a preset reliability level, the collision determination unit determines the possibility of a collision with the obstacle based on the direction of travel of the obstacle.

[0016] The obstacle detection unit can calculate a vehicle's lateral distance from the obstacle and the obstacle's lateral speed using the detected position of the obstacle, and the collision determination unit can calculate the time until collision based on the calculated lateral distance and lateral speed, and can determine that there is a possibility of collision with the obstacle if the obstacle is within a preset area and the time until collision is equal to or less than a preset time.

[0017] The collision detection unit can adjust the lateral speed of the obstacle using the previously detected lateral speed of the obstacle and the currently detected lateral speed of the obstacle based on the direction of travel of the obstacle.

[0018] The collision detection unit can modify the preset area to exclude a part of an area adjacent to the vehicle from the preset area based on the direction of travel of the obstacle.

[0019] The system may also include a notification display unit that displays a notification to the driver of a vehicle when there is a possibility of a collision with the obstacle as determined by the collision detection unit.

[0020] According to the present disclosure, a method for avoiding a rear-end cross-traffic collision is provided, wherein the method comprises: the reception by a vehicle of electromagnetic waves reflected from a reflection point of an obstacle and the detection of a position of the obstacle; the estimation of a direction of travel of the obstacle based on the detected position of the obstacle;Determining the possibility of a collision with the obstacle based on the detected position of the obstacle or the estimated direction of travel of the obstacle, collecting the estimated multiple directions of travel of the obstacle and evaluating an estimated reliability level for the direction of travel of the obstacle, by using the number of directions of travel collected and a variance or standard deviation between the directions of travel collected, wherein, if the estimated reliability level is equal to or greater than a preset reliability level, the possibility of a collision with the obstacle (B) is determined based on the direction of travel of the obstacle (B).

[0021] According to the present disclosure, the system and method for avoiding rear-cross traffic collisions solve the problem of the erroneous finding that the vehicle is likely to collide with an obstacle moving in a direction parallel to the vehicle.

[0022] It should be noted that both the preceding general description and the following detailed description are exemplary and explanatory and serve to further explain the claimed invention. Brief description of the drawings

[0023] The accompanying drawings, which are included for a further understanding of the invention and are incorporated into and form part of this description, show exemplary embodiments and, together with the description, serve to explain the concepts of the invention. The aforementioned and other problems, features, and other advantages of this disclosure will become clearer in conjunction with the accompanying drawings from the following detailed description, which shows: Fig. 1 a block diagram illustrating a system designed to avoid a rear-cross traffic collision according to an embodiment of the present disclosure. Fig. 2 a flowchart illustrating a method for avoiding a rear-cross traffic collision according to an embodiment of the present disclosure. Fig. 3 A diagram illustrating a reflection point and a principal reflection point of an obstacle located at a great distance and at a short distance from a vehicle when the obstacle and the vehicle are traveling parallel to each other. Fig. 4 a diagram illustrating a preset range according to an embodiment of the present disclosure. Fig. 5 a diagram illustrating a method for determining the direction of travel of an obstacle according to an embodiment of the present disclosure. Fig. 6. A graphic illustrating the direction of travel of an obstacle as a function of the approach angle of the obstacle. Fig. 7 a graphic illustrating a degree of reliability according to an embodiment of the present disclosure. Fig. 8 a diagram illustrating a change in a preset range according to an embodiment of the present disclosure. Detailed description

[0024] Unless otherwise stated, the exemplary embodiments shown are to be understood as indicating exemplary features with varying levels of detail of some ways in which the inventive concepts can be implemented in practice. Therefore, unless otherwise stated, the features, components, modules, layers, films, plates, areas, aspects, etc. (hereinafter referred to individually or collectively as "elements") of the various embodiments can be combined, separated, exchanged, and / or rearranged differently without departing from the inventive concepts.

[0025] The use of cross-hatching and / or shading in the accompanying drawings generally serves to clarify boundaries between adjacent elements. As such, neither the presence nor the absence of cross-hatching or shading conveys or indicates any preference or requirement for specific materials, material properties, dimensions, proportions, commonalities between depicted elements, and / or any other characteristic, attribute, property, etc., of the element, unless otherwise specified. Furthermore, the size and relative dimensions of elements may be exaggerated in the accompanying drawings for clarity and descriptive purposes. If an exemplary embodiment can be implemented differently, a specific process sequence may be performed in a manner other than that described.For example, two processes described sequentially can be carried out essentially simultaneously, or in a reverse order to the one described. Furthermore, identical reference symbols denote identical elements.

[0026] For the purposes of this disclosure, “at least one of X, Y and Z” and “at least one chosen from the group formed by X, Y and Z” may be understood to mean only X, only Y, only Z, or any combination of two or more of X, Y and Z, such as XYZ, XYY, YZ and ZZ. In this case, the expression “and / or” includes any and all combinations of one or more of the aforementioned elements.

[0027] Spatial reference words such as "below," "under," "deeper," "above," "upper," "over," "higher," "lateral" (e.g., as in "side wall") and the like can be used here for descriptive purposes and thus serve to describe the relationship of an element to one or more other elements as depicted in the drawings. In addition to the orientation shown in the drawings, spatial reference words should encompass different orientations of a device in use, operation, and / or manufacture. For example, if a device is inverted in the drawings, elements described as being "below" or "under" other elements or devices would then be arranged "above" the other elements or devices. Thus, the exemplary expression "under" can encompass both an arrangement above and below an element or device.Furthermore, the device may also be oriented differently (for example, rotated by 90 degrees or have a different orientation) and thus the spatial reference descriptors used here must be interpreted accordingly.

[0028] It should also be noted that the terms “essentially” and “approximately” or other similar expressions, when used herein, are used as expressions of approximation and not as expressions of degree, and are employed to take account of inherent variations in measured, calculated and / or provided values ​​which would be recognized by a person of expertise in the field.

[0029] As is common in this field, some embodiments are described and illustrated in the accompanying drawings as functional blocks, units, and / or modules. Those skilled in the art will recognize that these blocks, units, and / or modules are physically implemented by electronic (or optical) circuits, such as logic circuits, discrete components, microprocessors, hard-wired circuits, memory elements, wiring connections, and the like, which may be formed using semiconductor-based fabrication techniques or other manufacturing technologies. When the blocks, units, and / or modules are implemented by microprocessors or similar hardware, they may be programmed and controlled by software (e.g., microcode) to perform various functions discussed herein and may optionally be controlled by firmware and / or software.It is further considered that each block, unit, and / or module may be implemented by dedicated hardware or as a combination of dedicated hardware for performing some functions and a processor (e.g., one or more programmed processors and associated circuitry) for performing other functions. Furthermore, each block, unit, and / or module of some embodiments can be physically separated into two or more interacting and discrete blocks, units, and / or modules without deviating from the scope of the invention. Furthermore, the blocks, units, and / or modules of some embodiments can be physically combined to form more complex blocks, units, and / or modules without deviating from the scope of the invention.

[0030] Specific structural and functional descriptions of embodiments of the invention concepts described in the description or application serve only to illustrate these embodiments. The embodiments of the invention concepts can take numerous different forms, and the embodiments described in this description or application should not be understood as limiting the invention concepts.

[0031] Since the embodiment of the present disclosure can be modified in various ways and can have different forms, certain embodiments are illustrated in the drawings and described in detail in the description or application. The embodiment according to the concept of the invention should not be understood as being limited to a particular disclosure, and it should be noted that all modifications, equivalents, or alternatives that fall within the scope and subject matter of the disclosure are included.

[0032] While the terms "first," "second," etc., used in the description can be employed here to describe different elements, these elements should not be restricted by these terms. These terms serve only to distinguish one element from another. Thus, for example, a first element can be called a second element without departing from the framework of the teaching of the present revelation. Likewise, a second element could also be called a first element.

[0033] It should be noted that when an element is described as "coupled" or "connected" to another element, it may be directly coupled to the other element, or there may be interposed elements between them. Conversely, when an element is described as "directly coupled" or "directly connected" to another element, there are no interposed elements. Other terms used to describe the relationship between elements, such as "between," "immediately between," "adjacent," and "immediately adjacent," should be understood in the same way.

[0034] The terms used in this description serve to describe specific embodiments and are not to be understood as limiting the invention concepts. The singular forms "a" and "the" used here also include the plural forms, unless the context clearly indicates otherwise. It should be noted that terms such as "have" or "comprise" are intended to indicate the presence of features, numbers, steps, actions, elements, parts, or combinations thereof specified in this description, without excluding the possibility of the presence or addition of one or more other features, numbers, steps, actions, elements, and / or combinations thereof.

[0035] Unless otherwise defined, all terms used herein, including technical and scientific terms, have the same meaning as they would be familiar to a person skilled in the art in the field of invention concepts. It should also be noted that the terms used herein are to be interpreted as having a meaning consistent with their meaning in the context of this description and the relevant technical field, and are not to be interpreted in an idealized or overly formal sense, unless expressly defined otherwise herein.

[0036] An exemplary embodiment of the invention concepts is described in detail below with reference to the accompanying drawings. The same reference numerals in all drawings denote identical parts.

[0037] Fig. Figure 1 is a block diagram illustrating a system designed to avoid a rear-cross traffic collision according to an embodiment of the invention concepts. Fig. Figure 2 is a flowchart illustrating a method for avoiding a rear-cross traffic collision according to an embodiment of the invention concepts.

[0038] Referring to the Fig. 1 and Fig. 2 According to an embodiment of the invention, a system is provided which is designed to prevent a rear-end cross-traffic collision, wherein the system comprises: an obstacle detection unit 20 which determines the position of a (in Fig. 3 depicted) obstacle B by receiving electromagnetic waves reflected from a reflection point of the obstacle B; a direction estimation unit 30, which estimates a direction of travel of the obstacle B based on the position of the obstacle B detected by the obstacle detection unit 20; and a collision determination unit 40, which determines the possibility of a collision with the obstacle B based on the position of the obstacle B detected by the obstacle detection unit 20 or the direction of travel of the obstacle B estimated by the direction estimation unit 30.

[0039] The obstacle detection unit 20, the direction estimation unit 30, the collision detection unit 40, a reliability evaluation unit 50, and a notification display unit 60, according to an exemplary embodiment of the invention concepts, can be implemented as a (not shown) non-volatile memory and a (not shown) processor, wherein the non-volatile memory is configured to store data relating to an algorithm configured to control operations of various elements, or to software instructions configured to reproduce the algorithm, and the processor is configured to perform an operation described below by using the data stored in the memory. The memory and the processor can be implemented as separate chips. Alternatively, the memory and the processor can be implemented as a single integrated chip.The processor can be in the form of one or more processors.

[0040] Furthermore, according to an embodiment of the invention, a method for avoiding a rear-cross traffic collision is provided, wherein the method comprises: the reception of electromagnetic waves reflected from a reflection point of the obstacle B by the vehicle A and the detection of a position of the obstacle B in step S100; the estimation of a direction of travel of the obstacle B based on the detected position of the obstacle B in step S200; and the determination of the possibility of a collision with the obstacle B based on the detected position of the obstacle B or the direction of travel of the obstacle B estimated by the direction estimation unit 30 in step S300.

[0041] The obstacle detection unit 20 detects the position of obstacle B. The position of obstacle B can be detected using various sensors, such as a radar sensor 10, an ultrasonic sensor, a lidar sensor, and the like. The obstacle detection unit 20 detects the relative position of obstacle B with respect to vehicle A and calculates the distance of vehicle A from obstacle B.

[0042] The obstacle detection unit 20 detects the position of obstacle B by emitting electromagnetic waves and receiving the electromagnetic waves reflected from a reflection point of obstacle B. In particular, a sensor that emits and receives electromagnetic waves can be provided at the rear end of vehicle A.

[0043] In particular, the obstacle detection unit 20 is connected to the radar sensors 10 provided at each of the opposite rear ends of the vehicle A and detects the position of the obstacle B, which is located behind or beside the vehicle A.

[0044] The radar sensor 10 emits electromagnetic waves, for example microwaves, towards the obstacle 10 and receives the electromagnetic waves reflected by the obstacle B, thereby determining the distance, direction, height, and the like with respect to the obstacle B. The radar sensor 10 is located on opposite sides of the vehicle A and can also be located at the rear of the vehicle A. The detection range of the radar sensor 10 can be an angular area extending from the rear of the vehicle A to opposite sides.

[0045] Furthermore, the obstacle detection unit 20 can detect multiple positions of obstacle B and use a change in the position of the detected obstacle B to calculate the speed of obstacle B. In particular, the obstacle detection unit 20 can separate the distance between vehicle A and obstacle B and the speed of obstacle B into a longitudinal component and a lateral component.

[0046] The collision detection unit 40 can determine the possibility of a collision between vehicle A and obstacle B by using the distance between vehicle A and obstacle B and the speed of obstacle B, each calculated on the basis of the position of obstacle B and another position of obstacle B.

[0047] According to one embodiment of the invention, the collision detection unit 40 can determine the possibility of a collision with obstacle B based on the direction of travel of obstacle B estimated by the direction estimation unit 30. More precisely, the collision detection unit 40 can determine that, considering the direction of travel of obstacle B estimated by the direction estimation unit 30, there is no possibility of a collision between vehicle A and obstacle B, even though a collision was determined to be possible based on the distance between vehicle A and obstacle B and the speed of obstacle B, which were calculated based on one position of obstacle B and another position of obstacle B detected by the obstacle detection unit 20.

[0048] Fig. Figure 3 is a diagram illustrating a reflection point and a principal reflection point of obstacle B, located at a large distance and a small distance from vehicle A, when obstacle B and vehicle A are traveling parallel to each other.

[0049] Referring to Fig. 3. The radar sensor 10, located at the rear of vehicle A, can detect the position of obstacle B behind and beside vehicle A. Reflection points of obstacle B can be located on a front part and a side part close to vehicle A.

[0050] In particular, if the obstacle B is located at a great distance from the rear of vehicle A, a principal reflection point is located on the front part of the obstacle B. If the obstacle B is located at a short distance from vehicle A, a principal reflection point is located on the side of the obstacle B. A great distance can be assumed if the obstacle B is located at least one or more vehicle lengths away from vehicle A, up to the point where the obstacle B overtakes vehicle A. A short distance can be assumed if the obstacle B begins to overtake vehicle A and a portion of the obstacle B is at the same level as vehicle A.

[0051] According to the prior art, the following problem exists: If obstacle B is laterally spaced from vehicle A and travels parallel to the longitudinal direction of vehicle A, there is no possibility of a collision between obstacle B and vehicle A. However, since the main reflection point for vehicle A moves laterally, it is erroneously determined that obstacle B is also moving laterally.

[0052] Here, the longitudinal direction of vehicle A refers to the overall length of vehicle A. The lateral direction of vehicle A refers to the overall width of vehicle A (as in Fig. 4 shown). The main reflection point is the reflection point that is identified as being closest to vehicle A among the reflection points of obstacle B, or it is the reflection point from which the electromagnetic wave with the highest level of a received signal is reflected.

[0053] Therefore, according to one embodiment of the invention, the collision detection unit 40 can determine the possibility of a collision with the obstacle B on the basis of the direction of travel of the obstacle B determined by the direction of travel determination unit 30.

[0054] The obstacle detection unit 20 uses the detected position of obstacle B to calculate the lateral distance of vehicle A from obstacle B and the lateral speed of obstacle B. The obstacle detection unit 40 calculates the time until collision based on the calculated lateral distance and lateral speed. If obstacle B is within a preset area and the time until collision is equal to or less than a preset time, the collision determination unit 40 determines that there is a possibility of a collision with obstacle B.

[0055] More precisely, the obstacle detection unit 20 can calculate the distance of vehicle A from obstacle B and the speed of obstacle B based on the position of obstacle B. Specifically, the obstacle detection unit 20 can separate the distance from obstacle B and the speed of obstacle B into a longitudinal component and a lateral component by using the distance from the detected position of obstacle B and the direction towards it.

[0056] The collision detection unit 40 calculates the time until a collision based on the calculated lateral distance and the calculated lateral speed. If the obstacle B is within the preset area and the time until collision is equal to or less than the preset time, the collision detection unit 40 determines that there is a possibility of a collision with obstacle B.

[0057] Fig. Figure 4 is a diagram illustrating a preset range 400 according to an embodiment of the invention concepts.

[0058] Fig. Figure 4 shows the preset range 400 for obstacle B, which is detected by the radar sensor 10 located at the right rear end of vehicle A. A different preset range for obstacle B detected by the radar sensor 10 located at the left rear end of vehicle A can be preset to be symmetrical to the preset range described above.

[0059] Furthermore, the collision detection unit 40 calculates the time to collision (TTC), and if the calculated time to collision is equal to or less than the preset timez, the collision detection unit 40 determines that there is a possibility of a collision with obstacle B. As an example, the time to collision can be calculated using the following equation: TTCk = Y-axis position, Y-axis velocity = -Yk, Y-velocity where k is the k-th radar frame and TTC means Time to Collision.

[0060] In particular, if the obstacle B is located in the preset area and the time until the collision is equal to or less than the preset time, the collision detection unit 40 determines that there is a possibility of a collision with the obstacle B.

[0061] Fig. Figure 5 is a diagram 500 illustrating a method for estimating the direction of travel of an obstacle B according to an embodiment of the invention concepts. Fig. Figure 6 is a graphic illustrating the direction of travel of an obstacle B according to an approach angle of the obstacle B.

[0062] Referring to the Fig. 5 and Fig. 6 The direction estimation unit 30 collects the multiple positions of the obstacle B which were detected by the obstacle detection unit 20, and uses the collected positions of the obstacle B to calculate a ratio between a change in the longitudinal direction position of the obstacle B and a change in the lateral direction position of the same, thereby estimating the direction of travel of the obstacle B.

[0063] The obstacle detection unit 20 detects the position of obstacle B in real time and thus recognizes multiple positions of obstacle B. The direction estimation unit 30 calculates a change in the position of obstacle B using the multiple positions of obstacle B. As an embodiment, the direction estimation unit 30 can estimate the direction of travel of obstacle B based on a change between the current position of obstacle B and the previously detected position.

[0064] In particular, the direction estimation unit 30 calculates a ratio between a change in the longitudinal direction position and a change in the lateral direction position that occur between the first detected initial position of obstacle B and the current position of obstacle B, thereby estimating the direction of travel of obstacle B in real time.

[0065] More precisely, the approach angle θ kThe distance of obstacle B is estimated as shown in the following equation. Here, the approach angle θ is... k The angle between the lateral axis of vehicle A and the direction of travel of obstacle B is that of obstacle B. θk=tan−1(Xk−XoutputYk−Youtput)

[0066] Since the amount of change from the initial position to the current position of obstacle B is used, the approach angle θ changes. k Not significantly, although the reflection point for the detection of obstacle B varies. Accordingly, the possibility of a collision with obstacle B is not erroneously detected.

[0067] As in Fig. Figure 6 shows that when the approach angle θ k If the approach angle θ is equal to or greater than a first angle, it is determined that the obstacle B is traveling parallel to the vehicle. kIf the second angle is smaller than a certain angle, it is determined that the obstacle B is traveling perpendicular to the vehicle. Furthermore, if the approach angle θ is smaller than a certain angle, it is determined that the obstacle B is traveling perpendicular to the vehicle. k If the angle is smaller than the first angle and equal to or greater than the second angle, it is determined that the obstacle B is traveling diagonally.

[0068] If the approach angle θ k If the angle between the estimated direction of travel of obstacle B and the side axis of vehicle A lies within a preset angular range, the collision detection unit 40 determines that there is no possibility of a collision with vehicle B. The preset angular range can be set to be equal to or greater than the first angle and equal to or less than a right angle (a 90-degree angle).

[0069] The preset angle range can be preset to be greater than the change in the approach angle θ. kis caused by the movement of the main reflection point while obstacle B travels parallel to vehicle A. Furthermore, the preset angle range can be preset to be smaller than the change in the approach angle θ. k In this case, the angle of obstacle B changes near vehicle A, and a collision of obstacle B with vehicle A is actually likely.

[0070] Fig. Figure 7 is a graphic illustrating a degree of reliability according to an embodiment of the invention concepts.

[0071] Referring to the Fig. 7 The system further includes a reliability evaluation unit 50, which collects several directions of travel of the obstacle B estimated by the direction estimation unit 30 and evaluates an estimated reliability level for the direction of travel of the obstacle B by considering the number of directions of travel collected and the variance or standard deviation between the collected approach angles θ k used. Furthermore, if the estimated reliability level evaluated by the reliability evaluation unit 50 is equal to or higher than a preset reliability level, the collision determination unit 40 determines the possibility of a collision with the obstacle B based on the direction of travel of the obstacle B.

[0072] As in Fig. Figure 7 shows the estimated reliability level γ kThe direction of travel of obstacle B can be a function that has as variables the number of collected directions of travel and the variance or standard deviation between the collected directions of travel.

[0073] The estimated reliability for the direction of travel of obstacle B is proportional to the number of collected directions of travel and is inversely proportional to the variance or standard deviation σ. k between the collected directions of travel.

[0074] If the estimated reliability level evaluated by the reliability evaluation unit 50 is equal to or higher than the preset reliability level, the collision determination unit 40 determines the possibility of a collision with the obstacle B based on the direction of travel of the obstacle B.

[0075] More precisely, if the estimated reliability level is equal to or higher than the preset reliability level and the approach angle, according to the direction of travel of obstacle B, is within the preset angle range, it is determined that there is no possibility of a collision with obstacle B.

[0076] If it is determined that the approach angle θ k If the direction of travel of the obstacle B lies within the preset angle range and there is no possibility of a collision with the obstacle B, the collision detection unit 40, according to one embodiment, immediately determines that there is no possibility of a collision.

[0077] According to another embodiment, the collision detection unit 40 can adjust the lateral speed of the obstacle B by using the previously detected lateral speed of the obstacle B and the currently detected lateral speed of the obstacle B based on the direction of travel of the obstacle B.

[0078] More precisely, the collision detection unit 40 determines that there is a possibility of a collision if the time until the collision, calculated using the lateral velocity of obstacle B, is within the preset time.

[0079] Therefore, the collision detection unit 40, when it is determined that the approach angle θ kIf the lateral velocity of obstacle B lies within the preset angle range according to the direction of travel of the obstacle B, the system adjusts the lateral velocity of obstacle B by using the previously detected lateral velocity of obstacle B and the currently detected lateral velocity of obstacle B. More precisely, the lateral velocity of obstacle B configured to calculate the time to collision is corrected as shown in the following equation. ϒspeed=α⋅ϒspeed,k+β⋅ϒspeed,k−1

[0080] Here, Y is Geschw, k a lateral velocity that is currently detected, Y Geschw, k-1 is the lateral velocity that was detected immediately before, and α and β are scaling factors.

[0081] The factors α and β can be preset such that they satisfy the equation α + β = 1.

[0082] Fig. Figure 8 is a diagram illustrating a change in a preset range according to an embodiment of the invention concepts.

[0083] Referring to Fig. 8 The collision detection unit 40 can change the previously preset area to another preset area 800 in order to exclude part of an area near vehicle A from the other preset area 800 based on the direction of travel of the obstacle B.

[0084] More precisely, if it is determined that the approach angle of obstacle B, corresponding to the direction of travel, lies within the preset angle range, the previous preset range 400 is modified to be smaller than before. Specifically, the previous preset range 400 can be modified to exclude the area longitudinally adjacent to the rear of vehicle A. That is, the previous preset range 400 can be modified to be defined as being a predetermined distance from vehicle A in the rearward direction and a predetermined distance laterally.

[0085] If the obstacle B is traveling behind vehicle A and is at a short distance from vehicle A, and the main reflection point is also moving, it is accordingly determined that there is no possibility of a collision.

[0086] The system further includes a notification display unit 60, which provides the driver with a notification when the collision detection unit 40 detects a possibility of collision with obstacle B. The notification display unit 60 can provide a notification visually, tactilely, by vibration, etc., using a device such as an instrument cluster, an audio, video and navigation device (AVN), or the like.

[0087] The notification display unit 60 detects whether vehicle A is in reverse gear (R-gear). Only when vehicle A is in reverse gear does the notification display unit 60 send a notification to the driver.

[0088] In another embodiment, the obstacle detection unit 20, the direction estimation unit 30, or the collision determination unit 40 determines whether the vehicle A is in reverse gear. Only when the vehicle is in reverse gear is the obstacle B detected, its direction estimated, or the possibility of a collision determined.

[0089] Although a particular embodiment of the invention concepts has been disclosed for illustrative purposes, it is evident to the person skilled in the art that numerous different modifications, additions and substitutions are possible without departing from the technical idea of ​​the disclosure as defined in the attached claims.

Claims

[1] System designed to avoid a rear-cross traffic collision, wherein the system comprises: an obstacle detection unit (20) which detects the position of an obstacle (B) by receiving electromagnetic waves reflected from a reflection point of the obstacle (B); a direction estimation unit (30) which estimates the direction of travel of the obstacle (B) based on the position of the obstacle (B) detected by the obstacle detection unit (10); and a collision determination unit (B) which determines the possibility of a collision with the obstacle (B) on the basis of the direction of travel of the obstacle (B) estimated by the direction estimation unit (30), characterized by a reliability evaluation unit (50) which collects the multiple directions of travel of the obstacle (B) estimated by the direction estimation unit (30) and evaluates an estimated reliability degree for the direction of travel of the obstacle (B) by using the number of directions of travel collected and a variance or standard deviation between the directions of travel collected, wherein, if the reliability level estimated by the reliability evaluation unit (50) is equal to or greater than a preset reliability level, the collision determination unit (40) determines the possibility of a collision with the obstacle (B) on the basis of the direction of travel of the obstacle (B). [2] System according to claim 1, wherein the obstacle detection unit (20) is connected to a radar sensor (10) provided at each of the opposite rear ends of a vehicle (A) and detects the position of the obstacle (B) located behind or beside the vehicle (A). [3] System according to claim 1, wherein the direction estimation unit (30) collects the multiple positions of the obstacle (B) which were detected by the obstacle detection unit (20) and uses the multiple collected positions of the obstacle (B) to calculate a ratio between a change in a longitudinal direction position of the obstacle (B) and a change in a lateral direction position of the obstacle (B), thereby estimating the direction of travel of the obstacle (B). [4] System according to claim 3, wherein the direction estimation unit (30) calculates the ratio between the change in the longitudinal direction position and the change in the lateral direction position that occur between a first detected initial position of the obstacle (B) and a current position, thereby determining the direction of travel of the obstacle (B) in real time. [5] System according to claim 1, wherein, when an approach angle between the estimated direction of travel of the obstacle (B) and a side axis of a vehicle (A) lies within a preset angular range, the collision detection unit (40) determines that there is no possibility of a collision with the obstacle (B). [6] System according to claim 5, wherein the obstacle detection unit (20) calculates a lateral distance of the vehicle (A) to the obstacle (B) or a lateral speed of the obstacle (B) by using the detected position of the obstacle (B), and if the amount of change in the lateral distance to the obstacle (B) or the lateral speed of the obstacle (B) is equal to or less than a preset amount of change, the collision determination unit determines that there is no possibility of a collision with the obstacle (B). [7] System according to claim 1, wherein the obstacle detection unit (20) calculates a lateral distance of a vehicle (A) from the obstacle (B) and a lateral speed of the obstacle (B) using the detected position of the obstacle (B), and the collision determination unit (40) calculates the time until collision based on the calculated lateral distance and the calculated lateral speed and determines that there is a possibility of collision with the obstacle (B) if the obstacle (B) is within a preset range (400) and the time until collision is equal to or shorter than a preset time. [8] System according to claim 7, wherein the collision detection unit (40) sets the lateral speed of the obstacle (B) using the previously detected lateral speed of the obstacle (B) and the currently detected lateral speed of the obstacle (B) on the basis of the direction of travel of the obstacle (B). [9] System according to claim 7, wherein the collision detection unit (20) modifies the preset area (400) to exclude a part of an area adjacent to the vehicle (A) from the preset area (400) on the basis of the direction of travel of the obstacle (B). [10] System according to claim 1, further comprising: a notification display unit (60) which displays a notification to a driver of a vehicle (A) when there is a possibility of a collision with the obstacle (B) as determined by the collision detection unit (40). [11] Method for avoiding a rear-end cross-traffic collision, wherein the method comprises: the reception of electromagnetic waves reflected from a reflection point of an obstacle (B) by a vehicle (A) and the detection of the position of the obstacle (B); estimating the direction of travel of the obstacle (B) based on the detected position of the obstacle (B); and Determining the possibility of a collision with the obstacle (B) based on the detected position of the obstacle (B) or the estimated direction of travel of the obstacle (B) characterized by collecting the estimated multiple directions of travel of the obstacle (B) and evaluating an estimated reliability grade for the direction of travel of the obstacle (B) by using the number of directions of travel collected and a variance or standard deviation between the directions of travel collected, where, if the estimated reliability level is equal to or greater than a preset reliability level, the possibility of a collision with the obstacle (B) is determined on the basis of the direction of travel of the obstacle (B). [12] Method according to claim 11, wherein, when estimating the direction of travel of the obstacle (B), the multiple detected positions of the obstacle (B) are collected and the multiple collected positions of the obstacle (B) are used to calculate a ratio between a change in a longitudinal direction position of the obstacle (B) and a change in a lateral direction position of the obstacle (B), thereby estimating the direction of travel of the obstacle (B). [13] Method according to claim 11, in which, when determining the possibility of a collision with the obstacle (B), it is determined that if an approach angle between the estimated direction of travel of the obstacle (B) and a side axis of a vehicle (A) lies within a preset angular range, there is no possibility of a collision with the obstacle (B). [14] Method according to claim 11, wherein, upon detection of the position of the obstacle (B), a lateral distance of the vehicle (A) to the obstacle (B) and a lateral speed of the obstacle (B) are calculated using the detected position of the obstacle (B), and, upon determination of the possibility of a collision with the obstacle (B), the time until the collision is calculated on the basis of the calculated lateral distance and the calculated lateral speed, and if the obstacle (B) is within a preset area and the time until the collision is equal to or less than a preset time, it is determined that there is a possibility of a collision with the obstacle (B).

Images