Autonomous emergency braking system and method

Abstract

This disclosure relates to autonomous emergency braking systems and methods. More specifically, the autonomous emergency braking system according to this disclosure includes: sensors including a gravity sensor for detecting the force of gravity applied to the vehicle and a vehicle speed sensor for detecting the vehicle speed; a tilt determiner for determining the tilt of the road surface on which the vehicle is traveling based on the vehicle speed and the force of gravity; and a controller for adjusting the AEB warning time based on the determined tilt of the road surface.

Description

Technical Field

[0001] The implementation methods involve autonomous emergency braking systems and methods. Background Technology

[0002] With the rapid development of electronic control technology, various devices that were previously operated mechanically are now being driven electronically in vehicles for the convenience of drivers and the safety of operation. As a result, vehicle systems have become more complex and up-to-date.

[0003] As an example, the autonomous emergency braking (AEB) system is known to have a significant impact on avoiding rear-end accidents or collisions with pedestrians or mitigating damage.

[0004] Traditional AEB systems primarily assume flat terrain, making it difficult to accurately determine the vehicle's braking distance. Furthermore, if there are objects such as vehicles ahead, it is difficult to determine the distance to the objects using only camera sensors, resulting in difficulties in executing countermeasures. Summary of the Invention

[0005] In this context, this disclosure provides an autonomous emergency braking system and method for determining the inclination of a sloping road on which the vehicle is traveling and adjusting the AEB warning time accordingly.

[0006] To address the aforementioned problem, according to one aspect of this disclosure, an autonomous emergency braking system is provided, the autonomous emergency braking system comprising: a sensor including a gravity sensor for detecting the weight applied to the vehicle and a vehicle speed sensor for detecting the vehicle speed; a tilt determiner for determining the tilt of the road surface on which the vehicle is traveling based on the vehicle speed and the weight; and a controller for adjusting the AEB warning time based on the determined tilt of the road surface.

[0007] According to another aspect of this disclosure, an autonomous emergency braking method is provided, the autonomous emergency braking method comprising the steps of: detecting a gravity applied to the vehicle and detecting the vehicle speed; determining the inclination of the road surface on which the vehicle is traveling based on the vehicle speed and the gravity; and adjusting the AEB warning time based on the determined inclination of the road surface.

[0008] In the autonomous emergency braking system and method according to this disclosure, the inclination of the inclined road on which the vehicle is traveling is determined, and the AEB warning time is adjusted to suit the determined inclination, thereby ensuring an effective braking distance. Attached Figure Description

[0009] Figure 1This is a diagram illustrating a camera sensor and a radar sensor, according to one embodiment, for detecting objects on an inclined road and determining distances.

[0010] Figure 2 This is a block diagram illustrating an autonomous emergency braking system according to one embodiment of the present disclosure.

[0011] Figure 3 This is a diagram showing the stopping distance adjusted according to the AEB warning time according to one embodiment.

[0012] Figure 4 This is a flowchart illustrating an autonomous emergency braking method according to one embodiment of the present disclosure.

[0013] Figure 5 This is a flowchart illustrating step S430 according to one embodiment in more detail.

[0014] List of reference numerals

[0015] 10: Autonomous Emergency Braking System

[0016] 110: Sensors

[0017] 120: Tilt Determiner

[0018] 130: Controller Detailed Implementation

[0019] In the following description of examples or embodiments of this disclosure, reference will be made to the accompanying drawings, in which specific examples or embodiments that may be implemented are illustrated by way of illustration, and wherein the same reference numerals and symbols may be used to indicate the same or similar components even when the same reference numerals and symbols are shown in different drawings. Furthermore, in the following description of examples or embodiments of this disclosure, a detailed description of well-known functions and components incorporated herein will be omitted where it is determined that such detailed description may obscure the subject matter of some embodiments of this disclosure. Terms used herein, such as “comprising,” “having,” “containing,” “constituting,” “composed of,” and “formed from,” are generally intended to allow for the addition of other components unless the term is used in conjunction with the term “only.” As used herein, the singular form is intended to include the plural form unless the context clearly indicates otherwise.

[0020] This document may use terms such as “first,” “second,” “A,” “B,” “(A),” or “(B)” to describe the elements of this disclosure. Each of these terms is not used to define the nature, order, sequence, or number of elements, but merely to distinguish the corresponding element from the others.

[0021] When referring to a first element as "connected to or linked to," "in contact with," or "overlapping" with a second element, it should be interpreted as meaning that not only can the first element be "directly connected to or linked to" or "directly in contact with or overlapping" the second element, but a third element can also be "inserted" between the first and second elements, or the first and second elements can be "connected to or linked to," "in contact with," or "overlapping" with each other via a fourth element. Here, the second element can be included in at least one of two or more elements that are "connected to or linked to," "in contact with," or "overlapping" with each other.

[0022] When time-related terms such as “after,” “follow,” “next,” “before,” etc., are used to describe a process or operation of an element or configuration, or a flow or step in an operation, processing, or manufacturing method, these terms may be used to describe a discontinuous or non-sequential process or operation, unless the terms “direct” or “immediate” are used together.

[0023] Furthermore, when referring to any size, relative size, etc., the numerical value or corresponding information of the component or feature (e.g., level, range, etc.) should be considered, including tolerances or error ranges that may be caused by various factors (e.g., process factors, internal or external shocks, noise, etc.), even if no relevant description is specified. In addition, the term "may" fully encompasses all the meanings of the term "able to".

[0024] A typical autonomous emergency braking (AEB) system can detect objects using camera sensors, determine the likelihood of a collision between the object and the vehicle, and, if it determines that the object and the vehicle will collide, output an AEB warning and execute control accordingly.

[0025] Because camera sensors are used to determine distance, AEB (Automatic Emergency Braking) can be activated even if the distance to an object is short or long, if the camera sensor incorrectly detects the distance. Repeated occurrences of this can make driving inconvenient and potentially lead to accidents.

[0026] Figure 1 This indicates the distance obtained by detecting objects using camera sensors and radar sensors mounted on a vehicle on an inclined road. (See reference) Figure 1 The camera sensor identifies the distance to the object (target) as shorter than the distance identified by the radar sensor on the inclined road. The distance in the longitudinal direction detected by the radar sensor is highly reliable, and therefore, if the distance detected by the radar sensor is assumed to be the actual distance, the camera sensor will identify the object as closer than the actual distance.

[0027] In this situation, as mentioned above, it could lead to driving inconvenience and accidents.

[0028] In order to solve the above problems, an autonomous emergency braking system 10 according to one embodiment of the present disclosure will be described below with reference to the accompanying drawings.

[0029] Figure 1 This is a block diagram illustrating an autonomous emergency braking system 10 according to one embodiment of the present disclosure.

[0030] See Figure 1 According to one embodiment of the present disclosure, the autonomous emergency braking system 10 may include a sensor 110, a tilt determiner 120, a controller 130, etc.

[0031] According to one embodiment of this disclosure, the autonomous emergency braking system 10 can be an advanced driver assistance system (ADAS) installed in the vehicle 20, providing information to assist the driving of the vehicle 20 and assisting the driver control of the vehicle 20. Here, the vehicle 20 can refer to a vehicle having a motor mounted thereon and manufactured to move on the ground by using the power of the motor to roll the wheels without using rails or track. The vehicle 20 can be an electric vehicle that uses electricity as power and obtains driving energy by using the electricity stored in the battery to rotate the motor, rather than obtaining driving energy from the combustion of fossil fuels.

[0032] The autonomous emergency braking system 10 can be applied to passenger vehicles or autonomous vehicles that have a driver who can enter and control the vehicle 20.

[0033] In addition, the autonomous emergency braking system 10 according to this disclosure can be applied to roundabouts.

[0034] Sensor 110 may include a gravity sensor for detecting the force of gravity applied to the vehicle 20 and a vehicle speed sensor for detecting the speed of the vehicle 20.

[0035] In one implementation, a gravity sensor may be used to implement electronic stability control (ESC). A vehicle speed sensor may be a wheel speed sensor that detects the wheel speeds of the vehicle 20.

[0036] The gravity sensor may include a vehicle gravity sensor, wheel gravity sensors, etc., and each sensor is used to detect the gravity applied to the vehicle 20. The vehicle speed sensor can detect the vehicle speed by detecting the rotational speed of the wheels of the vehicle 20.

[0037] The tilt determiner 120 can determine the tilt of the road surface on which the vehicle 20 is traveling based on the vehicle speed and gravity. Here, the tilt can be determined by comparing the difference between the gravity value detected by the gravity sensor and the vehicle speed detected by the vehicle speed sensor. For example, the tilt of the road surface on which the vehicle 20 is traveling can be determined by comparing the gravity value detected by the wheel gravity sensors installed on the front wheels of the vehicle 20 with the gravity value detected by the wheel gravity sensors installed on the rear wheels of the vehicle 20.

[0038] The controller 130 can adjust the AEB warning time based on the determined inclination of the road surface.

[0039] Referring to Table 1 below, the object 30 detected by the camera sensor installed on the vehicle 20 can have different detection distances depending on the tilt.

[0040] [Table 1]

[0041]

[0042] Referring to Table 1, it can be seen that the TTC error is determined to be -0.25 seconds when tilted upwards at 7 degrees, -0.05 seconds when tilted upwards at 2 degrees, and +0.04 seconds when tilted downwards at -3 degrees. In other words, if... Figure 1 As shown, the camera sensor can detect the object 30 at an upward tilt angle closer to the distance detected by the radar sensor as a reference, and the camera sensor can detect the object 30 at a downward tilt angle further away from the distance detected by the radar sensor.

[0043] Therefore, the controller 130 can adjust the AEB warning time to be further delayed as the determined slope of the road surface increases, and can adjust the AEB warning time to be further advanced as the determined slope of the road surface decreases.

[0044] The controller 130 can divide the determined slope of the road surface into one of multiple slope segments and adjust the AEB warning time corresponding to the classified segment.

[0045] For example, the controller 130 can divide the upward tilt segment into five segments by referring to Table 2 shown below.

[0046] [Table 2]

[0047]

[0048] When the determined tilt angle is 4% upward tilt, the controller 130 can determine the second segment and adjust the AEB warning time to -0.1 seconds, which corresponds to the AEB warning time for the second segment. Accordingly, the AEB braking can be delayed by -0.05 seconds.

[0049] The above segments are an example and can also be applied to downward slope, and the slope range of each segment can be set to be narrower or wider depending on its purpose.

[0050] Based on the above description, the autonomous emergency braking system 10 can perform appropriate braking by determining the tilt angle and adjusting the AEB warning time according to the tilt angle to avoid a collision between the predicted object 30 and the vehicle.

[0051] Figure 3 This is a diagram showing the stopping distance adjusted according to the AEB warning time according to one embodiment.

[0052] See Figure 3 If the probability of a collision between vehicle 20 and object 30 is equal to or higher than a threshold point, the autonomous emergency braking system 10 outputs an AEB warning and performs AEB braking. In this case, the distance from when AEB braking is performed until the vehicle comes to a stop can be denoted as 'a'. The stopping distance 'c' can represent the distance between the position where vehicle 20 stops according to AEB braking and object 30.

[0053] Here, if it is determined that the vehicle 20 is traveling on a sloping road, the controller 130 can determine the slope of the road surface and adjust the AEB warning accordingly. If the slope of the road surface is determined to be upward, the controller 130 can delay the AEB warning. Figure 3 As shown in b. Based on this, the stopping distance c can be shortened.

[0054] Referring to Table 3 below, it can be seen that by adjusting the AEB warning time according to this disclosure, as a result of delaying the AEB warning based on the upward tilt condition, the stopping distance is increased from 4.16m to 3.36m.

[0055] [Table 3]

[0056]

[0057] If the probability of object 30 colliding with vehicle 20 is equal to or higher than a threshold point, controller 130 may adjust the AEB warning time. For this purpose, sensor 110 may also include an image sensor that detects object 30 present in the vicinity of vehicle 20. Here, for example, the image sensor may be a camera sensor.

[0058] Based on the above description, in the event of a predicted collision, by determining the inclination of the road surface on which the vehicle 20 is traveling and adjusting the AEB warning time, a more accurate stopping distance can be maintained.

[0059] Such a controller 130 can be implemented by an electronic control unit (ECU), a microcomputer, etc.

[0060] In one embodiment, the controller 130 may be implemented by an electronic control unit (ECU). The ECU may include one or more processors and at least one or more elements selected from memory, storage devices, user interface inputs, and user interface outputs, and these may communicate with each other via a bus. Furthermore, the computer system may include a network interface for connecting to a network. The processor may be a CPU or a semiconductor element that executes processing commands stored in memory and / or storage locations. Memory and storage devices may include various types of volatile / non-volatile storage media. For example, memory may include ROM and RAM.

[0061] The following describes an autonomous emergency braking method using an autonomous emergency braking system 10 capable of performing all of the above disclosures.

[0062] Figure 4 This is a flowchart illustrating an autonomous emergency braking method according to one embodiment of the present disclosure.

[0063] Reference Figure 4 The autonomous emergency braking method according to this disclosure may include: a sensor detection step (S410) for detecting the gravity applied to the vehicle 20 and detecting the vehicle speed of the vehicle 20; a tilt determination step (S420) for determining the tilt of the road surface on which the vehicle 20 is traveling based on the vehicle speed and gravity of the vehicle 20; and an AEB warning time adjustment step (S430) for adjusting the AEB warning time based on the determined tilt of the road surface.

[0064] Here, the tilt angle can be determined by comparing the difference between the gravity value detected by the gravity sensor and the vehicle speed detected by the vehicle speed sensor.

[0065] In the AEB warning time adjustment step (S430), the AEB warning time can be adjusted if the probability of the object 30 colliding with the vehicle 20 is equal to or higher than a threshold point. For this purpose, in the sensor detection step (S410), the object 30 present near the vehicle 20 can be further detected.

[0066] In the AEB warning time adjustment step (S430) used for adjustment, the AEB warning time can be adjusted to be further delayed as the determined slope of the road surface increases.

[0067] In the AEB warning time adjustment step (S430) used for adjustment, the AEB warning time can be adjusted to be further advanced as the determined slope of the road surface decreases.

[0068] Figure 5 This is a flowchart illustrating step S430 according to one embodiment in more detail.

[0069] See Figure 5 The autonomous emergency braking system 10 can divide the determined incline into specific segments (S510). The autonomous emergency braking system 10 can set multiple segments, such that the AEB warning time operates based on an incline similar to flat ground. For example, such segments can be divided into the five segments shown in Table 3 above, or can be set to fewer or more segments depending on the purpose. The autonomous emergency braking system 10 can determine the AEB warning time corresponding to the specific segment (S520).

[0070] The autonomous emergency braking system 10 can associate the AEB warning time with each of the multiple segments. If the determined inclination is divided into one of the multiple segments, the autonomous emergency braking system 10 can identify the AEB warning time corresponding to the classified segment. Here, for example, the distance to the object 30 determined by a radar sensor can be used as a reference to set the AEB warning time corresponding to each segment.

[0071] The autonomous emergency braking system 10 can adjust the existing AEB warning time based on the identified AEB warning time. Then, the autonomous emergency braking system 10 can perform control such that AEB braking is performed using the adjusted AEB warning time as a reference.

[0072] As described above, according to this disclosure, the autonomous emergency braking system and method can use a camera sensor to adjust the AEB warning time so as to effectively avoid collisions with objects such as vehicles, pedestrians, bicycles and motorized bicycles based on the inclination of the road surface.

[0073] Furthermore, when the camera sensor limits the recognition distance based on tilt, this disclosure can use software to implement countermeasures. Accordingly, when the camera sensor is limited, this disclosure can restore that limitation by minimizing AEB control.

[0074] Furthermore, this disclosure can reduce incorrect warnings and controls for objects located on the side.

[0075] The above description is provided to enable those skilled in the art to implement and use the technical ideas of this disclosure, and is given in the context of a particular application and its requirements. Various modifications, additions, and substitutions to the described embodiments will be apparent to those skilled in the art, and the general principles defined herein can be applied to other embodiments and applications without departing from the spirit and scope of this disclosure. The above description and drawings provide examples of the technical ideas of this disclosure for illustrative purposes only. That is, the disclosed embodiments are intended to illustrate the scope of the technical ideas of this disclosure. Therefore, the scope of this disclosure is not limited to the embodiments shown, but is consistent with the widest scope conforming to the claims. The scope of protection of this disclosure should be interpreted based on the appended claims, and all technical ideas within the scope of their equivalents should be interpreted as being included within the scope of this disclosure.

[0076] Cross-reference to related applications

[0077] This application claims priority to Korean Patent Application No. 10-2021-0084524, filed on June 29, 2021, which is incorporated herein by reference for all purposes, as if fully set forth herein.

Claims

1. An autonomous emergency braking system comprising: a sensor including a gravity sensor that detects a gravity applied to a host vehicle, a vehicle speed sensor that detects a vehicle speed of the host vehicle, and an image sensor that detects an object present in a vicinity of the host vehicle and a distance to the object; a gradient determiner that determines a gradient of a road surface on which the host vehicle is traveling based on the vehicle speed and the gravity of the host vehicle; and a controller that adjusts an autonomous emergency braking (AEB) warning time based on the determined gradient of the road surface to reduce an incorrect warning in a case where the image sensor differently detects the distance to the object according to the determined road gradient. 2.The autonomous emergency braking system according to claim 1, in a case where a possibility that the object collides with the host vehicle is equal to or higher than a threshold point, the controller adjusts the AEB warning time. wherein the controller adjusts the AEB warning time to be further delayed as the determined gradient of the road surface becomes higher.

3. The autonomous emergency braking system of claim 1, wherein, the controller adjusts the AEB warning time to be further advanced as the determined gradient of the road surface becomes lower.

4. The autonomous emergency braking system of claim 1, wherein, the controller divides the determined gradient of the road surface into one of a plurality of gradient sections, and adjusts the AEB warning time corresponding to the classified section.

5. The autonomous emergency braking system of claim 1, wherein, the gradient is determined by comparing a difference between a value of the gravity detected by the gravity sensor and the vehicle speed detected by the vehicle speed sensor.

6. The autonomous emergency braking system of claim 1, wherein, 7.An autonomous emergency braking method comprising the steps of: detecting a gravity applied to a host vehicle, detecting a vehicle speed of the host vehicle, and detecting an object present in a vicinity of the host vehicle and a distance to the object by an image sensor; determining a gradient of a road surface on which the host vehicle is traveling based on the vehicle speed and the gravity of the host vehicle; and adjusting an autonomous emergency braking (AEB) warning time based on the determined gradient of the road surface to reduce an incorrect warning in a case where the image sensor differently detects the distance to the object according to the determined road gradient. 8.The autonomous emergency braking method according to claim 7, in the step of adjusting an AEB warning time, in a case where a possibility that the object collides with the host vehicle is equal to or higher than a threshold point, the AEB warning time is adjusted. in the step of adjusting an AEB warning time, the AEB warning time is adjusted to be further delayed as the determined gradient of the road surface becomes higher. wherein in the step of adjusting an AEB warning time, the AEB warning time is adjusted to be further advanced as the determined gradient of the road surface becomes lower.

9. The autonomous emergency braking method of claim 7, wherein, in the step of adjusting an AEB warning time, the determined gradient of the road surface is divided into one of a plurality of gradient sections, and the AEB warning time corresponding to the classified section is adjusted.

10. The autonomous emergency braking method of claim 7, wherein, ​ 11. The autonomous emergency braking method of claim 7, wherein, ​ 12. The autonomous emergency braking method of claim 7, wherein, The inclination is determined by comparing the value of the gravity detected by the gravity sensor with the difference of the vehicle speed detected by the vehicle speed sensor.

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