KR102373334B1 - Apparatus and method for controlling speed in cacc system - Google Patents

Abstract

The present invention relates to an apparatus and method for controlling the speed of a vehicle based on information on a plurality of preceding vehicles traveling in the same lane acquired using V2X (Vehicle to Everything) communication, and is provided in the disclosed own vehicle A cooperative adaptive cruise control (CACC) system that controls the driving speed of a vehicle uses a communication unit that receives vehicle information including location and driving information from nearby vehicles, and sensors provided in the own vehicle. An information collection unit that collects vehicle information of a vehicle and vehicle information of the own vehicle, a preceding vehicle and a preceding vehicle are determined using sensors provided in the own vehicle, and vehicle information and communication unit of the preceding vehicle and the preceding vehicle Based on the vehicle information of surrounding vehicles obtained in and a controller configured to control the traveling speed of the host vehicle based on speed information of the first target vehicle and the second target vehicle.
The present invention can provide a safe driving environment to the driver by determining the driving speed of the own vehicle using the driving information of the first target vehicle and the second target vehicle.

Description

APPARATUS AND METHOD FOR CONTROLLING SPEED IN CACC SYSTEM

The present invention relates to a speed control apparatus and method in a cooperative adaptive cruise control (CACC) system, and more particularly, to a plurality of driving in the same lane obtained using V2X (Vehicle to Everything) communication. It relates to an apparatus and method for controlling the speed of a vehicle based on information about the preceding vehicle.

The Adaptive Cruise Control (ACC) system automatically drives at or below the speed set by the driver, but maintains the vehicle-to-vehicle distance from the target vehicle to a certain distance or more. It provides a tracking function that maintains a distance that can prevent a collision with a target vehicle in front obtained by a position measurement sensor, or provides a cruise function that automatically travels at a speed set by the driver.

This CACC system has the convenience that the driver does not need to continuously operate the accelerator to control the vehicle's driving speed, maintains a certain distance from the target vehicle, and prevents the vehicle from traveling over the set speed to ensure safe driving. can be oriented

On the other hand, the CACC system is a system that improves ACC performance by adding V2X communication to the above-described ACC system. After receiving the information about the driving target vehicle, ACC performance can be improved based on this.

However, the conventional CACC system sets the preceding vehicle immediately in front of the own vehicle as the target vehicle and then adjusts the speed of the own vehicle based on the speed of the target vehicle. .

The present invention provides a CACC system for determining a driving speed based on driving information of a preceding vehicle and the preceding vehicle and a control method thereof.

In order to achieve the above object, a cooperative adaptive cruise control (CACC) system provided in the own vehicle and controlling the traveling speed of the own vehicle according to the present invention for achieving the above object is a vehicle including location and driving information from surrounding vehicles. A communication unit that receives information, an information collection unit that collects vehicle information of surrounding vehicles and vehicle information of the own vehicle using sensors provided in the own vehicle, and a preceding vehicle and a preceding vehicle using sensors provided in the own vehicle The target vehicle (hereinafter, the first target vehicle) and the target vehicle to be followed by the host vehicle based on vehicle information of the preceding vehicle and the preceding vehicle and vehicle information of surrounding vehicles obtained from the communication unit The control unit may include a control unit that selects a target vehicle (hereinafter, referred to as a second target vehicle) and controls the traveling speed of the host vehicle based on the selected speed information of the first target vehicle and the second target vehicle. In addition, the CACC system may further include a driving unit for controlling a throttle and a brake and/or a DVI unit for notifying the driver of status information of the cooperative adaptive cruise control system, wherein the control unit is the driving speed of the host vehicle to control the driving unit.

In more detail, the control unit determines a preceding vehicle and a preceding vehicle using a state management unit that manages the state of the cooperative adaptive cruise control system, and sensors provided in the own vehicle, and determines the preceding vehicle and the preceding vehicle. Selecting a target vehicle to be followed by the own vehicle (hereinafter referred to as a first target vehicle) and a target vehicle to be followed by the target vehicle (hereinafter referred to as a second target vehicle) based on vehicle information and vehicle information of surrounding vehicles obtained from the communication unit and a target vehicle selection unit, and a driving management unit controlling the traveling speed of the host vehicle based on the selected speed information of the first target vehicle and the second target vehicle, wherein the state management unit is a cooperative adaptive cruise control system This is an OFF state that does not operate, a standby state that operates but does not control the traveling speed of the own vehicle, and there is no vehicle in the region of interest connected by V2V communication. There is an ACC active state that controls the driving speed of the vehicle, and there is a surrounding vehicle in the region of interest connected through V2V communication. The state of the cooperative adaptive cruise control system is displayed as one of the cooperative active states for controlling the traveling speed of the own vehicle, the information collection unit includes a distance sensor for detecting an object in front, and the target vehicle selection unit detects the distance sensor Based on the result, it is possible to determine the existence of a preceding vehicle and a preceding vehicle traveling in the same lane as the driving lane of the host vehicle.

And, the target vehicle selector determines, as the preceding vehicle, an object on the driving lane of the host vehicle having a width equal to or greater than a predetermined first reference width according to the detection result of the distance sensor, or a curvature of the driving lane of the host vehicle If less than this predetermined reference curvature, it is determined that an object having a width equal to or greater than the second reference width for a predetermined reference time is the preceding vehicle, or among objects having a width greater than or equal to the second reference width for the reference time An object whose width increases may be determined as the preceding vehicle. In addition, the target vehicle selector may obtain the second reference width based on the distance to the front object and the position of the preceding vehicle, and if the curvature of the driving lane is greater than or equal to a predetermined reference curvature, When a plurality of surfaces are detected by the sensor and an object having a width greater than or equal to the second reference width is determined as the preceding vehicle, or a plurality of objects having a width greater than or equal to the second reference width are detected by the distance sensor, the An object closest to the preceding vehicle may be determined as the preceding vehicle.

The driving management unit may control the host vehicle to travel according to any one of a first driving speed corresponding to the driving information of the first target vehicle and a second driving speed corresponding to the driving information of the second target vehicle. Or, the host vehicle can be controlled to travel according to a smaller value of the first traveling speed and the second traveling speed, or when the curvature of the traveling lane of the host vehicle is smaller than a predetermined first reference curvature, When the first target vehicle departs from the driving lane of the host vehicle, the host vehicle may be controlled to travel at a driving speed determined according to driving information of the first target vehicle and the second target vehicle. In addition, whether the first target vehicle departs from the driving lane of the host vehicle may be determined using the speed and position of the first target vehicle obtained from the detection result of the distance sensor.

Here, the distance sensor may include a lidar.

In addition, the information collection unit may further include a camera for acquiring a front image, and the target vehicle selector may acquire information on a lane in which the own vehicle is traveling from the front image acquired by the camera.

In order to achieve the above object, the speed control method of a cooperative adaptive cruise control (CACC) system provided in the own vehicle and controlling the traveling speed of the own vehicle according to the present invention for achieving the above object is a speed control method of a surrounding vehicle using V2V communication. obtaining vehicle information; determining a preceding vehicle and a preceding vehicle by using a sensor of the own vehicle; comparing vehicle information of the surrounding vehicle with vehicle information of the preceding vehicle and preceding vehicle to obtain a first target vehicle and determining a second target vehicle; determining a traveling speed of the host vehicle using traveling information of the first target vehicle and the second target vehicle; and controlling the host vehicle according to the determined traveling speed may include steps.

In more detail, the step of determining the preceding vehicle and the preceding vehicle using the sensor of the own vehicle is a step of detecting a front object, and based on the detection result, driving in the same lane as the driving lane of the own vehicle Determining the preceding vehicle, and determining the preceding vehicle by using the determined position of the preceding vehicle, and further determining the preceding vehicle may include determining the preceding vehicle according to the detection result according to the detection result. An object on the driving lane of the host vehicle having a width greater than or equal to the reference width is determined as the preceding vehicle, or an object on the driving lane of the host vehicle having a width greater than or equal to a second reference width obtained by the location of the preceding vehicle is selected as the line If it is determined as the preceding vehicle or the curvature of the driving lane is less than a predetermined reference curvature, an object having a width greater than or equal to the second reference width for a predetermined reference time is determined as the preceding vehicle, or the second reference width determining an object whose width increases during the reference time among objects having a width greater than or equal to the preceding vehicle as the preceding vehicle, or obtaining the second reference width based on the distance to the preceding object and the position of the preceding vehicle; and determining, as the preceding vehicle, an object on the driving lane of the host vehicle having a width equal to or greater than the obtained second reference width, or if the curvature of the driving lane is equal to or greater than a predetermined reference curvature, a plurality of surfaces When an object having a width greater than or equal to the second reference width is detected as the preceding vehicle, or a plurality of objects having a width greater than or equal to the second reference width are detected, the object closest to the preceding vehicle is selected as the preceding vehicle can be determined as

and the determining of the driving speed of the host vehicle using the driving information of the first target vehicle and the second target vehicle includes: acquiring a first driving speed corresponding to the driving information of the first target vehicle; Obtaining a second driving speed corresponding to the driving information of a second target vehicle, and determining the driving speed of the host vehicle according to any one of the first driving speed and the second driving speed In addition, the step of determining the traveling speed of the host vehicle according to any one of the first traveling speed and the second traveling speed may include setting a smaller value of the first traveling speed and the second traveling speed of the host vehicle. It may be a step of determining the driving speed.

In addition, the determining of the driving speed of the host vehicle by using the driving information of the first target vehicle and the second target vehicle may include: when a curvature of a lane on which the host vehicle travels is smaller than a predetermined first reference curvature, determining whether the first target vehicle deviates from the lane on which the host vehicle travels; and if it is determined that the first target vehicle departs from the lane on which the host vehicle travels, the first target vehicle and the second target vehicle The method may include determining the driving speed of the host vehicle by using the driving information of the target vehicle, and in addition, determining whether the first target vehicle departs from the lane in which the host vehicle travels may include: The method may include determining whether the first target vehicle departs from a lane in which the host vehicle travels by using the speed and location of the target vehicle.

And the step of detecting the distance to the front object includes detecting the distance to the front object using a lidar, and determining a preceding vehicle and a preceding vehicle using a sensor of the own vehicle The doing may further include acquiring a front image and determining a driving lane of the own vehicle from the front image.

According to the present invention, in performing the CACC system, by determining the driving speed of the host vehicle using the driving information of the first target vehicle and the second target vehicle, driving safety can be further increased, and in particular, 2 When the target vehicle drives at a low speed, even when the first target vehicle suddenly changes lanes, the driving speed is determined according to the driving information of the second target vehicle, thereby providing a safe driving environment to the driver.

1 is an exemplary diagram of a CACC system 300 to which the present invention is applied.
2 is a diagram illustrating a region of interest (ROI) of the CACC system 300 on a straight road.
3 is a block diagram of a CACC system 300 according to an embodiment of the present invention.
4 is a diagram illustrating a state transition diagram of the CACC system 300 according to an embodiment of the present invention.
5 is a view for explaining a driving speed control process of the CACC system 300 according to an embodiment of the present invention.
6A and 6B are diagrams for explaining the detection results of the preceding vehicle Cp1 and the preceding vehicle Cp2 according to the position of the preceding vehicle Cp1.
7 is a diagram illustrating a case in which the preceding vehicle Cp1 is changing into a right lane.
8 is a view for explaining the detection result of the preceding vehicle and the preceding vehicle according to the position of the preceding vehicle with respect to a curved driving lane.
9 is a flowchart for controlling the traveling speed of the host vehicle in the CACC system 300 according to an embodiment of the present invention.
10 is a flowchart of determining a preceding vehicle and a preceding vehicle by using a sensor of the own vehicle in the CACC system 300 according to an embodiment of the present invention.
11 is a flowchart of determining a preceding vehicle and a preceding vehicle by using a sensor of the own vehicle in the CACC system 300 for a straight driving lane according to an embodiment of the present invention.
12 is a flowchart of determining a preceding vehicle and a preceding vehicle by using a sensor of the own vehicle in the CACC system 300 for a curved driving lane according to an embodiment of the present invention.

In order to clearly explain the present invention, parts irrelevant to the description are omitted, and the same reference numerals are assigned to the same or similar components throughout the specification.

Throughout the specification, when a part is "connected" with another part, this includes not only the case of being "directly connected" but also the case of being "electrically connected" with another element interposed therebetween. . In addition, when a part "includes" a certain component, this means that other components may be further included rather than excluding other components unless otherwise stated.

When a part is referred to as being “above” another part, it may be directly on the other part, or the other part may be involved in between. In contrast, when a part refers to being "directly above" another part, no other part is involved in between.

The terms first, second and third etc. are used to describe, but are not limited to, various parts, components, regions, layers and/or sections. These terms are used only to distinguish one part, component, region, layer or section from another part, component, region, layer or section. Accordingly, a first part, component, region, layer or section described below may be referred to as a second part, component, region, layer or section without departing from the scope of the present invention.

The terminology used herein is for the purpose of referring to specific embodiments only, and is not intended to limit the present invention. As used herein, the singular forms also include the plural forms unless the phrases clearly indicate the opposite. The meaning of "comprising," as used herein, specifies a particular characteristic, region, integer, step, operation, element and/or component, and includes the presence or absence of another characteristic, region, integer, step, operation, element and/or component. It does not exclude additions.

Terms indicating a relative space such as “below” and “above” may be used to more easily describe the relationship of one part shown in the drawing to another part. These terms, along with their intended meanings in the drawings, are intended to include other meanings or operations of the device in use. For example, if the device in the drawings is turned over, some parts described as being "below" other parts are described as being "above" other parts. Thus, the exemplary term “down” includes both the up and down directions. The device may be rotated 90 degrees or at other angles, and terms denoting relative space are to be interpreted accordingly.

Although not defined otherwise, all terms including technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the art to which the present invention belongs. Commonly used terms defined in the dictionary are additionally interpreted as having a meaning consistent with the related technical literature and the presently disclosed content, and unless defined, are not interpreted in an ideal or very formal meaning.

Hereinafter, with reference to the accompanying drawings, the embodiments of the present invention will be described in detail so that those of ordinary skill in the art can easily carry out the present invention. However, the present invention may be implemented in several different forms and is not limited to the embodiments described herein.

First, terms that can be used in this specification are defined.

Forward vehicle: A vehicle in front of the own vehicle moving in the same direction along the same road as the own vehicle.

Far-forward vehicle: A vehicle in front of the preceding vehicle while moving in the same direction along the same road as the own vehicle and the preceding vehicle.

Clearance: The distance between the end of the preceding vehicle and the front of the own vehicle.

Region of Interest: A region in which a potential vehicle of interest and a target vehicle, which will be described later, exist, and may affect the control of the CACC system provided in the own vehicle.

Potential Vehicle of Interest: A vehicle that exists in an area of interest and performs V2V communication with its own vehicle.

Target Vehicle: A vehicle that the own vehicle follows, which may or may not be connected to the own vehicle through V2V communication.

Time gap: A value calculated by the speed of the own vehicle and the distance from the preceding vehicle. Time Gap = Interval/Speed

Hereinafter, preferred embodiments according to the present invention will be described in detail with reference to the accompanying drawings.

1 is an exemplary diagram of a CACC system to which the present invention is applied.

As shown in FIG. 1, the CACC system 300 applied to the present invention adds a wireless communication function with front vehicles and/or infrastructure in order to enhance the sensing capability of the conventional ACC system. is a system that has been The CACC system 300 may receive, from a Road-Side Equipment (RSE) 10 using V2I communication, the speed limit of the road, a time gap (Time Gap; a time difference with the vehicle in front), and other standard messages. there is. That is, the CACC system 300 of the vehicle may receive information such as a recommended set speed or a time gap from the local traffic control system through V2I communication. In addition, the CACC system 300 receives surrounding vehicle information including driving information (speed and acceleration) of the surrounding vehicle 20 through V2V communication with at least one or more surrounding vehicles 20 or transmits its own vehicle information to the surrounding area. It can be transmitted to the vehicle 20 . In addition, it is possible to obtain vehicle information that may exist in the front using conventional sensors.

At this time, the driving vehicle information includes vehicle identification (ID) that can be distinguished from other vehicles, vehicle type, size, brake performance, vehicle finances including total vehicle weight, latitude, longitude, and altitude of the vehicle displayed in three dimensions. It may include a position, a traveling angle of the vehicle measured based on a true north direction, a vehicle speed, an acceleration, a yaw rate, a brake state, a throttle position, a steering angle, and the like.

In addition, the CACC system 300 may receive a set speed or a time gap from the driver through a Driver Vehicle Interface (DVI) 60 , and inform the driver of state information of the CACC system 300 . Also, the CACC system 300 may acquire vehicle information 50 from various sensors or control devices inside the vehicle. Thus, the CACC system 300 may control the speed of the vehicle by controlling the throttle or brake based on the various data collected in the above-described manner.

As such, by acquiring information through V2V communication and/or V2I communication, the CACC system 300 can more accurately control the time gap with the vehicle in front while maintaining a smooth ride, and respond to speed changes by a plurality of vehicles in front. It can respond much faster and has the advantage of being able to set shorter time gaps without compromising safety or driver stability.

2 is a diagram illustrating a region of interest (ROI) of the CACC system 300 on a straight road.

The CACC system 300 may be interested only in the surrounding vehicles entering the region of interest. Information coming from a vehicle outside the region of interest may be information that has little meaning in controlling the vehicle. Accordingly, the load applied to the CACC system 300 can be reduced by controlling only the information from the vehicle within the region of interest.

Referring to FIG. 2 , the region of interest has a length of 32 m each 16 m to the left and right with respect to the center of the vehicle equipped with the CACC system 300, and can be set to 250 m in front of the driver's seat and 100 m in the rear. there is. In the case of a curved road, the region of interest set in the straight road may be bent to match the curvature of the curved road and may be set.

In addition, the CACC system 300 may set a target vehicle and a potential vehicle of interest (PVOI). The target vehicle refers to a vehicle in front that is followed by the own vehicle equipped with the CACC system 300 . That is, the CACC system 300 uses the distance maintained with the target vehicle when calculating the time gap, and the target maintaining the time gap is also the target vehicle. The potential vehicle of interest refers to a vehicle connected to the CACC system 300 through V2V communication while being in the area of interest. A potential vehicle of interest may be a vehicle capable of affecting the speed control of the own vehicle equipped with the CACC system 300 . Vehicles expected to merge into the own vehicle's lane from the next lane, the own vehicle and the vehicle in the same lane as the target vehicle and in front of the target vehicle, etc. may be potential vehicles of interest. there is.

3 is a block diagram of a CACC system 300 according to an embodiment of the present invention.

Referring to FIG. 3 , the CACC system 300 according to the present invention may include an information collection unit 310 , a communication unit 320 , a DVI unit 340 and a control unit 330 , and the control unit 330 is a state The management unit 331 may include a driving management unit 333 and a target vehicle selection unit 335 .

The communication unit 320 may receive a speed limit of a road, a time gap (time difference from a vehicle in front), and other standard messages from the RSE 10 based on V2I communication. That is, the CACC system 300 of the vehicle may receive information on road, traffic, weather, and life as well as set speed or time gap information recommended from the local traffic control system through V2I communication. In addition, the communication unit 320 receives surrounding vehicle information including driving information (speed and acceleration) of the surrounding vehicle 20 through V2V communication with at least one or more surrounding vehicles 20 or transmits its own vehicle information to the surrounding vehicle ( 20) can be forwarded. In particular, in this case, it is possible to provide not only own driving information of the surrounding vehicle 20 but also identifier information or driving information of its preceding vehicle. When the surrounding vehicle provides only the identifier information, vehicle information on the preceding vehicle of the neighboring vehicle that has transmitted the identifier information may be obtained using information from the surrounding vehicle having such identifier information. Accordingly, the host vehicle may acquire vehicle information about the target vehicle and a vehicle preceding the target vehicle as well. On the other hand, when only identifier information is transmitted, the amount of data transmitted by each vehicle can be reduced.

In addition, the information collection unit 310 may collect the information of the own vehicle and the surrounding environment information collected using the sensor required for control of the CACC system 300 . The information of the own vehicle may include driving speed, throttle, brake control information, etc. of the own vehicle, and the surrounding environment information may include information about the surrounding vehicle 20 collected through a sensor. In particular, when a target vehicle exists in front of the own vehicle, the driving speed and separation distance of the target vehicle can be calculated based on radar, lidar, etc. and collected as surrounding environment information.

The DVI unit 340 may receive setting information input from the driver through an interface between the driver and the vehicle (Driver-Vehicle Interface), and the state information of the CACC system 300 may be generated by the CACC system 300 . Information that needs to be notified to the driver, such as warning information, can be delivered to the driver. As an example, the driver may input the target speed and/or the target time gap through the DVI unit 340 , and the CACC system 300 controls the vehicle to run according to the input target speed and/or the target time gap. can do. As another embodiment, as will be described later, state information such as whether the CACC system 300 is in an off state, in a standby state, or in an active state may be notified to the driver through the DVI unit 340 .

In addition, a driving unit (not shown) may be further included, and the driving unit may control a throttle and/or a brake according to a control signal of the driving management unit 333 of the control unit 330 to be described later.

The control unit 330 may control the traveling speed of the own vehicle based on the information obtained from the information collection unit 310 and the communication unit 320 . That is, the control unit 330 selects a target vehicle to be followed by the own vehicle based on the vehicle information of the surrounding vehicles obtained by the communication unit 320 and the driving information of the preceding vehicle collected by the information collection unit 310 , and if If the target vehicle to be followed by the own vehicle is not selected, the traveling speed of the own vehicle can be controlled based on the target speed given to the own vehicle. If the target vehicle to be followed by the own vehicle is selected, the speed of the target vehicle The driving speed of the own vehicle may be controlled based on the information, the speed information of the own vehicle, and the target time gap. At this time, the target speed and the target time gap can be set by the user, but differently from this, the CACC system 300 automatically sets the target speed and the target time gap based on the information obtained from the information collection unit 310 and the communication unit 320 . can also be set according to the situation.

The control unit 330 for performing the above-described functions may be further subdivided and include a state management unit 331 , a driving management unit 333 , and a target vehicle selection unit 335 .

The target vehicle selection unit 335 may select a potential vehicle of interest and a target vehicle based on vehicle information of a plurality of surrounding vehicles 20 coming through the communication unit 320 . A vehicle of potential interest means a nearby vehicle existing in the above-mentioned area of interest. Based on the location information received from the surrounding vehicle and the location information of the own vehicle, if a nearby vehicle is within the area of interest, it can be selected and registered as a potential vehicle of interest. . In addition, a vehicle immediately preceding the own vehicle among potential interested vehicles may be selected as the target vehicle. In particular, the target vehicle needs to be verified with very high reliability. Based on the information of the preceding vehicle collected through the following information collection unit 310, the following three conditions can be verified and selected as the target vehicle. .

1: A vehicle of potential interest (hereinafter referred to as a first potential vehicle group of potential interest) is selected using the location information of the vehicle of potential interest, which runs in the same lane as the lane of the own vehicle.

2: Existence range information received from each potential vehicle of interest in the first potential vehicle group is from the range measured by the sensor (0.1 times the range measured by the sensor) or (0.7 times the length of each potential vehicle of interest) A potential vehicle of interest (hereinafter referred to as a second potential vehicle of interest group) existing within a larger value of At this time, if the length of the potential vehicle of interest is unknown (0.7 times the length of each potential vehicle of interest), 3.3 meters can be used.

3: A potential interest vehicle (third potential interest vehicle group) with a difference between the speed information received from each potential interest vehicle in the second potential interest vehicle group and the speed measured by the sensor within 1 m/s is selected.

In general, only one vehicle of potential interest is included in the third potential vehicle of interest group selected through the verification of the three conditions, but when two or more vehicles of potential interest are included, each potential interest of the third potential vehicle of interest group is included. Based on the location information of the vehicle, a potential vehicle of interest in the nearest location may be selected as the target vehicle.

In the above-described condition verification, more accurate verification may be possible if the determination is made by comparing accumulated sample data rather than comparing one sample data.

In an embodiment, after calculating a correlation coefficient based on Equations 1 and 2 below, it is possible to determine whether or not a target vehicle is present based on this.

Here, N is the number of samples for measuring the amount of change in speed and acceleration, V _TV (N) is the speed at the Nth sample of the target vehicle calculated based on radar, and V _i (N) is the number of samples received from the surrounding vehicle (i). The speed at the Nth sample of the driving information, a _i (N) is the acceleration at the Nth sample among the driving information received from the surrounding vehicle (i), and Δt is the sample value based on the driving information received from the surrounding vehicle (i) and the time difference with the radar-based speed sample value, respectively.

Here, -1 < r < 1 is satisfied, and the closer r is to 1, the higher the correlation, and thus the target vehicle can be verified.

When the target vehicle selection unit 335 determines whether a target vehicle or a vehicle of potential interest exists, this information is transmitted to the state management unit 331 and/or the driving management unit 333 to be used according to the purpose of each function.

The state management unit 331 may manage the state of the CACC system 300 . The CACC system 300 may be in an off state, a standby state, or an active state depending on the state of the own vehicle, the presence of the target vehicle and/or the potential vehicle of interest.

4 is a diagram illustrating a state transition diagram of the CACC system 300 according to an embodiment of the present invention.

Referring to FIG. 4 , the CACC system 300 is in an OFF state 400 in which the CACC system 300 does not operate, in a standby state 500 that operates but does not control the traveling speed of the host vehicle, and It may include an active state 600 for controlling the traveling speed of the host vehicle. In particular, the active state 600 is connected through V2V communication with the ACC active state 610 that controls the traveling speed of the own vehicle using only information obtained from the own vehicle without a vehicle in the region of interest connected by V2V communication. There is a nearby vehicle in the region of interest, and a cooperative activation state 620 for controlling the traveling speed of the own vehicle using information from the surrounding vehicle acquired through the V2V communication and information obtained from the own vehicle. can

The off state 400 is a state in which the CACC system 300 is not operating. That is, in the off state 400 , the CACC system 300 does not perform any function. The ignition of the host vehicle may be turned off or may be manually transferred to the off state 400 by the driver.

The standby state 500 is a state in which the CACC system 300 is waiting to be activated. In the standby state 500 , the CACC system 300 does not perform speed control. The CACC system 300 may automatically transition from the off state 400 to the standby state 500 after completing the self-diagnosis when the ignition of the own vehicle is turned on, or manually by the driver's operation in the off state 400 ) to the standby state (200). Also, when a driver's manual control input, such as brake or throttle control, is received in the active state 600 , it may transition to the standby state 500 .

The active state 600 is a state in which the CACC system 300 is activated to perform speed control. The active state 600 operates in the ACC active state 610 when there is no potential vehicle of interest or target vehicle connected by V2V communication, and when there is a potential vehicle of interest or target vehicle connected by V2V communication, the cooperative active state ( 620) can be operated. The CACC system 300 may transition to the active state 600 when the speed of the host vehicle is higher than a predetermined speed (hereinafter, referred to as a first speed) in the standby state 500 . In addition, when the speed of the host vehicle falls below the first speed in the active state 600 , the CACC system 300 may prohibit acceleration or may transition to the standby state 500 .

When the CACC system 300 transitions to the active state 600 , it may first operate in the ACC active state 610 . In the ACC active state 610 , like the conventional ACC system, cruise control may be performed according to the set maximum speed, or following control may be performed when a vehicle is present in front. If there is a potential vehicle of interest or target vehicle connected by V2V communication in the ACC active state 610 , and data received from the potential vehicle of interest or target vehicle is valid, it may transition to the cooperative active state 620 . Here, verifying whether the data is valid is, as an embodiment, the potential vehicle of interest or target vehicle-related information received using V2V communication through the communication unit 320 by the sensor of the own vehicle received through the information collection unit 310 . If it matches the obtained vehicle information, it can be verified that the data is valid. Such verification may be performed by the target vehicle selection unit 335 .

In addition, when the potential vehicle of interest and the target vehicle do not exist in the cooperative activation state 620 , it may transition to the ACC active state 610 . Also, even when V2V communication is not performed or only invalid data is received, the ACC is activated. It may transition to state 610 .

The cooperative activation state 620 of the CACC system 300 may include a non-follow mode (621), a close-follow mode (622), and a follow mode (623). . The non-following mode 621 is a mode that operates when the potential vehicle of interest is connected through V2V communication but the target vehicle does not exist. may be affected by

The proximity tracking mode 622 is a mode that operates when there is a target vehicle connected through V2V communication, and the speed control of the own vehicle by the CACC system 300 at this time is based on information from the connected target vehicle and the potential vehicle of interest. may be affected

The following mode 330 is a mode that operates when a target vehicle exists but is not connected by V2V communication. In this case, the target vehicle can be detected by a sensor of the own vehicle, and this information is collected by the information collection unit 310 . can be obtained from At this time, the speed control of the own vehicle by the CACC system 300 may be affected by information from a connected potential vehicle of interest and a target vehicle sensed by a sensor.

The CACC system 300 can operate in one of the three modes described above in the cooperative activation state 620, and the three modes are determined by whether the target vehicle exists and whether the target vehicle is connected through V2V communication. can be determined accordingly.

That is, referring to FIG. 4 , in the cooperative activation state 620 , if the target vehicle does not exist in the region of interest, but a potential vehicle of interest exists, it transitions to the non-following mode 621 (A), and the target vehicle connected through V2V communication If there is, it transitions to the proximity tracking mode 622 (B), and when a target vehicle not connected through V2V communication exists in the ROI, and at the same time a potential vehicle of interest exists in the ROI, it goes to the following mode 623 Transition (C) is possible.

If none of the connected target vehicle and the potential vehicle of interest exist, it may transition to the ACC active state 610 .

The maximum and minimum requirements that can be controlled in the active state 600 of the CACC system 300 may be defined as shown in Table 1 below for each mode.

target vehicle Target vehicle connection PVOI presence CACC mode Ieast
time gap Maximum
Deceleration Maximum
Acceleration Whether data received through V2V communication is used no no no ACC active state: speed control mode 0.8 s 3.5 m/s^2 2.0 m/s^2 not used yes no no ACC active state: follow mode 0.8 s 3.5 m/s^2 2.0 m/s^2 not used no no yes Cooperation active:
non-following mode 0.8 s 3.5 m/s^2 2.0 m/s^2 use yes yes no Cooperation active:
close-following mode 0.5 s 5 m/s^2 2.75 m/s^2 use yes yes yes Cooperation active:
close-following mode 0.5 s 5 m/s^2 2.75 m/s^2 use yes no yes Cooperation active:
follow mode 0.8 s 3.5 m/s^2 2.0 m/s^2 use

Referring to Table 1, the CACC system 300 cannot set 0.5 s or less as the minimum time gap, control the maximum brake to control the deceleration of 5 m/s^2 or more, and control the throttle to 2.75 m/s^ Acceleration control of 2 or more cannot be performed.

Referring back to FIG. 3 , the state management unit 331 manages the state of the CACC system 300 according to the above-described method, and when the CACC system 300 is in an active state, the driving management unit 333 controls the driving speed of the own vehicle. can control In the case of the CACC system 300 , the driving speed is generally controlled so as to be driven according to the target speed set by the driver. However, when the target vehicle exists, the driving speed may be controlled so as to follow the target vehicle.

The driving management unit 333 may control the driving speed of the own vehicle based on the state information by the state management unit 331 and the presence or absence of the target vehicle and/or the potential vehicle of interest from the target vehicle selection unit 335 . In particular, in order to promote a safer driving environment for the driver, the driving speed may be controlled using not only the target vehicle of the own vehicle 700 but also the driving information of the target vehicle of the target vehicle.

Hereinafter, based on FIG. 5 , the driving control in consideration of the driving information of the target vehicle of the target vehicle in the CACC system 300 will be described in more detail.

5 is a view for explaining a driving speed control process of the CACC system 300 according to an embodiment of the present invention.

Referring to FIG. 5 , the driving line in the same lane consists of a lead vehicle Cp2 , a preceding vehicle Cp1 that may be a target vehicle of the own vehicle 700 , and the own vehicle 700 . Here, the lead vehicle Cp2 may be the target vehicle of the preceding vehicle Cp1. Here, since the vehicle Cp3 does not travel in the same lane as the own vehicle 700 , it may be a potential vehicle of interest but not a target vehicle.

The vehicles 700 , Cp1 , Cp2 , and Cp3 may exchange driving information with each other through V2V communication. In particular, each vehicle may transmit an identifier (ID) for its own target vehicle when transmitting its own driving information. That is, the vehicle Cp2 transmits only its own driving information because there is no preceding target vehicle, and if the vehicle Cp2 becomes the target vehicle of the vehicle Cp1, the vehicle Cp1 enters its own driving information. An identifier (for example, ID-2) for the target vehicle of may be transmitted together. Accordingly, the host vehicle 700 may receive identifier (eg, ID-2) information of the vehicle Cp2 that is the target vehicle of the vehicle Cp1 together with the driving information of the vehicle Cp1 that is the target vehicle. Then, the driving management unit 333 of the CACC system 300 mounted on the own vehicle 700 can know the target vehicle Cp2 of the target vehicle Cp1 using the received identifier information, and the The driving speed of the own vehicle 700 may be controlled using the driving information and the driving information received from the vehicle Cp2 .

The point to be further examined here is that the target vehicle selection unit 335 selects the data from the surrounding vehicles received from the communication unit 320 and the preceding vehicle information collected by the information collection unit 310 for accurate selection of the target vehicle. to be used together. That is, the target vehicle can be selected only when the two pieces of information match or meet the above-described verification conditions. In particular, when the speed is controlled based on the driving information of the target vehicle as well as the driving information of the target vehicle, the target vehicle of the target vehicle must be accurately identified.

Hereinafter, a method of verifying the target vehicle (the first target vehicle) of the host vehicle and the target vehicle (the second target vehicle) of the target vehicle will be described in more detail. Among the information required by the target vehicle selection unit 335 , information on surrounding vehicles received through the communication unit 320 can be obtained immediately when connected by V2V communication. The collection of information on the preceding vehicle that can be the preceding vehicle and the preceding vehicle that can be the second target vehicle will be described in more detail.

The information collection unit 310 may use a camera and/or a distance sensor 311 to collect information on the preceding vehicle and the preceding vehicle.

The camera may acquire a front image to determine the driving lane W of the own vehicle 700 . The front image acquired by the camera may include a lane W in which the own vehicle travels and a lane L forming the same. The camera may be installed on the front of the vehicle and may include an imaging sensor such as a charge coupled device (CCD) or a complementary device (CMOS).

The distance sensor 311 detects an object located in front of the own vehicle 700, for example, the preceding vehicle Cp1 and the preceding vehicle Cp2 running in front of the own vehicle 700, structures installed around the road, etc. It can detect static objects that include it, vehicles approaching from the opposite lane, and so on. Furthermore, the distance sensor 311 may detect a distance to an object in front of the own vehicle 700 , and in the case of a moving object, may sense speed and acceleration.

To this end, the distance sensor 311 may be implemented as a radar (Radar) or a lidar (Light Detection And Ranging; LiDAR). If the distance sensor 311 is implemented as a lidar, the distance sensor 311 may irradiate a laser to a predetermined area in front and receive a laser reflected from a front object. After receiving the laser, the distance sensor 311 may detect physical properties such as a distance to a front object, speed, shape, etc. from a change in reception time, intensity, frequency, and polarization state of the laser. Hereinafter, for convenience of description, it is assumed that the distance sensor 311 is implemented as a lidar.

6A and 6B are diagrams for explaining the detection results of the preceding vehicle Cp1 and the preceding vehicle Cp2 according to the position of the preceding vehicle Cp1, and the hatched area indicates that the distance sensor 311 irradiates a laser. is the area

If the preceding vehicle Cp1 and the preceding vehicle Cp2 exist on the driving lane W as shown in FIG. 5 , the distance sensor 311 of the own vehicle 700 irradiates a laser forward to the preceding vehicle (Cp1) can be detected. When the preceding vehicle Cp1 travels in the same direction as the traveling direction of the host vehicle 700 , the distance sensor 311 may detect the rear side of the preceding vehicle Cp1 . In addition, when the preceding vehicle Cp1 is located in the traveling path of the irradiated laser, the distance sensor 311 may not detect the preceding vehicle Cp2 that is obscured by the preceding vehicle Cp1.

Meanwhile, the preceding vehicle Cp1 may deviate from the driving lane W to change lanes. Referring to FIG. 6A , the preceding vehicle Cp1 may leave the driving lane W to change the lane to the right. As a result, the distance sensor 311 may detect a part of the rear of the preceding vehicle Cp1 being changed into a lane and the rear of the preceding vehicle Cp2 positioned in front of the preceding vehicle Cp1. 6A, d1 means the rear area of the preceding vehicle Cp1 detected by the distance sensor 311, and d2 is the rear area of the preceding vehicle Cp2 detected by the distance sensor 311. can

Here, d2 may vary depending on the position of the preceding vehicle Cp1. 6B illustrates a case in which the preceding vehicle Cp1 moves further to the right than in FIG. 6A . In this case, it can be seen that the rear area of the preceding vehicle Cp2 sensed by the distance sensor 311 is different from the case of FIG. 6A .

The detection result of the distance sensor 311 may be used to determine the existence of the first target vehicle Cp1 and the preceding vehicle Cp2 in the target vehicle selection unit 335 .

The target vehicle selector 335 may determine the existence of the preceding vehicle Cp1 and the preceding vehicle Cp2 traveling in the same lane as the driving lane W based on the detection result of the distance sensor 311 . As described above, since the preceding vehicle Cp1 and the preceding vehicle Cp2 must travel in the same lane as the driving lane W, first, the target vehicle selector 335 may determine the driving lane W.

To this end, the target vehicle selector 335 may use the front image obtained from the camera 200 . The target vehicle selector 335 may process the front image to clarify the lane L in the front image. Through this, the target vehicle selector 335 may extract the left and right lanes L closest to the center of the front image, and determine the lanes formed by them as the driving lane W.

When the driving lane W is determined, the target vehicle selection unit 335 determines whether an object located in the driving lane W among the front objects detected by the distance sensor 311 is the preceding vehicle Cp1 or the preceding vehicle ( Cp2) can be determined. Specifically, the target vehicle selector 335 may first determine the existence of the preceding vehicle Cp1 and then determine the existence of the preceding vehicle Cp2 using the determined position of the preceding vehicle Cp1 .

In order to determine the preceding vehicle Cp1, the target vehicle selector 335 may use a predetermined first reference width. Here, the first reference width may mean a minimum width that can be determined as the preceding vehicle Cp1 among objects detected by the distance sensor 311 . The first reference width may be stored in advance in a storage unit to be described later, or may be predetermined by a user input or operation of the target vehicle selector 335 .

If the preceding vehicle Cp1 travels in the same direction as the traveling direction of the own vehicle 700 or the traveling direction of the preceding vehicle Cp1 does not deviate significantly from the traveling direction of the own vehicle 700, the distance sensor 311 The rear side of the vehicle Cp2 may be detected. Referring to FIG. 6A , the distance sensor 311 may detect a rear area d1 of the preceding vehicle Cp1, and d1 may appear as a straight line. In this case, the length of d1 may mean the width of the preceding vehicle Cp1.

On the other hand, if the preceding vehicle Cp1 deviates significantly from the traveling direction of the host vehicle 700 , the distance sensor 311 may detect a portion of the rear and side surfaces of the preceding vehicle Cp1 . Referring to FIG. 6B , the distance sensor 311 may detect a rear region and a partial side region d1 of the preceding vehicle Cp1, and d1 may appear in an L-shape. In this case, the length of any one of the two straight lines forming the L-shaped d1 may mean the width of the preceding vehicle Cp1.

Accordingly, the target vehicle selector 335 may determine the existence of the preceding vehicle Cp1 by checking whether the width of the detected object on the driving lane W is equal to or greater than the first reference width. Specifically, the target vehicle selector 335 may determine whether the width of the detected objects in the order closest to the front is equal to or greater than the first reference width. As a result, the target vehicle selector 335 may determine the closest object from the front having a width equal to or greater than the first reference width as the preceding vehicle Cp1.

When the preceding vehicle Cp1 is determined, the target vehicle selector 335 may determine the preceding vehicle Cp2 based on the position of the preceding vehicle Cp1. As described with reference to FIGS. 6A and 6B , since the sensing area d2 of the preceding vehicle Cp2 varies according to the position of the preceding vehicle Cp1, the target vehicle selector 335 is configured according to the determined position of the preceding vehicle Cp1. The preceding vehicle Cp2 may be determined.

Specifically, the target vehicle selector 335 may determine an object having a width greater than or equal to the second reference width determined according to the position of the preceding vehicle Cp1 as the preceding vehicle Cp2 . To this end, the target vehicle selector 335 may first determine the second reference width by using the position of the preceding vehicle Cp1.

7 illustrates a case in which the preceding vehicle Cp1 is changing into a right lane, and a method of determining the second reference width will be described with reference to this. In FIG. 7 , the position of the laser-irradiated distance sensor 311 is the origin It is assumed that

First, the target vehicle selector 335 obtains the left rear corner coordinates P1 (preV_x, preV_y) of the preceding vehicle Cp1. As shown in FIG. 6A , when the sensing area d1 of the preceding vehicle Cp1 is detected as a straight line, the target vehicle selector 335 may set the left end of the straight line d1 as P1. On the other hand, as shown in FIG. 6B , when the sensing region d1 of the preceding vehicle Cp1 is sensed in an L-shape, the target vehicle selector 335 may set the vertex of d1 as P1.

Next, the target vehicle selector 335 assumes that the preceding vehicle Cp2 is located on the rightmost side on the driving lane W, and the left rear corner coordinates P2 (pre_preV_x, pre_preV_y) of the preceding vehicle Cp2 ) is obtained.

After obtaining P1 and P2, the target vehicle selector 335 may obtain an intersection P3 (intersect_x, intersect_y) between the straight line passing P1 from the origin and X=pre_preV_x.

Finally, the target vehicle selector 335 may determine the distance between P2 and P3 as the second reference width k. Specifically, the target vehicle selector 335 may acquire the second reference width k according to Equation (3).

Here, k may mean the second reference width, intersect_x may mean the x-coordinate of P3, and pre_preV_x may mean the x-coordinate of P2.

Although the description has been made on the premise that the preceding vehicle Cp1 changes lane to the right, the second reference width may be acquired in a similar manner when the preceding vehicle Cp1 changes lane to the left.

After acquiring the second reference width, the target vehicle selector 335 may determine an object having a second reference width or larger among the detected objects on the driving lane W as the preceding vehicle Cp2. The target vehicle selection unit 335 of the own vehicle 700 according to an exemplary embodiment may determine an object having a width equal to or greater than the second reference width at a point in time as the preceding vehicle Cp2.

Also, the target vehicle selection unit 335 of the own vehicle 700 according to another embodiment may determine an object maintaining a width equal to or greater than the second reference width for a predetermined reference time as the preceding vehicle Cp2. Through this, it is possible to increase the determination accuracy of the preceding vehicle Cp2.

In particular, the target vehicle selector 335 may determine an object having a width equal to or greater than the second reference width for a predetermined reference time and increasing in the sensed width as the preceding vehicle Cp2 . 6A and 6B , as the lane change of the preceding vehicle Cp1 progresses, the sensing area d2 of the preceding vehicle Cp2 may increase. Accordingly, by considering whether the width is increased, the target vehicle selector 335 can more easily determine the existence of the preceding vehicle Cp2 when the preceding vehicle Cp1 departs from the driving lane W.

In addition, when a plurality of objects having a width greater than or equal to the second reference width are detected, the target vehicle selector 335 may determine an object closest to the determined preceding vehicle Cp1 as the preceding vehicle Cp2. As described above, since the preceding vehicle Cp2 must be the target vehicle of the preceding vehicle Cp1, the target vehicle selector 335 is configured to be directly in front of the preceding vehicle Cp1 among objects having a width greater than or equal to the second reference width. It is possible to determine the object located in the preceding vehicle (Cp2).

When the preceding vehicle Cp1 and the preceding vehicle Cp2 are determined, the target vehicle selection unit 335 uses the information of the surrounding vehicle acquired through the communication unit 320 and the sensor of the own vehicle 700 as described above. If the above-described verification is passed using the collected information on the preceding vehicle Cp1 and the preceding vehicle Cp2, the reliability of the selection can be increased by determining the first target vehicle and the second target vehicle.

When the first target vehicle Cp1 and the second target vehicle Cp2 are selected by the target vehicle selection unit 335 , the driving management unit 333 controls the first target vehicle Cp1 and the second target vehicle Cp2. The driving unit may be controlled to drive at a driving speed determined according to the driving information. Here, the driving information may include all information related to driving, such as speed, acceleration, and location.

To this end, the driving management unit 333 sets the first driving speed corresponding to the driving information of the first target vehicle Cp1 and the second driving speed corresponding to the driving information of the second target vehicle Cp2 to the information collecting unit 310 . ) and/or through the communication unit 320 . Specifically, the driving management unit 333 acquires a first driving speed capable of maintaining a first safe distance with the first target vehicle Cp1 and a second driving speed capable of maintaining a second safe distance with the second target vehicle Cp2. You can get 2 driving speed.

Finally, the driving management unit 333 may control the driving unit to travel according to any one of the first driving speed and the second driving speed. Specifically, the driving management unit 333 may control the driving unit to travel according to a smaller value of the first driving speed and the second driving speed.

Through this, the CACC system 300 according to the disclosed embodiment maintains a safe distance in relation to the second target vehicle Cp2 even if the first target vehicle Cp1 leaves the lane. can be controlled.

Meanwhile, the driving management unit 333 sets the driving speed determined according to the driving information of the first target vehicle Cp1 and the second target vehicle Cp2 only when the first target vehicle Cp1 departs from the driving lane W. The driving unit may be controlled to drive. In order to determine whether the first target vehicle Cp1 departs from the driving lane W, the driving management unit 333 may use the speed and position of the first target vehicle Cp1. Specifically, the driving management unit 333 may determine whether to depart from the lane by using the speed and position of the first target vehicle Cp1 with respect to the lane L forming the driving lane W obtained through the front image. .

Through this, the host vehicle 700 according to the disclosed embodiment may determine the driving speed adaptive to whether the first target vehicle Cp1 departs from the lane.

So far, the description has been made on the assumption that the driving lane W has a straight line or a curvature similar to the straight line. Contrary to this, even when the driving lane W has a large curvature, the target vehicle selection unit 335 may similarly detect the preceding vehicle and the preceding vehicle to select the first target vehicle and the second target vehicle.

8 is a view for explaining the detection result of the preceding vehicle and the preceding vehicle according to the position of the preceding vehicle with respect to a curved driving lane.

Compared to the straight driving lane W, the own vehicle 700 driving the curved driving lane W may have a greater risk of an accident. Accordingly, when driving on the curved driving lane W, the host vehicle 700 needs to determine the driving speed in consideration of not only the driving speed of the preceding vehicle Cp1 but also the driving speed of the preceding vehicle Cp2.

When the driving lane W is determined, the target vehicle selector 335 may determine whether the curvature of the driving lane W is equal to or greater than a predetermined reference curvature. Here, the predetermined reference curvature may mean a minimum curvature of the curved driving lane W.

If the curvature of the driving lane W is equal to or greater than a predetermined reference curvature, the target vehicle selector 335 may determine the preceding vehicle Cp2 by a method corresponding to the curved driving lane W. After determining the preceding vehicle Cp1 according to the method described with reference to FIGS. 6A and 6B and FIG. 7 , the target vehicle selector 335 selects an object whose plurality of surfaces are detected by the distance sensor among objects with a second reference width or larger. It can be determined as the preceding vehicle Cp2.

Referring to FIG. 8 , when driving on the curved driving lane W, the sensing area d2 of the preceding vehicle Cp2 by the distance sensor may be formed in an L-shape. In other words, in the curved driving lane W, the distance sensor may detect the rear and one side of the second target vehicle Cp2 together.

In this way, when the target vehicle selection unit 335 detects the preceding vehicle Cp1 and the preceding vehicle Cp2 and selects the first target vehicle and the second target vehicle based on this, the driving management unit 333 is The driving speed may be determined according to the method as described above.

As such, by considering the curvature of the driving lane W, the host vehicle 700 according to the disclosed embodiment may determine a driving speed for securing a safe distance even when driving in a curved lane.

Referring back to FIG. 3 , information used to control the host vehicle 700 may be previously stored in a storage unit (not shown). For example, the first reference width used to determine the preceding vehicle Cp1 may be stored in advance in the storage unit. Also, an algorithm for obtaining the second reference width used to determine the preceding vehicle Cp2 may be previously stored in the storage unit. In addition, the reference curvature used to determine the curved driving lane W may be stored in advance in the storage unit, or the above-described reference time may be stored in advance.

9 is a flowchart for controlling the traveling speed of the host vehicle in the CACC system 300 according to an embodiment of the present invention.

Referring to FIG. 9 , the CACC system 300 may acquire vehicle information of surrounding vehicles using V2V communication ( S100 ). The vehicle information may include information such as location information, speed, and acceleration by GPS, and in addition to this, information on the road on which each surrounding vehicle is traveling may also be included.

In addition, the CACC system 300 may determine a preceding vehicle and a preceding vehicle traveling in front of the own vehicle 700 using a camera, a distance sensor, etc. attached to the own vehicle 700 ( S200 ). In addition, the first target vehicle and the second target vehicle may be determined ( S300 ) by comparing the surrounding vehicle information obtained through V2V communication and the preceding vehicle and the preceding vehicle determined using the sensors of the own vehicle. Here, the first target vehicle becomes a target vehicle followed by the own vehicle 700 and the second target vehicle becomes a target vehicle followed by the first target vehicle. After determining the first target vehicle and the second target vehicle in this way, the CACC system 300 determines the driving speed of the own vehicle using the driving information of the first target vehicle and the second target vehicle (S400), Accordingly, the driving of the host vehicle may be controlled ( S500 ). Here, the driving information may be all information related to the first target vehicle and the second target vehicle including a speed, an acceleration position, and the like.

The CACC system 300 according to the embodiment disclosed in the above-described manner can ensure safety in consideration of both the first target vehicle Cp1 and the second target vehicle Cp2.

10 is a flowchart of determining a preceding vehicle and a preceding vehicle by using a sensor of the own vehicle in the CACC system 300 according to an embodiment of the present invention.

The CACC system 300 may first determine the driving lane W by using the front image ( S210 ). Specifically, the CACC system 300 may acquire a front image including lane information using a camera through the information collection unit 310 and determine the driving lane W by extracting the lane through image processing. can

When the driving lane W is determined, the CACC system 300 may determine a preceding vehicle driving the driving lane W using the detection result of the distance sensor 311 ( S220 ). To this end, the CACC system 300 may determine an object having a width greater than or equal to a predetermined first reference width among objects on the driving lane W detected by the distance sensor 311 as the preceding vehicle Cp1.

Then, the CACC system 300 may determine the preceding vehicle Cp2 traveling in the driving lane W using the determined position of the preceding vehicle Cp1 ( S230 ). For this, the CACC system 300 may obtain the second reference width corresponding to the position of the preceding vehicle Cp1. After acquiring the second reference width, the CACC system 300 may determine an object having a width greater than or equal to the second reference width among objects on the driving lane W detected by the distance sensor 311 as the preceding vehicle Cp2.

The CACC system 300 compares the thus-determined preceding vehicle Cp1 and the preceding vehicle Cp2 with information on surrounding vehicles obtained through the communication unit 320 to determine the first target vehicle and the second target vehicle (S300) can do.

Hereinafter, a control method of the CACC system 300 will be described in detail by dividing a case in which the driving lane W is a straight line and a case in which it is curved.

11 is a flowchart of determining a preceding vehicle and a preceding vehicle by using a sensor of the own vehicle in the CACC system 300 for a straight driving lane according to an embodiment of the present invention.

Referring to FIG. 11 , the CACC system 300 may determine the driving lane W using the forward image ( S210 ). Specifically, the CACC system 300 uses a camera to determine the forward image including lane information. can be obtained, and the driving lane W can be determined by extracting the lane through image processing.

When the driving lane W is determined, the CACC system 300 may determine the preceding vehicle Cp1 driving the driving lane W using the detection result of the distance sensor 311 ( S220 ). To this end, the CACC system 300 may determine an object having a width greater than or equal to a predetermined first reference width among objects on the driving lane W detected by the distance sensor 311 as the preceding vehicle Cp1.

The CACC system 300 may use the determined position of the preceding vehicle Cp1 to determine the minimum reference width that can be determined as the preceding vehicle Cp2, that is, the second reference width (S231). As described in FIG. 7 , the CACC system 300 may determine the positions of P1 , P2 , and P3 based on the position of the distance sensor 311 as an origin, and may determine the second reference width according to Equation 1 .

When the second reference width is confirmed, the CACC system 300 may identify an object having a width greater than or equal to the reference width among objects detected by the distance sensor 311 ( S232 ). Also, the CACC system 300 may check whether the object identified for the reference time has a width greater than or equal to the second reference width ( S233 ).

If the identified object does not have a width greater than or equal to the second reference width during the reference time, the CACC system 300 does not determine the identified object as the preceding vehicle and ends.

On the other hand, if the object identified during the reference time has a width greater than or equal to the second reference width, the CACC system 300 may determine the identified object as the preceding vehicle Cp2 ( S234 ).

12 is a flowchart of determining a preceding vehicle and a preceding vehicle by using a sensor of the own vehicle in the CACC system 300 for a curved driving lane according to an embodiment of the present invention.

Referring to FIG. 12 , the CACC system 300 may determine a driving lane W using the forward image ( S210 ). Specifically, the CACC system 300 uses a camera to determine a forward image including lane information. can be obtained, and the driving lane W can be determined by extracting the lane through image processing.

When the driving lane W is determined, the CACC system 300 may determine the preceding vehicle Cp1 driving the driving lane W using the detection result of the distance sensor 311 ( S220 ). To this end, the CACC system 300 may determine an object having a width greater than or equal to a predetermined first reference width among objects on the driving lane W detected by the distance sensor 311 as the preceding vehicle Cp1.

The CACC system 300 may use the determined position of the preceding vehicle Cp1 to determine the minimum reference width that can be determined as the preceding vehicle Cp2, that is, the second reference width (S231). As described in FIG. 7 , the CACC system 300 may determine the positions of P1 , P2 , and P3 based on the position of the distance sensor 311 as an origin, and may determine the second reference width according to Equation 1 .

When the second reference width is confirmed, the CACC system 300 may identify an object having a width greater than or equal to the reference width among objects detected by the distance sensor 311 ( S232 ). In addition, the CACC system 300 may check whether a plurality of surfaces of the identified object are detected by the distance sensor 311 ( S235 ).

If the plurality of faces of the identified object are not detected, the CACC system 300 does not determine the identified object as the preceding vehicle and ends.

On the other hand, if a plurality of surfaces of the identified object are not detected, the CACC system 300 may determine the identified object as the preceding vehicle Cp2 ( S234 ).

As described above, the CACC system proposed in the present invention can provide a safe driving environment to the driver by controlling the speed by considering not only the first target vehicle but also the second target vehicle that is the target vehicle of the first target vehicle.

Meanwhile, in the present specification, it should be understood that CACC is exemplified for convenience of description. It should be understood that CACC is only one of several ADAS functions, and the CACC implementation presented by the present invention may be used to implement other related ADAS functions. For example, the method presented in the present invention is CACC, Adaptive Cruise Control (ACC), Lane Change Decision Aid System (LCAS), Lane Departure Warning System (LDWS), Lane Keeping Assistance System (LKAS), Road Boundary Departure (RBDPS). Prevention System), Pedestrian Detection and Collision Mitigation System (PDCMS), Curve Speed Warning System (CSWS), Forward Vehicle Collision Warning System (FVCWS), Low Speed Following (LSF), etc. It can also be used to implement a combination of

In one or more exemplary embodiments, the functions described may be implemented in hardware, software, firmware, or any combination thereof. If implemented in software, the functions may be stored on or transmitted over as one or more instructions or code on a computer-readable medium. Computer-readable media includes both computer storage media and communication media including any medium that facilitates transfer of a computer program from one place to another. A storage medium may be any available medium that can be accessed by a computer. By way of example, and not limitation, such computer readable media may carry or store desired program code in the form of RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage device, or instructions or data structures. and may include any other medium accessible by a computer. Also, any connection is properly termed a computer-readable medium. For example, if the Software is transmitted from a website, server, or other remote source using coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL), or wireless technologies such as infrared, radio and microwave, coaxial cable; Fiber optic cables, twisted pair, DSL, or wireless technologies such as infrared, radio and microwave are included in the definition of a medium. Discs and discs as used herein include compact discs (CDs), laser discs, optical discs, digital versatile discs (DVDs), floppy discs and Blu-ray discs, which disks usually contain data magnetically. On the other hand, discs optically reproduce data by means of a laser. Combinations of the above should also be included within the scope of computer-readable media.

When embodiments are implemented as program code or code segments, a code segment is a procedure, function, subprogram, program, routine, subroutine, module, software package, class, or instructions, data structures, or program statement. It should be appreciated that any combination of these may be represented. Code segments may be coupled to other code segments or hardware circuits by passing and/or receiving information, data, arguments, parameters, or memory contents. Information, arguments, parameters, data, and the like may be communicated, forwarded, or transmitted using any suitable means, including memory sharing, message passing, token passing, network transmission, and the like. Additionally, in certain aspects the steps and/or operations of a method or algorithm may be one or more of the codes and/or instructions on a machine-readable medium and/or computer-readable medium, which may be incorporated into a computer program product. may reside as any combination or set of

In an implementation in software, the techniques described herein may be implemented in modules (eg, procedures, functions, etc.) that perform the functions described herein. The software codes may be stored in memory units and executed by processors. The memory unit may be implemented within the processor or external to the processor, in which case the memory unit may be communicatively coupled to the processor by various means as is well known.

In a hardware implementation, the processing units may include one or more application specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs), field programmable gate arrays (FPGAs), processors, It may be implemented within a controller, microcontroller, microprocessor, other electronic units designed to perform the functions described herein, or a combination thereof.

What has been described above includes examples of one or more embodiments. Of course, it is not possible to describe every possible combination of components or methods for purposes of describing the above-described embodiments, and those skilled in the art will recognize that many further combinations and permutations of various embodiments are possible. Accordingly, the described embodiments are intended to embrace all alternatives, modifications and adaptations falling within the spirit and scope of the appended claims. Moreover, to the extent that the term "comprises" is used in the description or claims, such term is similar to "consisting of" as interpreted when the term "consisting of" is used as a transitional word in the claims. will be included in this way.

As used herein, the term "infer" or "inference" generally refers to the process of making judgments or inferences about the state of a system, environment, and/or user from a set of observations captured by events and/or data. say Inference may be used to identify a particular situation or action, or may generate a probability distribution over states, for example. An inference may be probabilistic, ie, the calculation of a probability distribution for the states in question based on a consideration of data and events. Inference may also refer to techniques used to construct higher-level events from a set of events and/or data. This inference is based on a set of observed events and/or new events or actions from stored event data, whether the events are closely correlated in time, and whether the events and data come from one or several event and data sources. to estimate

Moreover, as used herein, terms such as "component," "module," "system," and the like, relate to a computer, such as, but not limited to, hardware, firmware, a combination of hardware and software, software or software in execution. It contains entities. For example, a component may be, but is not limited to being, a process running on a processor, a processor, an object, an executable thread of execution, a program, and/or a computer. By way of example, both an application running on a computing device and a computing device may be a component. One or more components may reside within a process and/or thread of execution, and a component may be centralized on one computer and/or distributed between two or more computers. In addition, these components may execute from various computer-readable media having various data structures stored thereon. Components may follow a signal having one or more data packets (eg, data from a local system, another component of a distributed system, and/or data from any component that interacts with other systems by signal across a network, such as the Internet). etc. may be communicated by local and/or remote processes.

10: Rode Side Equipment (RSE)
300: CACC system
310: information collection unit
320: communication unit
330: control unit
331: state management unit
333: driving management unit
335: target vehicle selection unit

Claims (14)

A cooperative adaptive cruise control (CACC) system provided in the own vehicle and controlling the traveling speed of the own vehicle, the system comprising:
a communication unit for obtaining vehicle information of surrounding vehicles using V2V (Vehicle to Vehicle) communication;
an information collection unit configured to obtain vehicle information of a surrounding vehicle and vehicle information of the own vehicle using sensors provided in the own vehicle;
a controller for selecting a target vehicle to be followed by the own vehicle based on vehicle information of the surrounding vehicles and vehicle information of the own vehicle, and controlling a traveling speed of the own vehicle based on the selected speed information of the target vehicle; including,
The control unit is
selecting a first potential interest vehicle group including vehicles existing in the same lane as the own vehicle;
Among the vehicles in the first potential interest vehicle group, using the V2V communication and the sensors, selecting vehicles existing within a certain distance from the own vehicle as a second potential interest vehicle group;
A vehicle in which the difference between the vehicle speed obtained through the V2V communication and the vehicle speed obtained through the sensors among the vehicles in the second potential vehicle group is less than a preset value is selected as the third potential vehicle group of interest and,
selecting at least one vehicle in the third potential vehicle group as the target vehicle;
Coordinated adaptive cruise control system. According to claim 1,
Further comprising a driving unit for controlling the throttle (throttle) and the brake,
The control unit controls the driving unit to control the traveling speed of the host vehicle,
Coordinated adaptive cruise control system. According to claim 1,
Further comprising a DVI unit that can inform the driver of the state information of the cooperative adaptive cruise control system,
Coordinated adaptive cruise control system. According to claim 1, wherein the control unit,
a state management unit for managing the state of the cooperative adaptive cruise control system;
a target vehicle selector configured to select the target vehicle based on vehicle information of the surrounding vehicles and vehicle information of the own vehicle; and
a driving management unit controlling the driving speed of the host vehicle based on the speed information of the target vehicle; containing,
Coordinated adaptive cruise control system. 5. The method of claim 4,
The state management unit is in an OFF state in which the cooperative adaptive cruise control system does not operate, in a standby state that operates but does not control the traveling speed of the own vehicle, and there is no vehicle in the region of interest connected by V2V communication. There is an ACC active state that controls the traveling speed of the own vehicle using only the information obtained from the ACC, and there are surrounding vehicles in the region of interest connected by V2V communication. Displaying the state of the cooperative adaptive cruise control system as one of the cooperative activation states for controlling the traveling speed of the host vehicle using information obtained from the vehicle,
Coordinated adaptive cruise control system. 5. The method of claim 4,
The information collection unit includes a distance sensor for detecting an object in front,
The target vehicle selection unit determines the existence of a vehicle traveling in the same lane as the driving lane of the host vehicle based on the detection result of the distance sensor,
Coordinated adaptive cruise control system. 7. The method of claim 6,
The target vehicle selection unit determines, as a preceding vehicle of the host vehicle, an object on the driving lane of the host vehicle having a width greater than or equal to a predetermined first reference width according to a detection result of the distance sensor;
Coordinated adaptive cruise control system. 7. The method of claim 6,
The distance sensor comprises a lidar (Lidar),
Coordinated adaptive cruise control system. 7. The method of claim 6,
The information collection unit further comprises a camera for acquiring a front image,
The target vehicle selection unit obtains information on the lane in which the host vehicle is driving from the front image acquired by the camera,
Coordinated adaptive cruise control system. A speed control method of a cooperative adaptive cruise control (CACC) system provided in the own vehicle and controlling the traveling speed of the own vehicle, the method comprising:
obtaining vehicle information of surrounding vehicles using V2V communication;
obtaining vehicle information of a neighboring vehicle and vehicle information of the own vehicle using a sensor of the own vehicle;
selecting a target vehicle to be followed by the own vehicle based on the vehicle information of the surrounding vehicle and the vehicle information of the own vehicle;
determining a driving speed of the host vehicle by using the driving information of the target vehicle; and
Including; controlling the host vehicle according to the determined driving speed;
The step of determining the target vehicle includes:
selecting a first potential interest vehicle group including vehicles existing in the same lane as the own vehicle;
selecting vehicles existing within a predetermined distance from among the vehicles in the first potential interest vehicle group as a second potential interest vehicle group using the V2V communication and a sensor of the own vehicle;
Among the vehicles in the second potential interest vehicle group, a vehicle in which a difference between the vehicle speed obtained through the V2V communication and the vehicle speed obtained through the sensor is less than a preset value is selected as the third potential interest vehicle group to do; and
selecting at least one vehicle in the third potential vehicle group as the target vehicle;
The speed control method of the CACC system. 11. The method of claim 10,
detecting an object in front; and
Further comprising the step of determining a preceding vehicle traveling in the same lane as the driving lane of the host vehicle based on the detection result,
The speed control method of the CACC system. 12. The method of claim 11,
The step of determining the preceding vehicle includes:
determining, as the preceding vehicle, an object on the driving lane of the host vehicle having a width equal to or greater than a predetermined first reference width according to a detection result of the step of detecting the front object;
The speed control method of the CACC system. 12. The method of claim 11,
The step of detecting the distance to the front object comprises:
Using a lidar (Lidar) comprising the step of sensing the distance to the front object,
The speed control method of the CACC system. 12. The method of claim 11,
acquiring a front image; and
Determining a driving lane of the own vehicle from the front image; further comprising,
The speed control method of the CACC system.

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