KR102606258B1 - Cooperative driving control apparatus and method - Google Patents

Abstract

The present invention relates to a cooperative driving control technology, wherein, at the time of canceling cooperative driving, the forward separation distance between the other vehicles in front and the best vehicle present in the cooperative driving group, and the distance present in the rear of the last vehicle in the cooperative driving group By applying different cooperative driving cancellation methods for various modes depending on the size of the rear separation distance between the other vehicles behind and the last vehicle, the cooperative driving state can be safely canceled while excluding the possibility of collision with the front and rear vehicles.

Description

COOPERATIVE DRIVING CONTROL APPARATUS AND METHOD}

The present invention relates to cooperative driving control technology, and more specifically, to technology for disengaging or leaving cooperative driving while multiple vehicles are cooperatively driving.

As information and communication technology (ICT) is incorporated into vehicles, the next-generation intelligent transportation system (C-ITS, Cooperative Intelligent Transportation System) is being researched.

Advanced transportation countries are already introducing various intelligent transportation system pilot projects and services. These services are divided into services that provide traffic safety information closely related to traffic accidents and services that provide driver convenience information.

Meanwhile, conventionally, the focus has been on developing services limited to communication between vehicles and infrastructure by utilizing WAVE (Wireless Access in Vehicular Environment) technology developed for high-speed mobile vehicles. In other words, communication services are provided by broadcasting information necessary for traffic from a base station (RSU, Road Side Unit) installed on the roadside to a vehicle (OBU, On Board Unit), or by exchanging data necessary for services such as the Internet between vehicles. exist

However, in order to maximize the recent increase in traffic volume and highway use efficiency, vehicle platoon driving or vehicle cooperative driving technology, in which multiple vehicles drive in groups while maintaining close distance, has been developed. Research and development are underway.

This vehicle platoon or vehicle cooperative driving technology is a technology in which a group of multiple vehicles, including a leader vehicle, drives while keeping successive vehicles close by controlling the distance between vehicles.

At this time, vehicle spacing is maintained by exchanging information on the movement of vehicles in the group and potential abnormal situations through inter-vehicle communication and controlling accordingly.

Meanwhile, while performing such cooperative driving, when a certain condition or point occurs, the cooperative driving relationship must be canceled. At this time, cooperative driving must be canceled safely depending on whether there are other vehicles close to the front or rear in the same lane of the cooperative driving group.

However, currently only discussions are being conducted on inter-vehicle communication and vehicle control during the period of cooperative driving or autonomous cluster driving, and the development of technology to cancel cooperative driving is insufficient.

Against this background, the purpose of an embodiment of the present invention is to provide a technology that allows vehicles to safely separate from a cooperative driving group when vehicle cooperative driving or vehicle platoon driving is canceled.

Another object of the present invention is that, in the process of disengaging from a cooperative driving relationship in which multiple vehicles, including a leader vehicle, drive while maintaining a certain distance, several vehicles are connected according to the position of the front or rear vehicle existing in the same lane of the cooperative driving vehicle group. The aim is to provide a technology that enables safe cooperative driving release by performing a cooperative driving departure mode operation.

Another object of the present invention is to reduce the possibility of vehicle collision when cooperative driving is canceled by selectively performing three cooperative driving release modes according to the distance of other vehicles present in front and behind the cooperative driving vehicle group when cooperative driving is canceled. It is ordered.

In order to achieve the above-described object, in one embodiment of the present invention, a cooperative vehicle is disposed inside the leader vehicle to control cooperative driving in which vehicles in a cooperative driving group including a leader vehicle and one or more follower vehicles drive cooperatively. A driving control device, comprising: a forward separation distance between the first vehicle and a front other vehicle present in front of the last vehicle in the cooperative driving group at the time of release of cooperative driving; and a rear other vehicle present behind the last vehicle in the cooperative driving group; a front and rear distance determination unit that detects the rear separation distance between the last vehicles; a cooperative driving cancellation request generating unit that generates different cooperative driving cancellation requests depending on whether the front separation distance and the rear separation distance exceed a front threshold and a rear threshold, respectively; A cooperative driving control device including a cooperative driving cancellation request transmission unit that transmits the cooperative driving cancellation request uniquely generated for each follow vehicle to the following vehicle.

In another embodiment of the present invention, there is a device for controlling cooperative driving in which vehicles in a cooperative driving group including a leader vehicle and one or more follower vehicles drive cooperatively, which is present in the leader vehicle and is activated at the time of release of cooperative driving. Detecting a front separation distance between the first vehicle and a front other vehicle that exists in front of the last vehicle in the driving group, and a rear separation distance between the last vehicle and a rear other vehicle that exists behind the last vehicle in the cooperative driving group, a cooperative driving master control device that generates different cooperative driving release requests and transmits them to the following vehicle depending on whether the front separation distance and the rear separation distance exceed a front threshold and a rear threshold, respectively; Included in the follower vehicle, a cooperative driving slave control device that receives a request to cancel cooperative driving from the cooperative driving control device of the leader vehicle and then changes the vehicle driving state to cancel cooperative driving accordingly. Provides a control device.

In another embodiment of the present invention, as a method of controlling release from cooperative driving in which vehicles in a cooperative driving group including a leader vehicle and one or more follower vehicles drive cooperatively, the cooperative driving master device included in the leader vehicle is used. It is performed using a first step of deciding to start canceling cooperative driving; Detects the forward separation distance between the first vehicle and the other vehicle in front of the last vehicle in the cooperative driving group, and the rear separation distance between the last vehicle and the other vehicle in the rear that exists behind the last vehicle in the cooperative driving group. The second step of doing; A third step of generating different cooperative driving release requests depending on whether the front separation distance and the rear separation distance exceed a front threshold and a rear threshold, respectively; A fourth step of transmitting the cooperative driving cancellation request uniquely generated for each following vehicle to the following vehicle.

According to an embodiment of the present invention as described below, in the process of releasing from a cooperative driving relationship in which multiple vehicles including a leader vehicle drive while maintaining a certain interval, the front or rear vehicle present in the same lane of the cooperative driving vehicle group By performing several cooperative driving departure mode operations depending on the position of the rear vehicle, it is possible to safely disengage cooperative driving.

More specifically, the possibility of vehicle collision when cooperative driving is canceled can be reduced by selectively performing three cooperative driving release modes depending on the distance to other vehicles in front and behind the cooperative driving vehicle group when cooperative driving is canceled. .

Figure 1 schematically shows a cooperative driving state to which the present invention can be applied.
Figure 2 shows the overall configuration of the cooperative driving system according to the present invention.
Figure 3 is a functional block diagram of the cooperative driving master control device included in the leader vehicle according to the present invention.
Figure 4 shows a situation in the first mode for canceling cooperative driving and a method for canceling cooperative driving in the first mode.
Figure 5 shows a situation in a second mode for canceling cooperative driving and a method for canceling cooperative driving in the second mode.
Figure 6 shows a situation in the third mode for canceling cooperative driving and a method for canceling cooperative driving in the third mode.
Figure 7 is an overall flowchart of the cooperative driving release method according to the present invention.
Figure 8 is a flowchart illustrating in detail the cooperative driving release process for each mode according to an embodiment of the present invention.

Hereinafter, some embodiments of the present invention will be described in detail with reference to the exemplary drawings. In adding reference numerals to components in each drawing, identical components may have the same reference numerals as much as possible even if they are shown in different drawings. Additionally, when describing the present invention, if it is determined that a detailed description of a related known configuration or function may obscure the gist of the present invention, the detailed description may be omitted.

Additionally, when describing the components of the present invention, terms such as first, second, A, B, (a), and (b) may be used. These terms are only used to distinguish the component from other components, and the nature, sequence, order, or number of the components are not limited by the term. When a component is described as being “connected,” “coupled,” or “connected” to another component, that component may be directly connected or connected to that other component, but there are no other components between each component. It should be understood that may be “interposed” or that each component may be “connected,” “combined,” or “connected” through other components.

Figure 1 schematically shows a cooperative driving state to which the present invention can be applied.

Cooperative driving in FIG. 1 shows a case where a total of n vehicles, including the leader vehicle, perform cooperative driving.

In this specification, a total of n cooperative driving vehicles are expressed as a cooperative driving group, and among the vehicles in the cooperative driving group, one or more vehicles that control cooperative driving of the entire group are referred to as leader vehicles (Leader Vehicle; 110), and the remaining vehicles are follower vehicles. Expressed as (120, 130).

Cooperative driving is a driving method in which vehicles in a total of n cooperative driving groups, including the leader vehicle 110, drive in the same lane while maintaining a constant distance, which can not only reduce fuel efficiency but also reduce traffic congestion. .

The leader vehicle 110 may be located at the forefront among the vehicles in the entire cooperative driving group, but is not limited thereto and may drive in the middle of the entire group of vehicles or in other positions.

This leader vehicle 110 detects and determines the surrounding conditions necessary for cooperative driving, generates control data for each vehicle included in the cooperative driving group, and transmits it to the follower vehicles 120 and 130 included in the group. .

The follower vehicles 120 and 130 autonomously operate the engine, steering, and braking devices using control data transmitted from the leader vehicle, thereby driving while maintaining a certain separation distance from the vehicle in front of them.

At this time, the constant interval between vehicles included in the cooperative driving group is expressed as a distance such as the headway distance (Sr) or headway time, which is a concept of TTC (Time-To-Collision); HW) can be expressed as the same time.

In this specification, the inter-vehicle distance during cooperative driving is indicated as Sr, and the inter-vehicle headway time is indicated as HW0.

In such cooperative driving, a predetermined group of vehicles may perform cooperative driving from the start of driving, but may also be incorporated into a cooperative driving group during the driving process.

Meanwhile, in such cooperative driving, at a certain point, a situation arises in which the cooperative driving relationship must be canceled or some or all of the vehicles in the group must deviate from the cooperative driving group according to a command from the leader vehicle.

In this specification, the case where all vehicles in cooperative driving must end their cooperative driving relationship is referred to as cooperative driving cancellation. However, it is not limited to these expressions, and various other expressions such as departure from cooperative driving and end of cooperative driving may be used.

When canceling cooperative driving, multiple vehicles must deviate from the cooperative driving path at the same time, so if other vehicles are close to the front or rear of the cooperative driving group, or in the lane next to it, there is a risk of collision with other vehicles during the canceling of cooperative driving. .

Therefore, the present invention detects the distance to other vehicles in front or behind the cooperative driving group when canceling cooperative driving, and performs various modes of cooperative driving canceling methods accordingly, thereby promoting stability in the process of canceling cooperative driving. I want to do it.

Figure 2 shows the overall configuration of the cooperative driving system according to the present invention.

The cooperative driving system according to the present invention includes one or more leader vehicles and one or more follower vehicles that perform cooperative driving after receiving a control command from the leader vehicle, and cooperatively drives all cooperative driving vehicles including the leader vehicle and follower vehicle. Expressed as a group.

The present invention is applied when it is time to cancel cooperative driving during cooperative driving, and the cooperative driving state is canceled by leaving cooperative driving in response to a request for canceling cooperative driving.

At this time, after deciding to cancel cooperative driving, the leader vehicle 110 generates a cooperative driving release request message containing a unique command for each follower vehicle and transmits it to each follower vehicle. To this end, inside the leader vehicle A cooperative driving master control device 200 is included.

Meanwhile, inside the follower vehicles 120 and 130, a request to cancel cooperative driving is received from the cooperative driving master control device of the leader vehicle, and the driving system (braking, steering, etc.) of the own vehicle is controlled based on the command contained therein to enable cooperative driving. It may be configured to include a cooperative driving slave device that controls it to escape from the state.

That is, the entire cooperative driving system as shown in FIG. 2 is a device that controls cooperative driving in which vehicles in a cooperative driving group including a leader vehicle 110 and two or more follower vehicles 120 and 130 drive cooperatively. , the front separation distance (Df) between the leading vehicle and the other vehicle in front, which exists in the leader vehicle 110 and is in front of the best vehicle in the cooperative driving group at the time of release of cooperative driving, and behind the last vehicle in the cooperative driving group, Detects the rear separation distance (Dr) between the remaining rear vehicle and the last vehicle, and makes different cooperative driving cancellation requests for each mode depending on whether the front separation distance and rear separation distance exceed the front threshold and rear threshold, respectively. Includes a cooperative driving master control device 200 that generates and transmits to the follow vehicle,

In addition, inside the follower vehicles 120 and 130, there is a cooperative driving slave that receives a request to cancel cooperative driving from the cooperative driving master control device 200 of the leader vehicle and then changes the vehicle driving state to cancel cooperative driving accordingly. A control device 300 is included.

The cooperative driving master control device 200 and the cooperative driving slave control device 300 may be composed of separate hardware and software and installed inside the leader vehicle and follower vehicle, but may be installed as a single module inside the existing vehicle control system. It might be included.

Meanwhile, in an embodiment of the present invention, a total of three or more cooperative driving release modes can be operated depending on the comparison result between the front separation distance, the rear separation distance, and the front/rear threshold, and as an example below, the front separation Mode 1, where both the distance (Df) and the rear separation distance (Dr) are greater than the front and rear thresholds, and the front separation distance (Df) is below the front threshold, but the rear separation distance (Dr) is below the rear threshold. The second mode, which is a larger case, illustrates a method including mode 3, where both the front separation distance (Df) and the rear separation distance (Dr) are smaller than the threshold.

The detailed configuration of the cooperative driving master control device 200 of the leader vehicle 110 and the cooperative driving release process according to modes 1 to 3 will be described in more detail below with reference to FIGS. 3 to 8.

Figure 3 is a functional block diagram of the cooperative driving master control device included in the leader vehicle according to the present invention.

The cooperative driving control device 300 as shown in FIG. 3 is disposed inside the leader vehicle 110 and requests a cooperative driving release including a certain command so that the cooperative driving release process can be performed in a different way for each mode ( performs the function of creating a message and sending it to each follower vehicle.

More specifically, as shown in FIG. 3, the cooperative driving control device 300 includes a front and rear distance determination unit 310 that determines the distance between the front and rear other vehicles and the cooperative driving group at the time of canceling cooperative driving, and a distance determination unit of the distance determination unit. A cooperative driving release request generator 320 selects a cooperative driving release mode according to the determination result and generates a cooperative driving release request appropriate for the mode, and a cooperative driving release request generation unit 320 transmits the generated cooperative driving release request to each follow vehicle. It may be configured to include a request transmission unit 330.

Additionally, the cooperative driving control device 300 included in the leader vehicle may additionally include a wireless communication unit 340 that receives data such as identification information and driving information of the follower vehicle from the follower vehicle.

To transmit and receive data between the leader vehicle and the follower vehicle, one of several currently developed V2X (Vehicle-to-everything) communications methods can be used.

As an example of such V2X communication, the IEEE 802.11p wireless communication standard technology is used in the physical layer, the CSMA/CA (Carrier Sense Multiple Access/Collision Avoid) protocol is used in the MAC layer, and the platoon-multicast method is used in the network layer. This applicable communication method is possible, but is not limited to this, and any wireless communication technology may be used as long as information can be transmitted and received between the leader vehicle and the follower vehicle.

The front and rear distance determination unit 310 determines the front separation distance (Df) between the front vehicle and the front vehicle that exists in front of the best vehicle in the cooperative driving group at the time of canceling cooperative driving, and the rear vehicle that exists behind the last vehicle in the cooperative driving group. It performs the function of determining the rear separation distance (Dr) between the other vehicle and the last vehicle.

Typically, during cooperative driving, the leader vehicle is the one that is most advanced, and in this case, the vehicle front separation distance (Df) can be determined through sensor modules such as front radar and front camera mounted on the leader vehicle.

However, the leader vehicle does not necessarily have to be placed at the very front of the group, and may be in the middle of the group or any other position.

As such, if the leader vehicle is not at the front or rear of the group, the aforementioned front separation distance (Df) and rear separation distance (Dr) cannot be directly calculated by the leader vehicle.

In this case, the cooperative driving control device 300 of the leader vehicle detects the follower vehicle at the head of the group (i.e., the best vehicle) and the follower vehicle at the rear of the group (i.e., the last vehicle) through the wireless communication unit 340. By receiving information about the front separation distance (Df) and the rear separation distance (Dr), the front separation distance (Df) and the rear separation distance (Dr) at the start of cooperative driving release can be determined.

Of course, the following vehicle at the rear of the group (i.e., the last vehicle) can calculate the rear separation distance (Dr), which is the distance from other vehicles behind it, using a rear camera or side/rear radar, etc. Information about the rear separation distance (Dr) can be transmitted to the leader vehicle.

The first and last vehicles use various sensors (cameras, radars, ultrasound, etc.) mounted on them to calculate the distance to other vehicles in front or behind, thereby calculating the front separation distance (Df) and rear separation distance (Dr). Since the method of calculating can use a distance calculation algorithm for each sensor, detailed description thereof is omitted in this specification.

The cooperative driving cancellation request generating unit 320 performs a function of generating different cooperative driving cancellation requests depending on whether the front separation distance and the rear separation distance exceed the front threshold and the rear threshold, respectively.

More specifically, in the case of the first mode in which the front separation distance (Df) and the rear separation distance (Dr) exceed the front threshold and the rear threshold, respectively, the cooperative driving release request generator 320 sets the cooperative driving group Among the vehicles included within the vehicle, a cooperative driving release request including an acceleration command is generated for a follower vehicle that is ahead of the reference vehicle in the central area, and a headway distance increase command or headway distance increase command is generated for the follower vehicle that is rearward of the reference vehicle. Generate a cooperative driving release request including a way time increase command.

In this first mode, the reference vehicle may be a vehicle located in the center among all vehicles included in the group, and this reference vehicle does not necessarily need to be the leader vehicle.

In other words, if there are no other vehicles close to the front or rear of the group at the start of cooperative driving cancellation, the vehicle located in front accelerates based on the reference vehicle in the middle of the group, and the vehicle located in the rear accelerates, and the vehicle located in the rear accelerates, and the vehicle located in the rear accelerates due to the inter-vehicle distance (headway time or headway time). By increasing the way distance, the overall distance between cooperative driving vehicles is widened to proceed with a safe cooperative driving release process.

In mode 1, the acceleration command included in the cooperative driving release message transmitted to the vehicle located in front of the reference vehicle may indicate an acceleration value determined according to Equation 1 below.

Specifically, the acceleration command may cause the i-th front follower vehicle located in front of the reference vehicle to have an acceleration according to Equation 1 below.

[Equation 1]

a _i =a _i-1 +2△s/t ₀

In Equation 1, ai is the acceleration indication value of the ith front vehicle, △s is the safe relative distance, and t ₀ is the cooperative driving release period.

Meanwhile, a ₀ is the acceleration of the reference vehicle and is set to 0. In other words, during the process of canceling cooperative driving, the reference vehicle drives at a constant speed.

△s is a safety relative distance (Additional Relative Distance to be secured), which is determined as the difference between the target inter-vehicle distance Sr' when cooperative driving is canceled and Sr, the inter-vehicle distance during cooperative driving.

This Δs is a predetermined value to perform safe cooperative driving cancellation, and may be a constant constant, but may be set variably depending on the driving environment at the time of cooperative driving cancellation.

For example, in slippery road conditions or when the speed of the lead vehicle (V _L ) during cooperative driving is high, △s can be set large.

In addition, △s may be determined in conjunction with the front and rear thresholds described above. For example, when the front and rear thresholds are set to a large value, since there are no obstacles up to a long distance in the front and rear, △s is also large. The value can be set.

In other words, △s, the safe relative distance when disabling cooperative driving, can be set variably according to road surface conditions, braking distance, cooperative driving speed, etc., and is proportional to the front threshold and rear threshold for determining cooperative driving disengaging mode. can be set.

The cooperative driving cancellation period, t ₀ , refers to the period from the start of cooperative driving cancellation until the cooperative driving cancellation is completed. The cooperative driving cancellation period, t ₀ , may be set in advance depending on the road environment, etc.

For example, if cooperative driving is performed on a highway where the road driving environment changes rapidly, t ₀ , the cooperative driving release period, should be set relatively short.

As shown in Equation 1, in the first mode in which the front separation distance (Df) and the rear separation distance (Dr) exceed the front threshold and the rear threshold, respectively, the vehicle in front of the reference vehicle accelerates with a greater acceleration. The distance between vehicles can be quickly increased.

In other words, the front vehicle with i=1, which is directly in front of the reference vehicle, accelerates with an acceleration of a ₁ =2△s/t ₀ , and the vehicle with i=2, which is one further ahead, accelerates with a ₂ = a ₁ +2△. It accelerates with an acceleration of s/t ₀ = 4△s/t ₀ .

Accordingly, when cooperative driving is initiated, the vehicle in front of the center vehicle accelerates more significantly, so that the distance between vehicles in front of the reference vehicle can be uniformly increased.

Meanwhile, in mode 1, the reference vehicle (a = 0) is assumed to be driving at a constant speed, so the vehicle behind the reference vehicle must be slowed down during the process of canceling cooperative driving, and for this purpose, the rear vehicle must use Equation 2 below: The headway increase command is included in the cooperative driving cancellation request and transmitted to the vehicle.

[Equation 2]

HWr = (Sr+△s)/V _L

where HWr is the headway time for the vehicle behind, △s is the safety relative distance, V _L is the best vehicle speed at the start of cooperative driving cancellation.

V _L may be the vehicle speed of the best vehicle at the start of cooperative driving release, but is not limited thereto, and in some cases may be the vehicle speed of the leader vehicle, or the vehicle speed of the entire group if the entire group was driving at a constant speed.

In other words, during cooperative driving, the headway time is set to HW0 to maintain the inter-vehicle distance at Sr, but during the cooperative driving release period, the target inter-vehicle distance must increase to Sr', so the headway time HWr for the rear vehicle is calculated as above. It increases as shown in Equation 2.

Meanwhile, in the case of the second mode, where the front separation distance (Df) is less than the front threshold but the rear separation distance (Dr) is greater than the rear threshold, the cooperative driving release request generator 320 is included in the cooperative driving group. Among the vehicles, a cooperative driving cancellation request including a headway distance increase command or a headway time increase command is generated for all rear following vehicles except the best vehicle.

At this time, in the second mode, the command to increase the headway time for all rear following vehicles except the best vehicle among the vehicles included in the group can be determined as in Equation 2 described above.

That is, in the second mode, where the front separation distance (Df) is less than the front threshold but the rear separation distance (Dr) is greater than the rear threshold, all rear vehicles placed behind the best vehicle maintain a constant headway time. By increasing the distance between vehicles to Sr', it is released from cooperative driving.

Meanwhile, in the second mode, it is desirable to increase the inter-vehicle distance first as the vehicle is placed furthest back.

That is, it is preferable that the distance between vehicles in the second mode is increased sequentially starting from the rear vehicle, and for this purpose, the cooperative driving cancellation request generator 320 first sends a cooperative driving cancellation request message including a headway time increase command to the last vehicle. It is desirable to transmit a cooperative driving cancellation request message to the vehicle ahead after a certain time interval.

The cooperative driving release request message may not only include the above-described acceleration command or headway time increase command, but may also include the identifier of the following vehicle to which the command will be applied.

In addition, in order to sequentially increase the inter-vehicle distance in the second mode, in addition to the headway time increase command and the follow vehicle identifier, release operation start time information to initiate the headway time increase command may also be included, and release operation start point information may be included. By setting it differently, control is possible to sequentially increase the distance between vehicles from the rear vehicle.

Of course, if the cancellation operation start time information is not used, the cooperative driving cancellation request generating unit 320 may sequentially generate cooperative driving cancellation requests starting from the rearmost follow vehicle and transmit them to the corresponding follow vehicle.

Below, the third mode is explained.

In the case of the third mode where the front separation distance (Df) and the rear separation distance (Dr) are less than the front threshold and the rear threshold, respectively, the cooperative driving release request generator 320 detects other vehicles in the adjacent lane of the cooperative driving lane. After detection, if there are no other vehicles in the adjacent lane, a cooperative driving release request including a lane change command is generated and transmitted to one or more follower vehicles among the vehicles included in the cooperative driving group.

At this time, the leader vehicle itself may detect another vehicle in an adjacent lane using a side radar, etc., or the detection result of another follower vehicle may be transmitted to determine whether the other vehicle is present.

In this third mode, the leader vehicle can confirm that there are other vehicles in the adjacent lane only at certain locations within the group driving range of the entire group currently driving, and only for follower vehicles that are unlikely to collide with other adjacent vehicles even if the lane changes. A cooperative driving cancellation or departure command can be granted by changing lanes.

Even in this case, the cooperative driving release request message may include, in addition to the above-described lane change command, the identifier of the following vehicle to which the command will be applied, and the following vehicle may use the lane change command included in the cooperative driving release request sent to it. You can deviate from cooperative driving by changing lanes.

In addition, in the third mode, the leader vehicle can identify the presence of other nearby vehicles only on one of the left and right adjacent lanes, so lane change direction information indicating the direction in which lane change is possible between left and right for a follower vehicle that can deviate by changing lanes (lane change direction information ( Left or right) could also be included in the lane change command and transmitted.

In this way, according to the present invention, at the time of canceling cooperative driving, the front separation distance (Df) between the front vehicle and the best vehicle in the cooperative driving group, and the rear vehicle in the cooperative driving group behind the last vehicle. By applying different cooperative driving release methods for various modes depending on the size of the rear separation distance (Dr) between the vehicle and the last vehicle, the cooperative driving state can be safely released while excluding the possibility of collision with the front and rear vehicles.

Figures 4 to 6 show the first mode, second mode, and third mode for canceling cooperative driving, and a method for canceling cooperative driving in each mode.

In the description of FIGS. 4 to 6, it is assumed that there are a total of 5 vehicles included in the cooperative driving group, the reference vehicle is placed in the center, and the leader vehicle is placed at the front.

Of course, the present invention is not limited to this assumption, and is not limited to the case where the reference vehicle is limited to the middle vehicle or the leader vehicle is placed at the front.

Figure 4 relates to a method of canceling cooperative driving in the first mode. As described above, the forward separation distance (Df), which is the distance between the best vehicle 430, which is the leader vehicle, and the other vehicle 482 in front of it, is the front separation distance (Df). This is a case where the rear separation distance Dr, which is the distance between the last vehicle 450 and the other vehicle 484 behind it, is more than the rear threshold.

When cooperative driving cancellation is initiated in this first mode state, the cooperative driving cancellation request generator 320 included in the leader vehicle determines the central vehicle as the reference vehicle 410.

Then, for the first front vehicle 420 immediately ahead of the reference vehicle 410, a ₁ = 2 Δs using the preset safety relative distance △s and cooperative driving release period t0 value as shown in Equation 1. /t Generate and transmit a cooperation release request message including an acceleration command indicating an acceleration of ₀ and an identifier of the first vehicle ahead (420).

In addition, for the best vehicle 420, which is the second front vehicle and the leader vehicle, an acceleration command indicating an acceleration of a ₂ = 4△s/t ₀ as shown in Equation 1 and an identifier of the corresponding best vehicle 410 are provided. A cooperation release request message can be created and transmitted.

Of course, in the case of FIG. 4, the second front vehicle and best vehicle 420 is the leader vehicle itself, so in this case, it is sufficient to accelerate using the calculated acceleration (a ₂ = 4△s/t ₀ ), and separate cooperation There is no need to send a release request message to the following vehicle.

In addition, the cooperative driving release request generator 320 includes a headway time increase command determined according to Equation 2 and an identifier of the vehicle for the two rear vehicles 440 and 450 disposed behind the reference vehicle. A cooperation release request message can be created and transmitted.

Of course, as described above, in order to sequentially increase the distance between vehicles, cooperation release request messages may be sequentially transmitted, or cooperation release request messages with different release operation start time information may be transmitted for each follower vehicle.

By this control, as shown in (b) of FIG. 4, at the time when the cooperative driving cancellation period has elapsed (t+t ₀ ), the inter-vehicle distance with respect to the reference vehicle 410 increases from the initial Sr to Sr'( =Sr+△s), the release of cooperative driving is completed, so that the release of cooperative driving can be performed safely.

Figure 5 relates to a cooperative driving release method in the second mode. As described above, the forward separation distance (Df), which is the distance between the best vehicle 530, which is the leader vehicle, and the other vehicle 582 in front of it, is the front separation distance (Df). This is a case where the rear separation distance Dr, which is the distance between the last vehicle 550 and the rear vehicle 584 behind it, is greater than or equal to the rear threshold.

When cancellation of cooperative driving is initiated in this second mode state, the cooperative driving cancellation request generator 320 included in the leader vehicle determines according to Equation 2 for all rear follower vehicles based on itself as the best vehicle. A cooperation release request message containing a headway time increase command and the identifier of the vehicle is generated and transmitted.

Of course, as described above, in order to sequentially increase the distance between vehicles, cooperation release request messages may be sequentially transmitted, or cooperation release request messages with different release operation start time information may be transmitted for each follower vehicle.

By this control, as shown in (b) of FIG. 5, at the time when the cooperative driving release period has elapsed (t+t ₀ ), the inter-vehicle distance is changed from the initial Sr to Sr'( =Sr+△s), the release of cooperative driving is completed, so that the release of cooperative driving can be performed safely.

Figure 6 relates to a method of canceling cooperative driving in the third mode. As described above, the forward separation distance (Df), which is the distance between the best vehicle 630, which is the leader vehicle, and the other vehicle 682 in front of it, is the front separation distance (Df). This is the case where the rear separation distance Dr, which is the distance between the last vehicle 650 and the other vehicle 684 behind it, is also less than the rear threshold.

When cooperative driving cancellation is initiated in this third mode, the cooperative driving cancellation request generator 320 included in the leader vehicle detects other vehicles existing in the adjacent lane.

In Figure 6, in the left adjacent lane of the cooperative driving lane, there are two left other vehicles (692, 692') spanning the entire cooperative driving area, and in the right adjacent lane, there is one right other vehicle (694) at the front of the cooperative driving area. Assume that exists.

In this case, the cooperative driving release request generation unit 320 included in the leader vehicle makes it impossible for all follower vehicles to change lanes to the adjacent left lane, and only the two follower vehicles 6.40 and 6.50 present at the rear among the follower vehicles are allowed. You can confirm that you can safely change lanes to the right.

Accordingly, the cooperative driving cancellation request generator 320 included in the leader vehicle sends a cooperation cancellation request including a right lane change command and the identifier of the vehicle to the two follower vehicles 640 and 650 located at the rear among the follower vehicles. Create and send a message.

Through this control, as shown in (b) of FIG. 6, at the time when the cooperative driving release period has elapsed (t+t ₀ ), the two follower vehicles 640 and 650 located at the rear are in the cooperative driving state. You will leave safely.

Of course, in this case, the remaining three vehicles still maintain the cooperative driving state, and by repeating the above-described cooperative driving release process again after a certain period of time, the entire group of vehicles can deviate from cooperative driving.

Meanwhile, the cooperative driving release request generator 320 included in the leader vehicle determines that the front separation distance (Df) and the rear separation distance (Dr) are less than the front threshold and the rear threshold, respectively, and the adjacent lane is located throughout the entire cooperative driving area. If it is determined that lane change to an adjacent lane is impossible due to the presence of other vehicles in the cooperative driving group, a cooperative driving cancellation request including a cooperative driving cancellation pending command can be generated and transmitted to all follower vehicles included in the cooperative driving group.

Figure 7 is an overall flowchart of the cooperative driving release method according to the present invention.

The cooperative driving release method according to the present invention is a method of controlling release from cooperative driving in which vehicles in a cooperative driving group including a leader vehicle and two or more follower vehicles drive cooperatively, and includes a cooperative driving control device included in the leader vehicle ( 300).

As shown in FIG. 7, in the method for canceling cooperative driving according to the present invention, first, the cooperative driving control device 300 included in the leader vehicle determines to start canceling cooperative driving (S710);

Next, the cooperative driving control device 300 determines the front separation distance (Df) between the best vehicle and the front other vehicle existing in front of the best vehicle in the cooperative driving group, and the rear vehicle present behind the last vehicle in the cooperative driving group. After detecting the rear separation distance (Dr) between the vehicle and the last vehicle, the front separation distance and the rear separation distance are compared to the front threshold and rear threshold, respectively. (S720)

Next, the cooperative driving control device 300 generates different cooperative driving release requests for each of the first to third modes depending on whether the front and rear separation distances exceed the front and rear thresholds, respectively. (S730)

At this time, the cooperative driving release request may include an acceleration command, a headway time increase command, a lane change command, etc. for each mode, and may further include identification information of the following vehicle for which the command is to be performed.

The cooperative driving control device 300 transmits the generated cooperative driving release request to the corresponding follow vehicle (S740).

The follower vehicle that receives the request to cancel cooperative driving cooperates by operating the engine control, braking control, and steering control systems included in its own vehicle according to the commands (acceleration, headway increase, lane change) included in the cooperation release request message. Perform a driving release operation.

Figure 8 is a flowchart illustrating in detail the cooperative driving release process for each mode according to an embodiment of the present invention.

As shown in FIG. 8, when cooperative driving is canceled, the cooperative driving control device 300 included in the leader vehicle determines the rear separation distance (Dr) between the last vehicle and the other rear vehicle present behind the last vehicle in the cooperative driving group. After making the decision, it is compared with a preset posterior threshold (S810).

If the rear separation distance (Dr) is greater than the rear threshold, check whether the front separation distance (Df) between the best vehicle and other vehicles in front that exist in front of the best vehicle in the cooperative driving group is greater than the front threshold. (S820 )

If both the front separation distance (Df) and the rear separation distance (Dr) are greater than the front threshold and the rear threshold, the cooperative driving release process by the first mode is entered, and an acceleration command is given to the vehicle in front of the reference vehicle, A headway time increase command is executed and controlled for vehicles behind the reference vehicle (S830).

Meanwhile, in step S810, if the rear separation distance (Dr) is less than the rear threshold, it is determined whether there are other vehicles in the adjacent lane of the cooperative driving area (S850), and even if there are no other vehicles or other vehicles in the adjacent lane, some following vehicles If lane change is possible, the third mode is entered and control is performed so that a lane change command is performed for the following vehicle (S860).

In steps S810 and S820, if it is determined that the rear separation distance (Dr) is greater than the rear threshold but the front separation distance (Df) is smaller than the front threshold, the cooperative driving release process by the second mode is entered, A headway time increase command is executed and controlled for all vehicles present behind the best vehicle (S840).

In addition, if both the front separation distance (Df) and the rear separation distance (Dr) are less than the corresponding threshold and other vehicles exist in the adjacent lane and lane change is not possible, release of cooperative driving is suspended and terminated (S870).

Meanwhile, the present invention is not limited to the above-described first to third modes. For example, when the front separation distance (Df) is more than the front threshold and the rear separation distance (Dr) is less than the rear threshold, an additional method is provided. It can also operate in 4 modes.

In this fourth mode, the reference vehicle is set as the last vehicle, and a cooperative driving release message including a different acceleration command can be generated and transmitted to the front following vehicle according to Equation 1.

That is, in FIG. 8, it is explained that if the rear separation distance (Dr) is less than the rear threshold in step S810, the decision step of applying the third mode is immediately entered. However, if the rear separation distance (Dr) is less than the rear threshold in step S810, It may re-determine whether the front separation distance (Df) is more than the front threshold, and if the front separation distance (Df) is more than the front threshold, it may operate in the additional fourth mode as above.

According to the above-described embodiment of the present invention, the front separation distance (Df) between the other vehicle in front and the best vehicle in front of the best vehicle in the cooperative driving group at the time of canceling cooperative driving, and the distance behind the last vehicle in the cooperative driving group By applying different cooperative driving cancellation methods for each mode depending on the size of the rear separation distance (Dr) between the remaining rear vehicle and the last vehicle, the cooperative driving state can be safely released while excluding the possibility of collision with the front and rear vehicles. There is a possible effect.

The above description and attached drawings are merely illustrative of the technical idea of the present invention, and those skilled in the art will be able to combine the components without departing from the essential characteristics of the present invention. , various modifications and transformations such as separation, substitution, and change will be possible. Accordingly, the embodiments disclosed in the present invention are not intended to limit the technical idea of the present invention, but are for illustrative purposes, and the scope of the technical idea of the present invention is not limited by these embodiments. The scope of protection of the present invention should be interpreted in accordance with the claims below, and all technical ideas within the equivalent scope should be construed as being included in the scope of rights of the present invention.

Claims (14)

A cooperative driving control device disposed inside the leader vehicle to control cooperative driving in which vehicles in a cooperative driving group including a leader vehicle and one or more follower vehicles drive cooperatively, comprising:
At the time of canceling cooperative driving, the forward separation distance between the other vehicles in front and the best vehicle in the cooperative driving group, and the distance between the other vehicles in the rear and the last vehicle in the cooperative driving group, a front-to-rear distance determination unit that detects the rear separation distance;
a cooperative driving cancellation request generating unit that generates different cooperative driving cancellation requests depending on whether the front separation distance and the rear separation distance exceed a front threshold and a rear threshold, respectively;
a cooperative driving cancellation request transmission unit that transmits the cooperative driving cancellation request uniquely generated for each following vehicle to the following vehicle;
Including,
The cooperative driving release request includes one of an acceleration command, a headway distance increase command, a headway time increase command, and a lane change command corresponding to each of the following vehicles,
The acceleration command is performed for the i-th front vehicle located in front of the reference vehicle in the central area among the vehicles included in the cooperative driving group, the acceleration, safety relative distance, and cooperative driving release of the i-1th front vehicle. A cooperative driving control device characterized in that it instructs to have an acceleration calculated by a mathematical equation using the period as a parameter. According to paragraph 1,
In the case of the first mode in which the front separation distance and the rear separation distance exceed the front threshold and the rear threshold, respectively, the cooperative driving release request generator includes an acceleration command for the follower vehicle ahead of the reference vehicle. A cooperative driving control device characterized in that it generates a cooperative driving cancellation request, and generates a cooperative driving cancellation request including a headway distance increase command or a headway time increase command for a follower vehicle rearward than the reference vehicle. According to paragraph 2,
In the case of a second mode in which the front separation distance is less than the front threshold and the rear separation distance exceeds the rear threshold, the cooperative driving release request generator excludes the best vehicle among the vehicles included in the cooperative driving group. A cooperative driving control device characterized in that it generates a cooperative driving release request including a headway distance increase command or a headway time increase command for all rear following vehicles. According to paragraph 3,
In the case of the third mode where the front separation distance and the rear separation distance are less than the front threshold and the rear threshold, respectively, the cooperative driving release request generating unit detects another vehicle in the adjacent lane of the cooperative driving lane, and then operates in the adjacent lane. If there is no other vehicle in the cooperative driving group, a cooperative driving control device generating a cooperative driving release request including a lane change command for one or more follower vehicles included in the cooperative driving group. According to paragraph 4,
A mathematical equation using the acceleration of the i-1th front vehicle, a safe relative distance, and a cooperative driving release period as parameters is comprised of the following equation.
a _i =a _i-1 +2△s/t ₀
Here, ai is the acceleration of the ith front vehicle, △s is the safe relative distance, and t0 is the cooperative driving release period. According to clause 5,
In the case of the first mode, the headway time increase command includes a headway time according to the equation below for a rear vehicle disposed behind the reference vehicle.
HWr = (Sr+△s)/V _L
where HWr is the headway time for the vehicle behind, △s is the safety relative distance, V _L is the best vehicle speed at the start of cooperative driving cancellation. According to clause 6,
In the case of the second mode, the headway time increase command includes the headway time according to the equation below for all rear follower vehicles arranged behind the best vehicle.
HWr = (Sr+△s)/V _L
where HWr is the headway time for the rear following vehicle, △s is the safe relative distance, V _L is the vehicle speed of the leader vehicle at the start of cooperative driving cancellation. According to paragraph 4,
The cooperative driving cancellation request generating unit generates a cooperative driving cancellation request including a cooperative driving cancellation pending command for all follow vehicles included in the cooperative driving group when another vehicle exists in the adjacent lane. Driving control device. According to paragraph 1,
It further includes a wireless communication unit that receives identification information and driving information of the follower vehicle from the follower vehicle,
The wireless communication unit is a cooperative driving control device characterized in that it receives information about the front separation distance and the rear separation distance from the first vehicle and the last vehicle. A device for controlling cooperative driving in which vehicles in a cooperative driving group including a leader vehicle and one or more follower vehicles drive cooperatively, comprising:
The front separation distance between the leading vehicle and the other vehicle in front that exists in the leader vehicle and is in front of the best vehicle in the cooperative driving group at the time of release of cooperative driving, and the rear vehicle that exists behind the last vehicle in the cooperative driving group Detect the rear separation distance between the vehicle and the last vehicle, and generate and transmit different cooperative driving release requests to the following vehicle depending on whether the front separation distance and the rear separation distance exceed the front threshold and rear threshold, respectively. a cooperative driving master control device;
A cooperative driving slave control device included in the follower vehicle and receiving a cooperative driving release request from the cooperative driving control device of the leader vehicle and then changing the vehicle driving state to cancel cooperative driving accordingly;
Including,
The cooperative driving release request includes one of an acceleration command, a headway distance increase command, a headway time increase command, and a lane change command corresponding to each of the following vehicles,
The acceleration command is performed for the i-th front vehicle located in front of the reference vehicle in the central area among the vehicles included in the cooperative driving group, the acceleration, safety relative distance, and cooperative driving release of the i-1th front vehicle. A cooperative driving control device characterized in that it instructs to have an acceleration calculated by a mathematical equation using the period as a parameter. A method for controlling release from cooperative driving in which vehicles in a cooperative driving group including a leader vehicle and one or more follower vehicles drive cooperatively, comprising:
It is performed using a cooperative driving master device included in the leader vehicle,
A first step of deciding to initiate cooperative driving release;
Detects the forward separation distance between the first vehicle and the other vehicle in front of the last vehicle in the cooperative driving group, and the rear separation distance between the last vehicle and the other vehicle in the rear that exists behind the last vehicle in the cooperative driving group. The second step is to do;
A third step of generating different cooperative driving release requests depending on whether the front separation distance and the rear separation distance exceed a front threshold and a rear threshold, respectively;
A fourth step of transmitting the cooperative driving cancellation request uniquely generated for each follow vehicle to the follow vehicle;
Including,
The cooperative driving release request includes one of an acceleration command, a headway distance increase command, a headway time increase command, and a lane change command corresponding to each of the following vehicles,
The acceleration command is performed for the i-th front vehicle located in front of the reference vehicle in the central area among the vehicles included in the cooperative driving group, the acceleration, safety relative distance, and cooperative driving release of the i-1th front vehicle. A cooperative driving control method characterized by instructing to have an acceleration calculated by a mathematical equation using the period as a parameter. According to clause 11,
In the second step, in the case of the first mode in which the front separation distance and the rear separation distance exceed the front threshold and the rear threshold, respectively, an acceleration command is included for the follower vehicle ahead of the reference vehicle. A cooperative driving control method comprising generating a cooperative driving release request and generating a cooperative driving release request including a headway distance increase command or a headway time increase command for a follower vehicle rearward of the reference vehicle. According to clause 12,
In the second step, in the case of the second mode in which the front separation distance is less than the front threshold and the rear separation distance exceeds the rear threshold, the headway distance is set for all follow vehicles included in the cooperative driving group. A cooperative driving control method characterized by generating a cooperative driving release request including an increase command or a headway time increase command. According to clause 13,
In the second step, in the case of the third mode where the front separation distance and the rear separation distance are less than the front threshold and the rear threshold, respectively, after detecting another vehicle in the adjacent lane of the cooperative driving lane, A cooperative driving control method characterized in that, when no other vehicle exists, a cooperative driving release request including a lane change command is generated for one or more follower vehicles included in the cooperative driving group.

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