KR101790076B1 - Method for active roll preview control with vehicle-to-vehicle communication - Google Patents

Abstract

An active roll preview control method using inter-vehicle communication according to an embodiment includes: a preceding vehicle information obtaining step of obtaining lateral acceleration information and position information of a preceding vehicle in a preceding vehicle; A position-based lateral acceleration information transmission step of obtaining the position-based lateral acceleration information by combining the lateral acceleration information and the positional information of the preceding vehicle and transmitting the position-based lateral acceleration information to the following vehicle using wireless communication; A trailing vehicle information acquiring step of acquiring the current speed of the trailing vehicle and the position information of the trailing vehicle in the trailing vehicle; Based lateral acceleration information and position information of the following vehicle based on the distance-based lateral acceleration information and the current vehicle speed of the following vehicle based on the distance-based lateral acceleration information and the current speed of the following vehicle, Time-based lateral acceleration information acquisition step of acquiring time-based lateral acceleration information by setting and interpolating the time-based lateral acceleration information; And a preview control performing step of performing active roll preview control using the time-based lateral acceleration information in the trailing vehicle.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a method of controlling an active roll for a vehicle,

The present invention relates to an active roll preview control method using inter-vehicle communication.

Over the past decade, widespread deployment of SUVs with high center of gravity has increased vehicle rollover accidents. Most of the car rollovers are fatal because of the high proportion of abalone occupation in a fatal accident. Over the past eight years, the total number of deaths due to vehicle overturns has decreased from 36.3% to 33.7% in all traffic accidents, but vehicle overtaking still accounts for a large proportion of passenger car deaths.

Vehicle rollover is caused by lateral acceleration caused by excessive steering at high speed. Therefore, it is necessary to reduce the lateral acceleration to prevent the vehicle from overturning. Various methods have been proposed for this purpose. Among them, the most common method is to make the vehicle under-steer by reducing the reference rate or the vehicle speed using differential braking, but the reduction of the reference rate is caused by the collision or obstacle It can cause another accident such as vehicle overturn. Another method is to use an active suspension device or an active anti-roll bar to reduce the influence of lateral acceleration on the rolling motion of the vehicle under the assumption that the lateral acceleration is disturbance that can not be controlled. However, The inner wheel is heard, and as a result, the tire lateral force of the outer front wheel becomes sharply larger than that of the outer rear wheel, so that the vehicle can be rotated around the outer front wheel.

Active Roll Control, which controls the rolling motion of a vehicle using an active throttle stick or active anti roll bar, has been designed using a feedback controller. In contrast, if the lateral acceleration information causing the roll motion can be known in advance, the preview control combining the feedback controller and the feedforward controller can be performed to further improve the control performance. However, until now there has been no way to know in advance the lateral acceleration information that is applied to the vehicle.

Recently, various communication can be performed due to the development of inter-vehicle communication using wireless communication. As shown in FIG. 18, when the vehicles are running in a row in a cluster, the performance of the existing controller can be further improved if information on the preceding vehicle is transmitted to the trailing vehicle using wireless communication.

Korean Patent Publication No. 10-2013-0102240

An embodiment of the present invention is to provide an active roll preview control method using inter-vehicle communication that allows the trailing vehicle to perform preview control by transmitting the lateral acceleration information of the preceding vehicle to the trailing vehicle in a situation where the vehicles are running in a line .

An active roll preview control method using inter-vehicle communication according to an embodiment includes: a preceding vehicle information obtaining step of obtaining lateral acceleration information and position information of a preceding vehicle in a preceding vehicle; Based lateral acceleration information obtained by combining the lateral acceleration information and the positional information of the preceding vehicle in the preceding vehicle and transmitting the position-based lateral acceleration information to the following vehicle using wireless communication, Information transmission step; A trailing vehicle information acquiring step of acquiring the current speed of the trailing vehicle and the position information of the trailing vehicle in the trailing vehicle; Based on the positional information of the position-based lateral acceleration information and the position information of the trailing vehicle in the trailing vehicle, and combines the calculated distance information with the transmitted position-based lateral acceleration information to calculate a distance Based on the distance information of the lateral acceleration information based on the distance information of the trailing vehicle based on the current speed of the trailing vehicle and multiplying the current speed of the trailing vehicle by points of the same time interval to obtain distance information of the equal distance, Based lateral acceleration information by linearly interpolating the distance-based lateral acceleration information based on the time-based lateral acceleration information, And a preview control performing step of performing active roll preview control using the time-based lateral acceleration information in the trailing vehicle.

Here, the position information of the preceding vehicle and the position information of the following vehicle can be obtained using a global positioning system (GPS).

Here, the wireless communication may be performed according to the sampling rate of the GPS.

Here, the wireless communication may be a WAVE (Wireless Access in Vehicular Environment) communication.

Here, in the preceding vehicle information acquiring step, the lateral acceleration information may be obtained using the lateral acceleration sensor.

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According to the active roll predictive control method using inter-vehicle communication according to the embodiment, the trailing vehicle receives the lateral acceleration information and the positional information of the preceding vehicle to obtain the lateral acceleration based on the distance, Information is obtained and the active roll preview control is performed, so that the performance of the roll control can be improved and the ride comfort of the following vehicle can be improved.

According to the active roll predictive control method using the inter-vehicle communication according to the embodiment, since the position information is obtained using the GPS (Global Positioning System), position information can be obtained more accurately and quickly.

According to the active roll predictive control method using inter-vehicle communication according to the embodiment, since the radio communication is performed in accordance with the GPS sampling rate, the active roll predictive control can be optimized.

According to the active roll predictive control method using the inter-vehicle communication according to the embodiment, since the wireless communication is WAVE (Wireless Access in Vehicular Environment) communication, the information of the preceding vehicle can be smoothly transmitted between vehicles moving at a high speed.

According to the active roll predictive control method using inter-vehicle communication according to the embodiment, since the lateral acceleration information is obtained by using the lateral acceleration sensor, the lateral acceleration information can be obtained more accurately.

1 is an example of wireless communication.
2 is a view for explaining active roll control.
3 is a conceptual diagram of an active roll preview control method using inter-vehicle communication according to the embodiment.
4 is a flowchart of an active roll preview control method using inter-vehicle communication according to the embodiment.
5 is a graph for explaining an example of linear interpolation.
Figs. 6 to 8 are graphs showing the results at a speed of 80 km / h.
9 to 11 are graphs showing the results when the speed is increased from 80 km / h to 100 km / h.
12 to 14 are graphs showing the results when the speed is lowered from 80 km / h to 60 km / h.
15 to 17 are graphs showing the results when the speed is further lowered from 80 km / h to 40 km / h.
18 is an actual photograph of a vehicle community traveling.

The following detailed description refers to the accompanying drawings which illustrate, by way of example, specific embodiments in which the invention may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the invention. It should be understood that the various embodiments of the present invention may be different but need not be mutually exclusive. For example, certain features, structures, and characteristics described herein may be implemented in other embodiments without departing from the spirit and scope of the invention in connection with one embodiment. It is also to be understood that the location or arrangement of the individual components within each disclosed embodiment may be varied without departing from the spirit and scope of the present invention. The following detailed description is, therefore, not to be taken in a limiting sense, and the scope of the present invention is to be limited only by the appended claims, along with the full scope of equivalents to which such claims are entitled, if properly explained. In the drawings, like reference numerals refer to the same or similar functions throughout the several views.

<Embodiment>

1 is an example of wireless communication.

Referring to FIG. 1, information in an intelligent transportation system (ITS) environment can be shared among vehicles through wireless communication or the like. Here, the wireless communication may be a WAVE (Wireless Access in Vehicular Environment) communication. Wireless communication is a wireless communication technology in which a vehicle can exchange vehicle-to-vehicle (V2V) or vehicle-to-infrastructure (V2I) packet frames between a vehicle and an infrastructure in a high-speed mobile environment. / g It is a communication technology that improves the wireless LAN technology to the vehicle environment.

Specifically, each vehicle includes a vehicle antenna 110, 120, a terminal platform 210, 220, and a vehicle communication module 310, 320, and the infrastructure includes an infrastructure An infrastructure antenna 400 and an infrastructure communication module 500.

 2 is a view for explaining active roll control. Specifically, Fig. 2 is a one-degree-of-freedom roll model simulating the roll motion of a vehicle.

The active roll control is controlled by the active roll controller, and specifically controls the roll motion of the vehicle using the active suspension and the active anti-roll bar. In the embodiment, a linear quadratic regulator (LQR) or a linear quadratic (LQ) optimal predictive controller design methodology is applied when designing an active roll controller.

Referring to FIG. 2, the roll motion is affected by lateral acceleration. At this time, the roll motion can be controlled by the active roll control. Here, m _s is a vehicle spring, the mass (vehicle sprung mass) and, a _y is the lateral acceleration (lateral acceleration), M _φ can control the roll moment (control roll moment), φ is the roll angle (roll angle), h _s is CG is the height of CG from the roll axis, g is the gravitational acceleration constant, and I _x is the roll moment of inertia.

Therefore, if the information about the lateral acceleration is known in advance, the active roll predictive control capable of further reducing the roll motion than the active roll control can be performed.

Hereinafter, an active roll preview control method using inter-vehicle communication according to the embodiment will be described.

When the vehicles are running in line, the information of the preceding vehicle can be transmitted to the trailing vehicle (s) through wireless communication. Thus, the trailing vehicle (s) can perform active roll preview control through the information of the preceding vehicle as follows.

3 is a conceptual diagram of an active roll preview control method using inter-vehicle communication according to the embodiment.

Referring to Fig. 3, the trailing vehicle 20 receives information of the preceding vehicle from the preceding vehicle 10. Fig. Specifically, the preceding vehicle 10 can obtain the lateral acceleration information. At this time, the lateral acceleration information is obtained based on the time base (t _k , a _{y, k} ). However, since the time information is changed in a situation where the vehicle speed changes, it can not be used for the preview control that assumes a constant time interval. Therefore, the preceding vehicle 10 combines the lateral acceleration information t _k , a _{y, k} with the position information of the preceding vehicle 10 to obtain the position-based lateral acceleration information X _k , Y _k , a _y, And transmits the position-based lateral acceleration information (X _k , Y _k , a _{y, k} ) to the trailing vehicle 20. At this time, since the trailing vehicle 20 operates in accordance with the information of the preceding vehicle 10, the trailing vehicle 20 can be operated in the same manner as the preceding vehicle 10 without any additional control of the trailing vehicle 20. [ Here, the preceding vehicle 10 and the following vehicle 20 may be vehicles that run in a cluster.

3, the preceding vehicle 10 and the following trailing vehicle 20 are shown as being composed of one preceding vehicle 10 and one trailing vehicle 20. However, in the active roll preview control method using inter-vehicle communication according to the embodiment, It may be composed of the vehicle 10 and two or more trailing vehicles 20.

4 is a flowchart of an active roll preview control method using inter-vehicle communication according to the embodiment.

3 and 4, an active roll preview control method using inter-vehicle communication according to an embodiment includes a preceding vehicle information obtaining step S100, a position-based lateral acceleration information transmitting step S200, a trailing vehicle information obtaining step (S300), a time-based lateral acceleration information acquisition step (S400), and a preview control execution step (S500).

The preceding vehicle information acquiring step (S100) acquires the lateral acceleration information and the position information of the preceding vehicle (10) in the preceding vehicle (10). More specifically, the lateral acceleration information of the preceding vehicle 10 can be obtained from the lateral acceleration sensor mounted on the preceding vehicle 10. [ The lateral acceleration obtained in the preceding vehicle 10 can be transmitted to the trailing vehicle 20 using wireless communication. The position information of the preceding vehicle 10 can be obtained through a GPS (Global Positioning System) or the like.

The position-based lateral acceleration information transmission step (S200) obtains the position-based lateral acceleration information by combining the lateral acceleration information and the position information, and transmits the position-based lateral acceleration information to the following vehicle 20 using wireless communication .

The trailing vehicle information acquiring step S300 acquires the current speed of the trailing vehicle 20 and the position information of the trailing vehicle 20 in the trailing vehicle 20. Specifically, the current speed of the trailing vehicle 20 is measured in the vehicle body of the trailing vehicle 20 and can be obtained through a CAN (Controller Area Network) of the vehicle network, and the position information of the trailing vehicle 20 can be obtained through a GPS Can be obtained.

The time-based lateral acceleration information acquisition step (S400) acquires the time-based lateral acceleration information using the position-based lateral acceleration information transmitted from the preceding vehicle (10) and the position information of the following vehicle (20). Specifically, distance information is calculated using the position information of the preceding vehicle 10 and the position information of the following vehicle 20 in the position-based lateral acceleration information transmitted from the preceding vehicle 10. Specifically, the position-based lateral acceleration information transmitted from the preceding vehicle 10 to the following vehicle 20 is transmitted in the form of (X, Y, a _y ). Where X and Y are the GPS latitude and longitude, respectively. If (X, Y, a _y ) is sent from the preceding vehicle 10 to the following vehicle 20 at predetermined intervals, (X, Y) forms a path. Assuming that the trailing vehicle 20 follows this route, the distance on the route from the current position of the trailing vehicle 20 to (X, Y) can be easily obtained. Based on the position-based lateral acceleration information transmitted from the preceding vehicle 10, the lateral acceleration information and the distance information are combined to obtain the distance-based lateral acceleration information, and the distance-based lateral acceleration information and the current speed of the following vehicle 20 are used And sets the distance information at equal intervals and interpolates to obtain time-based lateral acceleration information. Here, the interpolation may be linear interpolation.

The preview control execution step S500 carries out the active roll preview control using the time-based lateral acceleration information in the following vehicle 20.

As described above, in the active roll predictive control method using the inter-vehicle communication according to the embodiment, the trailing vehicle 20 receives the lateral acceleration information and the positional information of the preceding vehicle 10 to obtain the lateral acceleration based on the distance, Based on the time-based lateral acceleration information, the performance of the active roll control can be improved and the ride comfort of the following vehicle 20 can be improved.

In addition, since the position information of the preceding vehicle and the position information of the preceding vehicle in the active roll preview control method using the inter-vehicle communication according to the embodiment are obtained by using the GPS (Global Positioning System), the position information of the corresponding vehicle can be obtained more accurately and quickly Can be obtained.

Further, in the active roll predictive control method using inter-vehicle communication according to the embodiment, since the lateral acceleration information is obtained by using the lateral acceleration sensor, the lateral acceleration information can be obtained more accurately.

Here, since the sampling rate of the GPS is slower than the speed of the wireless communication, the wireless communication can be performed according to the sampling rate of the GPS. For example, wireless communication may be performed at a sampling rate of 100 ms, which is a GPS.

As described above, since the radio communication of the active roll preview control method using inter-vehicle communication according to the embodiment is performed in accordance with the GPS sampling rate, the active roll preview control can be optimized.

Here, the wireless communication may be a WAVE (Wireless Access in Vehicular Environment) communication.

As described above, since the wireless communication of the active roll preview control method using the inter-vehicle communication according to the embodiment is WAVE (Wireless Access in Vehicular Environment) communication, the information of the preceding vehicle can be smoothly transmitted between the vehicles moving at a high speed.

5 is a graph for explaining an example of linear interpolation. The horizontal axis in FIG. 5 is the distance and the vertical axis is the lateral acceleration (a _y ).

5, a lateral acceleration information of distance-based _{(d 1, d 2, d} 3, d 4, d 5, d 6) based on p _1, the distance information, such as the distance (in the p _2, p _3, p ₄ , p ₅ , p ₆ , p ₇ , p ₈ ) can be used to obtain equidistant time-based lateral acceleration information.

At this time, the distance information of the equal interval can be summarized by the following equation (1).

[Equation 1]

Where v _x (k) is the current speed of the trailing vehicle, and [0 T _S 2T _S 3T _S ...] are points at the same time interval. In this way, the trailing vehicle 20 of the current velocity (v _x (k)), the same time interval of points _([S 0 T 2T 3T _{S S} ...]) multiplied by the distance information including distance (p _1, p of the _{2, p 3, p 4,} p 5, p 6, p 7, p 8) the distance information then obtained, such as distance _{(p 1, p 2, p} 3, p 4, p 5, p 6, p 7 , p ₈ ) can be linearly interpolated to obtain time-based lateral acceleration information.

Equation (1) relates to a motion equation, a state space equation, an LQR controller, and an LQ preview controller of a one-degree-of-freedom roll model.

Figs. 6 to 8 are graphs showing the results at a speed of 80 km / h. Specifically, the horizontal axis in FIGS. 6 to 8 is time, the vertical axis in FIG. 6 is the roll angle, the vertical axis in FIG. 7 is the roll rate, and the vertical axis in FIG. (Control Input).

6 to 8, active roll predictive control (LQ Preview) is compared with no control (No Control), active roll control (LQR: linear quadratic regulator) and active roll predictive control It can be seen that the roll angle and the roll rate can be reduced compared to the case of no control. Also, it can be seen that the active roll control (LQ Preview) can reduce the roll angle and the roll rate than the active roll control (LQR).

Therefore, when the vehicle is moved at a constant speed, the active roll predictive control (LQ Preview) has better roll control performance than the no control (No Control) and the active roll control (LQR).

9 to 11 are graphs showing the results when the speed is increased from 80 km / h to 100 km / h. Specifically, the horizontal axis in Figs. 9 to 11 is time, the vertical axis in Fig. 9 is the vehicle velocity, the vertical axis in Fig. 10 is the roll angle, and the vertical axis in Fig. (Roll Rate).

10 and 11, when the active roll control (LQR) and the active roll preview control (LQ Preview) are compared with each other, the active roll preview control (LQ Preview) It can be seen that the roll angle and the roll rate can be reduced compared to the No Control. Also, it can be seen that the active roll control (LQ Preview) can reduce the roll angle and the roll rate than the active roll control (LQR).

Therefore, even if the vehicle speed is increased, the active roll predictive control (LQ Preview) has better roll control performance than the no control (No Control) and the active roll control (LQR).

12 to 14 are graphs showing the results when the speed is lowered from 80 km / h to 60 km / h. Specifically, the horizontal axis in Figs. 12 to 14 is time, the vertical axis in Fig. 12 is the vehicle velocity, the vertical axis in Fig. 13 is the roll angle, and the vertical axis in Fig. (Roll Rate).

13 and 14, when the active roll control (LQR) and the active roll preview control (LQ Preview) are compared with each other, the active roll preview control (LQ Preview) It can be seen that the roll angle and the roll rate can be reduced compared to the No Control. Also, it can be seen that the active roll control (LQ Preview) can reduce the roll angle and the roll rate than the active roll control (LQR).

Therefore, the active roll predictive control (LQ Preview) has better roll control performance than the no control (No Control) and the active roll control (LQR), even when the vehicle speed decreases.

15 to 17 are graphs showing the results when the speed is further lowered from 80 km / h to 40 km / h. Specifically, the horizontal axis in FIGS. 15 to 17 is time, the vertical axis in FIG. 15 is the vehicle velocity, the vertical axis in FIG. 16 is the roll angle, and the vertical axis in FIG. (Roll Rate).

16 and 17, when the active roll control (LQR) and the active roll preview control (LQ Preview) are compared with each other, the active roll preview control (LQ Preview) It can be seen that the roll angle and the roll rate can be reduced compared to the No Control. Also, it can be seen that the active roll control (LQ Preview) can reduce the roll angle and the roll rate than the active roll control (LQR).

Therefore, the active roll predictive control (LQ Preview) has better roll control performance than the no control (No Control) and the active roll control (LQR) even when the vehicle speed is further reduced.

As described above, the active roll preview control method using inter-vehicle communication according to the embodiment has good roll control performance not only when the speed is constant, but also when the speed increases or decreases.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present invention as defined by the following claims It can be understood that The features, structures, effects and the like described in the embodiments are included in at least one embodiment of the present invention, and are not necessarily limited to only one embodiment. Furthermore, the features, structures, effects and the like illustrated in the embodiments can be combined and modified by other persons skilled in the art to which the embodiments belong. Therefore, it should be understood that the present invention is not limited to these combinations and modifications.

10: The preceding vehicle
20: Trailing vehicle
110, 120: Vehicle antenna
210, 220: Terminal Platform
310, 330: vehicle communication device

Claims (6)

A preceding vehicle information obtaining step of obtaining lateral acceleration information and position information of the preceding vehicle in the preceding vehicle;
Based lateral acceleration information obtained by combining the lateral acceleration information and the positional information of the preceding vehicle in the preceding vehicle and transmitting the position-based lateral acceleration information to the following vehicle using wireless communication, Information transmission step;
A trailing vehicle information acquiring step of acquiring the current speed of the trailing vehicle and the position information of the trailing vehicle in the trailing vehicle;
Based on the positional information of the position-based lateral acceleration information and the position information of the trailing vehicle in the trailing vehicle, and combines the calculated distance information with the transmitted position-based lateral acceleration information to calculate a distance Based on the distance information of the lateral acceleration information based on the distance information of the trailing vehicle based on the current speed of the trailing vehicle and multiplying the current speed of the trailing vehicle by points of the same time interval to obtain distance information of the equal distance, Based lateral acceleration information by linearly interpolating the distance-based lateral acceleration information based on the time-based lateral acceleration information, And
And performing a preview control of the active roll using the time-based lateral acceleration information in the trailing vehicle. The method according to claim 1,
Wherein the position information of the preceding vehicle and the position information of the trailing vehicle are obtained using GPS (Global Positioning System). 3. The method of claim 2,
Wherein the wireless communication is adapted to the sampling rate of the GPS. The method according to claim 1,
Wherein the wireless communication is WAVE (Wireless Access in Vehicular Environment) communication. The method according to claim 1,
Wherein the preceding vehicle information obtaining step obtains the lateral acceleration information using a lateral acceleration sensor. delete

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