KR102646251B1 - Autonomous emergency braking apparatus and control method thereof - Google Patents

Abstract

An automatic emergency braking device and its control method are disclosed. The automatic emergency braking device according to one aspect of the present invention includes a camera sensor unit that detects first object information by capturing a front image, a radar sensor unit that detects second object information through a laser, and a radar sensor unit that detects second object information through a laser, and While recognizing object information by fusing the first object information and the second object information detected by the radar sensor unit, if the deceleration of the target object is recognized in the first object information and the second object information, the first object information and a control unit that compares the difference between the second object information and the second object information with a preset constant value, and performs braking control based on the frame change rate of the target object detected by the camera sensor unit when the difference is greater than a certain value as a result of the comparison. do.

Description

Automatic emergency braking device and its control method {AUTONOMOUS EMERGENCY BRAKING APPARATUS AND CONTROL METHOD THEREOF}

The present invention relates to an automatic emergency braking device and a control method thereof. More specifically, the automatic emergency braking device operates normally for a dangerous object in front even when fusion information is lost due to a difference in information between the radar sensor unit and the camera sensor unit, It relates to an automatic emergency braking device and its control method that can prevent a collision with a dangerous object ahead.

In general, Autonomous Emergency Braking (AEB) predicts a collision with a preceding vehicle, two-wheeled vehicle, bicycle, obstacle, or pedestrian located in front of the control vehicle, determines the collision situation, and performs warning and automatic braking functions. It is a device that can minimize damage by avoiding or reducing damage.

Here, the automatic emergency braking system monitors the relative distance to the vehicle in front and the presence or absence of the vehicle ahead to determine when automatic emergency braking control will be activated and released. Radar and cameras are currently used as front vehicle monitoring sensors.

Meanwhile, if a dangerous situation occurs in which the preceding vehicle rapidly decelerates to the extent that it falls outside the range of the relative speed change rate that can be determined by the radar sensor, the radar sensor may incorrectly measure the longitudinal distance and relative speed of the preceding vehicle. In this case, the fused sensor information may be released due to differences in the longitudinal distance and relative speed of the preceding vehicle measured by the camera sensor. In this case, the automatic emergency braking system may no longer determine the preceding vehicle to be a dangerous object. As a result, the automatic emergency braking system may not operate properly in dangerous situations, and a collision with the preceding vehicle may occur.

Accordingly, there is a need to develop technology that allows automatic emergency braking to operate normally for dangerous objects ahead even when fusion information is lost due to information differences between radar sensors and camera sensors.

The background technology of the present invention is disclosed in Republic of Korea Patent Publication No. 10-1526622 (2015.06.08 notice, Method for preventing engine stop when operating automatic emergency braking system).

The present invention was created to improve the problems described above. The purpose of the present invention is to ensure that the automatic emergency braking device operates normally for dangerous objects in front even when fusion information is lost due to the information difference between the radar sensor unit and the camera sensor unit. , to provide an automatic emergency braking device and its control method that can prevent collisions with dangerous objects ahead.

The problem to be solved by the present invention is not limited to the problem(s) mentioned above, and other problem(s) not mentioned will be clearly understood by those skilled in the art from the description below.

The automatic emergency braking device according to one aspect of the present invention includes a camera sensor unit that detects first object information by capturing a front image, a radar sensor unit that detects second object information through a laser, and a radar sensor unit that detects second object information through a laser, and While recognizing object information by fusing the first object information and the second object information detected by the radar sensor unit, if the deceleration of the target object is recognized in the first object information and the second object information, the first object information and a control unit that compares the difference between the second object information and the second object information with a preset constant value, and performs braking control based on the frame change rate of the target object detected by the camera sensor unit when the difference is greater than a certain value as a result of the comparison. do.

In the present invention, if the difference between the first object information and the second object information is not greater than the predetermined value, the control unit may recognize the object information by fusing the first object information and the second object information. .

In the present invention, the control unit compares the frame change rate with a preset threshold, performs braking control if the frame change rate is greater than the threshold, and controls the first object information and the second object information if the frame change rate is not greater than the threshold. Object information can be recognized through fusion.

In the present invention, when the frame change rate is greater than or equal to the threshold, the controller compares the distance between the target object and the host vehicle with a preset distance limit value for each speed, and performs braking control when the distance limit value is within the corresponding distance limit value.

In the present invention, the first object information and the second object information include the distance and relative speed with the target object, and the target object may be one or more of a preceding vehicle and a pedestrian.

A control method of an automatic emergency braking device according to another aspect of the present invention includes the steps of a control unit receiving first object information detected by a camera sensor unit and second object information detected by a radar sensor unit, wherein the control unit receives the first object information detected by the radar sensor unit. If deceleration of the target object is recognized in the first object information and the second object information while recognizing object information by fusing the object information and the second object information, the difference between the first object information and the second object information is recognized. Comparing with a preset constant value, when the difference between the first object information and the second object information is more than a certain value, the control unit performs braking control based on the frame change rate of the target object detected by the camera sensor unit. It includes steps to:

The present invention provides the step of performing the braking control, wherein the control unit compares the frame change rate with a preset threshold, and the control unit performs braking control when the comparison result is greater than the threshold value. If not, the method may include recognizing the object information by fusing the first object information and the second object information.

In the present invention, when performing braking control when the frame change rate is above the threshold, the controller compares the distance between the target object and the host vehicle with a preset distance limit value for each speed, and when the frame change rate is above the threshold value, the control unit compares the distance between the object and the host vehicle with a preset distance limit value for each speed. Braking control can be performed.

In the present invention, when the difference between the first object information and the second object information is not more than a certain value, the control unit can recognize the object information by fusing the first object information and the second object information.

In the present invention, the first object information and the second object information include the distance and relative speed with the target object, and the target object may be one or more of a preceding vehicle and a pedestrian.

The lidar sensor control device and method according to one aspect of the present invention performs braking control based on the frame change rate of the object detected by the camera sensor unit when fusion information is lost due to the information difference between the radar sensor unit and the camera sensor unit. By doing so, a collision with a dangerous object ahead can be prevented.

A lidar sensor control device and method according to another aspect of the present invention unconditionally performs braking control based on the frame change rate of the object detected by the camera sensor unit when fusion information is lost due to an information difference between the radar sensor unit and the camera sensor unit. Rather, by performing braking control only when the distance between the target object recognized by the camera sensor unit and the own vehicle is within a certain distance, malfunction and sensitive operation of the automatic emergency braking device can be minimized.

Meanwhile, the effects of the present invention are not limited to the effects mentioned above, and various effects may be included within the range apparent to those skilled in the art from the contents described below.

1 is a block diagram showing an automatic emergency braking device according to an embodiment of the present invention.
Figure 2 is an example diagram to explain a case in which fusion is canceled due to an information difference between the radar sensor unit and the camera sensor unit according to an embodiment of the present invention.
Figure 3 is an example diagram for explaining distance limit values for each vehicle speed according to an embodiment of the present invention.
Figure 4 is a flowchart for explaining a control method of an automatic emergency braking device according to an embodiment of the present invention.
Figure 5 is a flowchart for explaining a control method of an automatic emergency braking device according to another embodiment of the present invention.

Hereinafter, an automatic emergency braking device and a control method thereof according to an embodiment of the present invention will be described with reference to the attached drawings. In this process, the thickness of lines or sizes of components shown in the drawing may be exaggerated for clarity and convenience of explanation.

In addition, the terms described below are terms defined in consideration of functions in the present invention, and may vary depending on the intention or custom of the user or operator. Therefore, definitions of these terms should be made based on the content throughout this specification.

Additionally, implementations described herein may be implemented as, for example, a method or process, device, software program, data stream, or signal. Although discussed only in the context of a single form of implementation (eg, only as a method), implementations of the features discussed may also be implemented in other forms (eg, devices or programs). The device may be implemented with appropriate hardware, software, firmware, etc. The method may be implemented in a device such as a processor, which generally refers to a processing device that includes a computer, microprocessor, integrated circuit, or programmable logic device. Processors also include communication devices such as computers, cell phones, portable/personal digital assistants (“PDAs”) and other devices that facilitate communication of information between end-users.

1 is a block diagram showing an automatic emergency braking device according to an embodiment of the present invention, and FIG. 2 illustrates a case in which fusion is canceled due to an information difference between the radar sensor unit and the camera sensor unit according to an embodiment of the present invention. FIG. 3 is an exemplary diagram for explaining a distance limit value for each vehicle speed according to an embodiment of the present invention.

Referring to FIG. 1, the automatic emergency braking device according to an embodiment of the present invention includes a camera sensor unit 110, a LiDAR sensor unit 120, a braking unit 140, and a control unit 130.

The camera sensor unit 110 captures a front image, detects first object information, and provides the detected first object information to the control unit 130. At this time, the camera sensor unit 110 can calculate the speed change rate based on the frame change rate of the captured image, and use the calculated speed change rate to detect the relative speed and position of the target object. Here, the first object information may include the longitudinal/lateral position of the target object, relative speed, object type information, etc., and the target object may be any one or more of a preceding vehicle and a pedestrian.

The radar sensor unit 120 radiates electromagnetic waves forward, detects second object information, and provides the detected second object information to the control unit 130. At this time, the second object information may include the longitudinal/lateral position of the target object, relative speed, acceleration, etc., and the target object may be one or more of a preceding vehicle and a pedestrian.

The braking unit 140 generates braking force to brake the vehicle according to a braking command from the control unit 130.

The control unit 130 recognizes the object information by fusing the first object information detected by the camera sensor unit 110 and the second object information detected by the radar sensor unit 120, and uses the first object information and the second object information. When the deceleration of the target object is recognized, it is determined whether the difference between the first object information and the second object information is more than a preset certain value, and if the difference is more than a certain value as a result of the determination, the sensor detected by the camera sensor unit 110 Braking control is performed based on the frame change rate of the target object.

That is, when the control unit 130 receives the first object information and the second object information from the camera sensor unit 110 and the radar sensor unit 120, the control unit 130 determines the vertical/horizontal position of the target object through the first object information, Relative speed, object type information, etc. can be checked, and the vertical/horizontal position, relative speed, acceleration, etc. of the target object can be checked through the second object information. At this time, the control unit 130 may recognize the target object as a vehicle, pedestrian, etc. based on object type information.

The control unit 130 compares the first object information and the second object information and, if the two object information is similar, recognizes the object information by fusing the first and second object information. For example, the control unit 130 may compare the positions or speeds of the preceding vehicle included in the first and second object information and determine that the first and second object information are similar if the difference does not exceed a preset certain value. . When the first and second object information are similar, the control unit 130 detects the object information by fusing the first and second object information, thereby further improving the reliability of the detected object. Here, fusion of the first and second object information may mean synchronizing the first object information and the second object information according to the time synchronization signal and detecting the target object around the vehicle using the synchronized information. .

As described above, the control unit 130 can detect highly reliable object information by fusing the first and second object information.

Meanwhile, there may be cases where the target object (leading vehicle) rapidly decelerates and decelerates beyond the speed change rate that can be determined by the radar sensor unit 120. In this case, the radar sensor unit 120 may transmit information about relative distance (position) and relative speed as incorrect values. This causes a difference in the relative distance (position) and relative speed detected by the radar sensor unit 120 and the camera sensor unit 110, resulting in the loss of fused information as shown in FIG. 2, and the risk ahead. AEB control may not be performed normally for an object. Therefore, there is a need to minimize non-operation of the automatic emergency braking device even if the fusion information is lost due to the difference between the first object information and the second object information of the radar sensor unit 120 and the camera sensor unit 110.

Accordingly, in a state where both the radar sensor unit 120 and the camera sensor unit 110 normally detect the target object until the deceleration of the target object, both the radar sensor unit 120 and the camera sensor unit 110 detect the first object of the target object. When deceleration is recognized, the control unit 130 compares the first object information and the second object information and determines whether the difference between the two object information is greater than or equal to a preset certain value. At this time, the control unit 130 may compare the relative speed and relative distance (position) of the first object information with the relative speed and relative distance (position) of the second object information to determine whether the difference is greater than a certain value. As a result of the determination, if the difference between the first object information and the second object information is more than a certain value, the control unit 130 generates the second object information from the radar sensor unit 120 due to the large deceleration of the target object (preceding vehicle). It can be judged that it is being transmitted incorrectly. If there is a difference in the relative distance (position) and relative speed detected by the radar sensor unit 120 and the camera sensor unit 110, the fusion of the first and second object information may be released.

In this way, when the fusion of the first and second object information is canceled, the control unit 130 incorrectly transmits the second object information in the case of the radar sensor unit 120 and transmits the target object (preceding object information) in the case of the camera sensor unit 110. It can be determined that the deceleration of the vehicle continues to be recognized. In this case, the control unit 130 compares the frame change rate per unit time (dF/dt) of the object detected by the camera sensor unit 110 with a preset threshold, and if it is greater than the threshold, controls the braking of the AEB system without warning the driver. Perform.

Meanwhile, the frame change rate of the target object detected by the camera sensor unit 110 may be greater than or equal to the threshold, but the distance between the target object and the own vehicle may be greater than or equal to the preset distance for each speed. In other words, the frame change rate of the target object is above the threshold, but the distance between the target object and the host vehicle is long, so the risk of collision may be low. In this case, the controller 130 may not perform braking control.

That is, when the frame change rate of the target object is greater than the threshold, the control unit 130 compares the distance between the target object and the host vehicle with a preset distance limit value for each speed, and performs braking control when the distance limit value is within the corresponding distance limit value. If it is not within this range, braking control may not be performed. At this time, the control unit 130 may have a distance limit value set for each speed as shown in FIG. 3.

For example, when the speed of the own vehicle is 50 m/s, the distance between the target object and the own vehicle is 35 m, and the frame change rate is above the threshold, braking control will be described. In this case, since the speed is 50m/s, the distance limit may be 30m. However, since the distance between the target object and the own vehicle is 35 m, the controller 130 may not perform braking control. If the speed of the own vehicle is 50 m/s and the distance between the target object and the own vehicle is 29 m, the control unit 130 can perform braking control because the distance between the target object and the own vehicle is within the distance limit.

As described above, in a state where the radar sensor unit 120 and the camera sensor unit 110 detect the object normally until the target object (preceding vehicle) decelerates, both sensor units 110 and 120 detect the target object (preceding vehicle). In a state where the first deceleration is recognized, the second object information of the radar sensor unit 120 is incorrectly transmitted, and the camera sensor unit 110 does not unconditionally perform braking control in a situation where it is recognized that the camera sensor unit 110 continues to decelerate, but the camera sensor unit 110 Braking control can be performed only when the distance between the target object recognized in (110) and the host vehicle is within a certain distance.

In this way, when the frame change rate is greater than the threshold, the control unit 130 compares the distance between the target object and the own vehicle with the preset distance limit value for each speed, and performs braking control when the comparison result is greater than the corresponding distance limit value, thereby controlling the automatic emergency braking system. Malfunctions and sensitive operations can be minimized.

Figure 4 is a flowchart for explaining a control method of an automatic emergency braking device according to an embodiment of the present invention.

Referring to FIG. 4, when the control unit 130 receives the first object information detected by the camera sensor unit 110 and the second object information detected by the radar sensor unit 120 (S410), the first object information and It is determined whether deceleration of the target object occurs from the second object information (S420).

As a result of the determination in step S420, if deceleration of the target object occurs in the first object information and the second object information, the control unit 130 determines whether the difference between the first object information and the second object information is more than a preset certain value ( S430). At this time, the control unit 130 may compare the relative distance (position) and relative speed of the first object information with the relative distance (position) and relative speed of the second object information to determine whether there is a difference of more than a certain value.

As a result of the determination in step S430, if the difference between the first object information and the second object information is more than a certain value, the control unit 130 determines whether the frame change rate of the target object detected by the camera sensor unit 110 is more than the threshold value. Do it (S440). That is, if the difference between the first object information and the second object information is more than a certain value, the control unit 130 determines that the fusion of the first and second object information is released, and the object detected by the camera sensor unit 110 It can be determined whether the frame change rate of the object is greater than or equal to the threshold.

As a result of the determination in step S440, if the frame change rate of the target object is greater than or equal to the threshold value, the control unit 130 performs automatic control (S450).

If, as a result of the determination in step S420, deceleration of the target object does not occur in the first object information and the second object information, the control unit 130 fuses the first object information and the second object information to recognize the object information (S460) ). At this time, by fusing the first and second object information, highly reliable object information can be detected.

If, as a result of the determination in step S430, the difference between the first object information and the second object information is not more than a certain value, the control unit 130 fuses the first object information and the second object information to recognize the object information (S470) ), perform step S430.

If, as a result of determination in step S440, the frame change rate of the target object is not greater than the threshold, the control unit 130 recognizes the object information by fusion of the first object information and the second object information (S470) and performs step S430. do.

Figure 5 is a flowchart for explaining a control method of an automatic emergency braking device according to another embodiment of the present invention.

Referring to FIG. 5, when the control unit 130 receives the first object information detected by the camera sensor unit 110 and the second object information detected by the radar sensor unit 120 (S510), the first object information and It is determined whether deceleration of the target object occurs from the second object information (S520).

As a result of the determination in step S520, if deceleration of the target object occurs in the first object information and the second object information, the control unit 130 determines whether the difference between the first object information and the second object information is more than a preset certain value ( S530).

As a result of the determination in step S530, if the difference between the first object information and the second object information is more than a certain value, the control unit 130 determines whether the frame change rate of the target object detected by the camera sensor unit 110 is more than the threshold value. Do it (S540).

As a result of the determination in step S540, if the frame change rate of the target object is greater than or equal to the threshold, the control unit 130 compares the distance between the target object and the host vehicle with a preset distance limit value for each speed and determines whether the distance limit is within the corresponding distance limit value (S550). .

As a result of the determination in step S550, if the distance between the target object and the own vehicle is within the corresponding distance limit value, the control unit 130 performs automatic control (S560).

If, as a result of the determination in step S520, deceleration of the target object does not occur in the first object information and the second object information, the control unit 130 fuses the first object information and the second object information to recognize the object information (S570) ).

If, as a result of the determination in step S570, the difference between the first object information and the second object information is not more than a certain value, the control unit 130 fuses the first object information and the second object information to recognize the object information (S580) ), perform step S530.

If, as a result of determination in step S540, the frame change rate of the target object is not greater than the threshold, the control unit 130 recognizes the object information by fusion of the first object information and the second object information (S580) and performs step S530. do.

As a result of the determination in step S550, if the distance between the target object and the host vehicle is not within the corresponding distance limit value, the control unit 130 fuses the first object information and the second object information to recognize the object information (S580) and performs step S530. .

As described above, the lidar sensor control device and method according to one aspect of the present invention is based on the frame change rate of the object detected by the camera sensor unit when fusion information is lost due to the information difference between the radar sensor unit and the camera sensor unit. By performing braking control, a collision with a dangerous object ahead can be prevented.

A lidar sensor control device and method according to another aspect of the present invention unconditionally performs braking control based on the frame change rate of the object detected by the camera sensor unit when fusion information is lost due to an information difference between the radar sensor unit and the camera sensor unit. Rather, by performing braking control only when the distance between the target object recognized by the camera sensor unit and the own vehicle is within a certain distance, malfunction and sensitive operation of the automatic emergency braking device can be minimized.

The present invention has been described with reference to the embodiments shown in the drawings, but these are merely exemplary, and those skilled in the art will recognize that various modifications and other equivalent embodiments are possible therefrom. You will understand.

Therefore, the true technical protection scope of the present invention should be determined by the claims below.

110: Camera sensor unit
120: Laser sensor unit
130: control unit
140: braking unit

Claims (10)

A camera sensor unit that detects first object information by capturing a front image;
A radar sensor unit that detects second object information through electromagnetic waves; and
While recognizing object information by fusing the first object information detected by the camera sensor unit and the second object information detected by the radar sensor unit, deceleration of the target object is recognized in the first object information and the second object information. Then, the difference between the first object information and the second object information is compared with a preset constant value, and if the difference is more than a certain value as a result of the comparison, braking is performed based on the frame change rate of the object detected by the camera sensor unit. Control unit that performs control
Automatic emergency braking system including.
According to paragraph 1,
The control unit,
An automatic emergency braking device characterized in that, when the difference between the first object information and the second object information is not greater than the predetermined value, the object information is recognized by fusion of the first object information and the second object information.
According to paragraph 1,
The control unit,
Comparing the frame change rate with a preset threshold, performing braking control if it is greater than the threshold, and recognizing object information by fusion of the first object information and the second object information if it is not greater than the threshold. Features automatic emergency braking system.
According to paragraph 3,
The control unit,
When the frame change rate is greater than or equal to the threshold, the distance between the target object and the own vehicle is compared with a preset distance limit value for each speed, and braking control is performed if the distance is within the corresponding distance limit value.
According to paragraph 1,
The first object information and the second object information include a relative distance and relative speed with the target object, and the target object is one or more of a preceding vehicle and a pedestrian.
A control unit receiving first object information detected by the camera sensor unit and second object information detected by the radar sensor unit;
If deceleration of the target object is recognized in the first object information and the second object information while the control unit recognizes object information by fusing the first object information and the second object information, the first object information and the second object information are recognized. 2Comparing the difference in object information with a preset constant value; and
When the difference between the first object information and the second object information is greater than a certain value, the control unit performs braking control based on the frame change rate of the target object detected by the camera sensor unit.
A control method of an automatic emergency braking system including.
According to clause 6,
In the step of performing the braking control,
The control unit compares the frame change rate with a preset threshold; and
The control unit performs braking control if the comparison result is greater than or equal to a threshold, and if the comparison result is not greater than or equal to the threshold, the control unit includes a step of recognizing object information by fusion of the first object information and the second object information. Control method of automatic emergency braking system.
In clause 7,
When performing braking control if it is above the above threshold,
The control unit compares the distance between the target object and the own vehicle with a preset distance limit value for each speed when the frame change rate is greater than the threshold value, and performs braking control if the distance is within the corresponding distance limit value. control method.
According to clause 6,
If the difference between the first object information and the second object information is not more than a certain value, the control unit recognizes the object information by fusion of the first object information and the second object information. control method.
According to clause 6,
The first object information and the second object information include a distance and relative speed with the target object, and the target object is at least one of a preceding vehicle and a pedestrian.