METHOD OF AND APPARATUS FOR CONTROLLING VEHICLE TRAVELING ON BRANCH ROAD

Method of controlling a vehicle on a branch road, including determining whether a vehicle is traveling on a last lane of a road, monitoring movement in a lateral direction of a preceding vehicle, determining whether a curvature difference between a left lane and a right lane for the vehicle meets a threshold, determining whether an amount of movement in the lateral direction of the preceding vehicle is smaller than a reference movement, in response to the curvature difference between the left vehicle lane and the right vehicle lane meeting the threshold, and correcting vehicle lane information associated with an exit road side of the last lane using vehicle lane information associated with an opposite side of the last lane where the exit road is connected to the road, in response to the amount of movement in the lateral direction of the preceding vehicle being smaller than the reference movement.

CROSS REFERENCE TO RELATED APPLICATION

The present application claims the benefit under 35 USC § 119(a) of Korean Patent Application No. 10-2020-0167505, filed Dec. 3, 2020, in the Korean Intellectual Property Office, the entire disclosure of which is incorporated herein by reference for all purposes.

BACKGROUND OF THE INVENTION

Field

The following description relates to a technology for a vehicle to keep traveling on a vehicle lane.

Description of Related Art

In recent years, there has been an ever-increasing trend to employ Advanced Driver Assistance Systems (ADAS) or autonomous traveling technologies. Among these technologies, a technology for automatically keeping traveling on a vehicle lane is one of fundamental and important technologies.

Due to the presence of an exit road branching off from a main road, when keeping traveling on a vehicle lane, a vehicle currently traveling on the last vehicle lane of the main road experiences confusion in a reference for vehicle-lane keeping control. Thus, control stability of the vehicle is decreased during traveling on a branch road.

SUMMARY OF THE INVENTION

In one general aspect, there is provided a processor-implemented method of controlling a vehicle traveling on a branch road, the method including determining whether a vehicle is traveling on a last lane of a main road, monitoring an amount of movement in a lateral direction of a preceding vehicle, in response to the vehicle traveling on the last lane, determining whether a curvature difference between a left vehicle lane and a right vehicle lane for the vehicle meets a threshold, determining whether the amount of movement in the lateral direction of the preceding vehicle is smaller than a reference movement, in response to the curvature difference between the left vehicle lane and the right vehicle lane meeting the threshold, and correcting vehicle lane information associated with an exit road side of the last lane using vehicle lane information associated with a side of the last lane opposite to a side where the exit road is connected to the main road, in response to the amount of movement in the lateral direction of the preceding vehicle being smaller than the reference movement.

The determining of whether the vehicle is traveling on the last lane of the main road may include determining that the vehicle is traveling on the last lane, in response to detecting that the last lane and a road border are located on the side of the main road where the exit road is connected to the main road and only a vehicle lane is detected opposite to the side where the exit road is connected to the main road.

The determining of whether the amount of movement in the lateral direction of the preceding vehicle is smaller than the reference movement may include determining the amount of movement in the lateral direction of the preceding vehicle is smaller than the reference movement based on a comparison of the amount of movement in the lateral direction of the preceding vehicle travelling through a position at which the curvature difference between the left vehicle lane and the right vehicle lane is at or above the threshold with the reference movement.

The determining of whether the amount of movement in the lateral direction of the preceding vehicle is smaller than the reference movement may include determining the amount of movement in the lateral direction of the preceding vehicle is smaller than the reference movement based on setting the reference movement is to a positive number, setting an amount of movement by which the preceding vehicle moves in a direction of the exit road to be a positive number, setting an amount of movement by which the preceding vehicle moves in a direction away from the exit road to be a negative number, and comparing these amounts of movement with the reference movement.

The method may include determining whether vehicle lane information associated with the side where the exit road is connected to the main road and information on a vehicle road border are similar to each other, in response to the amount of movement in the lateral direction of the preceding vehicle being equal to or larger than the reference movement, wherein correcting the vehicle lane information associated with the exit road side using the vehicle lane information associated with the side opposite to the side where the exit road is connected to the main road, in response to determining that the vehicle lane information associated with the side where the exit road is connected with the main road and the information on the vehicle road border are similar to each other.

In another general aspect, there is provided an apparatus for controlling a vehicle traveling on a branch road, the apparatus including forward-viewing imaging sensor configured to detect lanes adjacent to both sides of a road on which the vehicle travels and a preceding vehicle, a vehicle lane determiner configured to determining whether the vehicle is traveling on the last lane of the road, using a signal of the forward-view imaging sensor, a monitor configured to monitor an amount of movement in a lateral direction of the preceding vehicle, using the signal of the forward-view imaging sensor, a curvature determiner configured to determine whether a curvature difference between a left vehicle lane and a right vehicle lane meets a threshold, using the signal of the forward-view imaging sensor, an amount-of-movement determiner configured to determining whether the amount of movement in the lateral direction of the preceding vehicle is smaller than a reference movement, in response to the curvature difference between the left vehicle lane and the right vehicle lane meeting the threshold, and a vehicle lane corrector configured to correct vehicle lane information associated with an exit road side of the last lane using vehicle lane information associated with a side of the last lane opposite to a side where the exit road is connected to the road, in response to the amount of movement in the lateral direction of the preceding vehicle being smaller than the reference movement.

The vehicle lane determiner may be configured to determine that the vehicle is traveling on the last vehicle lane of the road, in response to determining that the last lane and a road border are located on the side of the road where the exit road is connected to the road and only a vehicle lane is detected opposite to the side where the exit road is connected to the road.

The amount-of-movement determiner may be configured to compare the amount of movement in the lateral direction of the preceding vehicle travelling through a position at which the curvature difference between the left vehicle lane and the right vehicle lane is at or above the threshold, with the reference movement.

The amount-of-movement determiner may be configured to set the reference movement to a positive number, to set an amount of movement by which the preceding vehicle moves in a direction of the exit road to be a positive number, to set an amount of movement by which the preceding vehicle moves in a direction away from the exit road to be a negative number, and to compare these amounts of movement with the reference movement.

The vehicle lane determiner may be configured to determine whether or vehicle lane information associated with the side where the exit road is connected to the road and information on a vehicle road border are similar to each other, in response to the amount of movement in the lateral direction of the preceding vehicle being equal to or larger than the reference movement, and the vehicle lane corrector may be configured to correct the vehicle lane information associated with the exit road side using the vehicle lane information associated with the side opposite to the side where the exit road is connected to the road, in response to determining that the vehicle lane information associated with the side where the exit road is connected with the road and the information on the vehicle road border are similar to each other.

The apparatus may include a vehicle-lane-keeping controller configured to maintain the vehicle on the vehicle lane on which the vehicle is currently traveling, by controlling a vehicle steering apparatus using the vehicle lane information corrected by the vehicle lane corrector.

DETAILED DESCRIPTION OF THE INVENTION

Also, in the description of the components, terms such as first, second, A, B, (a), (b) or the like may be used herein when describing components of the present disclosure. These terms are used only for the purpose of discriminating one constituent element from another constituent element, and the nature, the sequences, or the orders of the constituent elements are not limited by the terms. When one constituent element is described as being “connected”, “coupled”, or “attached” to another constituent element, it should be understood that one constituent element can be connected or attached directly to another constituent element, and an intervening constituent element can also be “connected”, “coupled”, or “attached” to the constituent elements.

When describing the examples with reference to the accompanying drawings, like reference numerals refer to like constituent elements and a repeated description related thereto will be omitted. In the description of examples, detailed description of well-known related structures or functions will be omitted when it is deemed that such description will cause ambiguous interpretation of the present disclosure.

Desired embodiments of the present invention will be described in detail below with reference to the accompanying drawings. The same reference character on the drawings refers to the same constituent element.

With reference toFIGS. 1 to 3, a method of controlling a vehicle traveling on a branch road according to an embodiment of the present invention is configured to include Step S10of determining whether or not a vehicle V is traveling on the last vehicle lane of a main road; Step S20of monitoring an amount of movement in a lateral direction of a preceding vehicle FV; Step S30of determining whether or not a curvature difference between a left vehicle lane LL and a right vehicle lane RL for the vehicle V is at or above a predetermined reference value (may also be referred to as “threshold”); Step S40of determining whether or not the amount of movement in the lateral direction of the preceding vehicle FV is smaller than a predetermined reference amount of movement (may also be referred to as “reference movement”), when the curvature difference between the left vehicle lane LL and the right vehicle lane RL is at or above the predetermined reference value; and Step S50of correcting vehicle lane information associated with the exit road ER side using vehicle lane information associated with the other side opposite to one side where the exit road ER is connected, when the amount of movement in the lateral direction of the preceding vehicle FV is smaller than the predetermined reference amount of movement.

That is, according to the present invention, in a case where the vehicle V is traveling on the last vehicle lane of the main road from which the exit road ER branches off, because the curvature difference between the left vehicle lane LL and the right vehicle lane RL is at or above the predetermined reference value, when it is determined that there is a high likelihood that the last vehicle lane will be a portion to which the exit road ER is connected, the amount of movement in the lateral direction of the preceding vehicle FV is compared with the predetermined reference amount of movement. As a result of the comparison, in a case where it is determined that the preceding vehicle travels straight without any lane change instead of traveling in the exit road ER side, the vehicle lane information associated with the exit road ER side is quickly corrected without any additional checking, and thus the vehicle V is enabled to keep traveling on a vehicle lane, using the vehicle lane information corrected as described above. Accordingly, vehicle steering control is performed in a stable and smooth manner without causing a shake. Consequently, the vehicle V is enabled to pass in a stable state along the portion of the main road MR to which the exit road ER is connected.

The main road MR here means a two-or-more lane vehicle road on which the vehicle V in which the present invention finds application travels. The last vehicle lane here means, as an outermost lane of the main road MR, a vehicle lane which is the most adjacent to the exit road ER and from which the exit road ER substantially branches off.

In Step S10of determining whether or not the vehicle V is traveling on the last vehicle lane of the main road MR, in a case where a vehicle lane and a vehicle road border W are together detected on the one side where the exit road ER is connected to a vehicle road on which the vehicle V is traveling and where only the vehicle lane is detected on the other side opposite to the one side, it may be determined that the vehicle V is traveling on the last vehicle lane of the main road MR.

The vehicle road border W here means all objects that can indicate a road border area other than a vehicle lane, such as a curbstone physically protruding from a surface of a vehicle road, a guard rail, and a vehicle road wall.

That is, in a case where the vehicle V is traveling on the last vehicle lane of the main road MR, it is normal that only a vehicle lane may be detected on one side and that the vehicle lane and the vehicle road border W may be detected together on the other side, that is, on the side where the exit road ER is connected. With the detection of this difference, it is determined that the vehicle V is traveling on the last vehicle lane.

Of course, in a case where identification of the vehicle road on which the vehicle V is traveling is possible with a large-scale map and a navigation device, and a high-precision global positioning system (GPS), the technology, as described above, that is embodied in the present invention may be together used. Thus, a situation where the vehicle V is traveling on the last vehicle lane may be recognized with a high degree of reliability.

In Step S20of monitoring the amount of movement in the lateral direction of the preceding vehicle FV, necessary data are generated and stored in such a manner that an amount of movement by which the preceding vehicle FV moves in the lateral direction with respect to a traveling direction of the vehicle V for an interval between arbitrary two points in time at a certain position on a vehicle road will be verified at a later point in time.

Step S30of determining whether or not the curvature difference between the left vehicle lane LL and the right vehicle lane RL for the vehicle V is at or above the predetermined reference value is performed in order to determine whether or not the vehicle V substantially starts to pass along the portion to which the exit road ER is connected.

That is, when the vehicle V travels a portion to which the exit road ER is not connected, the respective curvature of the left vehicle lane LL and the right vehicle lane RL for the vehicle V have a range of values approximately similar to each other. However, when the portion to which the exit road ER is connected is approached, a great difference occurs between respective curvatures of vehicle lanes adjacent to both sides, respectively, of the vehicle V. With identification of this difference, it is primarily determined whether or not the vehicle V currently starts to travel on the portion from which the exit road ER branches off.

Therefore, for the purpose as described above, through many experiments and analyses at the design stage, the predetermined reference value may be determined as a value on the basis of which the portion from which the exit road ER branches off is identified.

In Step S40of determining whether or not the amount of movement in the lateral direction of the preceding vehicle FV is smaller than the predetermined reference amount of movement, the amount of movement in the lateral direction that is obtained while the preceding vehicle FV travels through a position at which the curvature difference between the left vehicle lane LL and the right vehicle lane RL is at or above the predetermined reference value is compared with the predetermined reference amount of movement.

That is, because the curvature difference between the left and right vehicle lanes is at or above the predetermined reference value, once when there is a high likelihood that a vehicle lane will be a portion from which an exit vehicle lane branches off, the amount of movement in the lateral direction that is obtained while the preceding vehicle FV travels on this portion is compared with the predetermined reference amount of movement.

At this point, the predetermined reference amount of movement is set to a positive number. Furthermore, as illustrated inFIG. 3, an amount of movement by which the preceding vehicle FV moves in the direction of the exit road ER is set to be expressed as a positive number, and an amount of movement by which the preceding vehicle FV moves in the opposite direction is set to be expressed as a negative number. These amounts of movement are compared with the predetermined reference amount of movement.

Therefore, if the amount of movement in the lateral direction that is obtained while the preceding vehicle FV travels is smaller than the predetermined reference amount of movement, it may be determined not only that the preceding vehicle FV does not move toward the exit road ER side, but also that the preceding vehicle FV travels straight without any lane change on a vehicle road on which the preceding vehicle FV currently travels. Therefore, according to the present invention, it may be ensured that it is safe for the vehicle V to travel straight without any lane change, following the preceding vehicle FV. Accordingly, as described above, the vehicle lane information associated with the exit road ER side is corrected using the vehicle lane information associated with the other side opposite to the one side where the exit road ER is connected. Then, vehicle-lane keeping control is continuously performed using the corrected vehicle lane information. Thus, suitable and stable control for enabling the vehicle V to keep traveling on a vehicle lane is performed. Accordingly, the safety and reliability of the vehicle V can be improved.

For reference, inFIG. 2, it is illustrated that, in a situation where the exit road ER branches off in the rightward direction from the main road MR, the right vehicle lane RL is corrected with the determination as described above using information on the left vehicle lane LL and that a corrected vehicle lane NL is generated.

Therefore, as described above, it is desirable that the predetermined reference amount of movement is set to a level on the basis of which a situation where the preceding vehicle FV travels from the main road MR through the exit road ER and a situation where, otherwise, the preceding vehicle FV continues traveling straight on a vehicle lane on which the preceding vehicle FV currently travels are distinguished from each other. The predetermined reference amount of movement may also be determined through many experiments and analyses at the design stage.

In a case where the amount of movement in the lateral direction of the preceding vehicle FV is equal to or larger than the predetermined reference amount of movement, Step S60of determining whether or not vehicle lane information associated with the one side where the exit road ER is connected and information on the vehicle road border W are similar to each other is further performed. In a case where it is determined that the vehicle lane information associated with the exit road ER side is connected and the information on the vehicle road border W are similar to each other, Step S50of correcting the vehicle lane information associated with the exit road ER side using the vehicle lane information associated with the other side opposite to the one side where the exit road ER is connected may be set to be performed.

That is, when the amount of movement in the lateral direction of the preceding vehicle FV is equal to or larger than the predetermined reference amount of movement, there is a high likelihood that the preceding vehicle FV will travel toward the exit road ER side. However, the main road MR itself may be curved in the direction in which the exit road ER is expected to appear. Therefore, as described above, it is determined whether or not the vehicle lane information associated with the one side where the exit road ER is connected and the information on the vehicle road border W are similar to each other, and then a situation where the exit road ER is actually connected is verified. Thereafter, in order that the vehicle V in which the present invention finds application continues traveling straight, the vehicle lane is corrected as described above, and thus the vehicle V is enabled to keep traveling on a vehicle lane using the corrected vehicle lane.

With reference toFIG. 4, an apparatus for controlling a vehicle to traveling on a branch road is configured to include a forward-view imaging sensor1provided in such a manner to detect vehicle lanes adjacent to both sides, respectively, of a vehicle road on which a vehicle V travels and a preceding vehicle FV; a vehicle lane determination unit3(may also be referred to as vehicle lane determiner3) determining whether or not the vehicle V is traveling on the last vehicle lane of a main road MR, using a signal of the forward-view imaging sensor1; a monitoring unit5(may also be referred to as monitor5) monitoring an amount of movement in a lateral direction of the preceding vehicle FV, using the signal of the forward-view imaging sensor1; a curvature determination unit7(may also be referred to as curvature determiner7) determining whether or nota curvature difference between a left vehicle lane LL and a right vehicle lane RL for the vehicle V is at or above a predetermined reference value, using the signal of the forward-view imaging sensor1; an amount-of-movement determination unit9(may also be referred to as amount-of-movement determiner9) determining whether or not the amount of movement in the lateral direction of the preceding vehicle FV observed by the monitoring unit5is smaller than a predetermined reference amount of movement, when the curvature difference between the left vehicle lane LL and the right vehicle lane RL is at or above the predetermined reference value; and a vehicle lane correction unit11(may also be referred to as vehicle lane corrector11) correcting vehicle lane information associated with the exit road ER side using vehicle lane information associated with the other side opposite to one side where the exit road ER determined by the vehicle lane determination unit3is connected, in a case where the amount of movement in the lateral direction of the preceding vehicle FV is smaller than the predetermined reference amount of movement.

The forward-view imaging sensor1may be configured as a forward-view camera or the like. A single forward-view camera may be provided. A plurality of forward-view cameras may be provided in such a manner that the monitoring of the preceding vehicle FV is performed with a separate forward-view camera.

The vehicle lane determination unit3may be configured in such a manner as to determine that the vehicle V is traveling on the last vehicle lane of the main road MR in a case where a vehicle lane and a vehicle road border W are together detected on one side where the exit road ER is connected to a vehicle road on which the vehicle V is traveling and where only the vehicle lane is detected on the other side opposite to the one side.

The amount-of-movement determination unit9may be configured in such a manner as to compare the amount of movement in the lateral direction, which is obtained while the preceding vehicle FV travels through a position at which the curvature difference between the left vehicle lane LL and the right vehicle lane RL is at or above the predetermined reference value, with the predetermined reference amount of movement.

The amount-of-movement determination unit9may be configured in such a manner that the predetermined reference amount of movement is set to a positive number, that the amount of movement by which the preceding vehicle FV moves in a direction of the exit road ER is set to be expressed as a positive number, that the amount of movement by which the preceding vehicle FV moves in the opposite direction is set to be expressed as a negative number, and that these amounts of movement are compared with the predetermined reference amount of movement.

The vehicle lane determination unit3may be configured in such a manner that, in the case where the amount of movement in the lateral direction of the preceding vehicle FV is equal to or larger than the predetermined reference amount of movement, it is determined whether or not vehicle lane information associated with the one side where the exit road ER is connected and information on the vehicle road border W are similar to each other. Furthermore, the vehicle lane correction unit11may be configured in such a manner that, in the case where it is determined that the vehicle lane information associated with the one side where the exit road ER is connected and the information on the vehicle road border W are similar to each other, the vehicle lane information associated with the exit road ER side is corrected using the vehicle lane information associated with the other side opposite to the one side where the exit road ER is connected.

In addition, the apparatus for controlling a vehicle traveling on a branch road may be configured to further include a vehicle-lane-keeping controller15that enables the vehicle V to keep traveling on the vehicle lane by controlling a vehicle steering apparatus13using the vehicle lane information corrected by the vehicle lane correction unit11.

An objective of the present invention is to provide a method of controlling a vehicle traveling on a branch road and an apparatus for controlling a vehicle traveling on a branch road, the method and the apparatus being capable of performing suitable and stable vehicle-lane keeping control, thereby preventing confusion that, due to an exit road branching off from a main road, may be caused when a vehicle currently traveling on the last vehicle lane of the main road performs vehicle-lane keeping control. With the apparatus and the method, the stability and reliability of the vehicle can be improved, and thus the marketability thereof can be improved.

The instructions or software to control a processor or computer to implement the hardware components and perform the methods as described above, and any associated data, data files, and data structures, are recorded, stored, or fixed in or on one or more non-transitory computer-readable storage media. Examples of a non-transitory computer-readable storage medium include read-only memory (ROM), random-access programmable read only memory (PROM), electrically erasable programmable read-only memory (EEPROM), random-access memory (RAM), magnetic RAM (MRAM), spin-transfer torque(STT)-MRAM, static random-access memory (SRAM), thyristor RAM (T-RAM), zero capacitor RAM (Z-RAM), twin transistor RAM (TTRAM), conductive bridging RAM(CBRAM), ferroelectric RAM (FeRAM), phase change RAM (PRAM), resistive RAM(RRAM), nanotube RRAM, polymer RAM (PoRAM), nano floating gate Memory(NFGM), holographic memory, molecular electronic memory device), insulator resistance change memory, dynamic random access memory (DRAM), static random access memory (SRAM), flash memory, non-volatile memory, CD-ROMs, CD-Rs, CD+Rs, CD-RWs, CD+RWs, DVD-ROMs, DVD-Rs, DVD+Rs, DVD-RWs, DVD+RWs, DVD-RAMs, BD-ROMs, BD-Rs, BD-R LTHs, BD-REs, blue-ray or optical disk storage, hard disk drive (HDD), solid state drive (SSD), flash memory, a card type memory such as multimedia card micro or a card (for example, secure digital (SD) or extreme digital (XD)), magnetic tapes, floppy disks, magneto-optical data storage devices, optical data storage devices, hard disks, solid-state disks, and any other device that is configured to store the instructions or software and any associated data, data files, and data structures in a non-transitory manner and providing the instructions or software and any associated data, data files, and data structures to a processor or computer so that the processor or computer can execute the instructions. In an example, the instructions or software and any associated data, data files, and data structures are distributed over network-coupled computer systems so that the instructions and software and any associated data, data files, and data structures are stored, accessed, and executed in a distributed fashion by the one or more processors or computers.