APPARATUS FOR TRACKING OBJECT BASED ON LIDAR SENSOR AND METHOD THEREFOR

An apparatus for tracking an object based on a LiDAR sensor and a method therefor are provided. The apparatus includes a LiDAR sensor that generates point cloud data around an autonomous vehicle and a controller that detects objects based on the point cloud data and selects valid objects among the detected objects as targets to be tracked.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit of priority to Korean Patent Application No. 10-2020-0030373, filed on Mar. 11, 2020, the entire contents of which are incorporated herein by reference.

TECHNICAL FIELD

The present disclosure relates to technologies of selecting objects (valid objects) affecting an autonomous vehicle among objects detected based on a light detection and ranging (LiDAR) sensor as targets to be tracked.

BACKGROUND

In general, a point cloud refers to a set of data on a coordinate system, which is defined as x, y, and z coordinates on a three-dimensional (3D) coordinate system and mostly indicates an external surface of an object. Such a point cloud may be generated by a 3D light detection and ranging (LiDAR) sensor. The 3D LiDAR sensor is loaded into an autonomous vehicle and is mainly used to detect vehicles and lines around the autonomous vehicle and various obstacles.

Since the 3D LiDAR sensor generates a substantial amount of point clouds in an area around the autonomous vehicle, an efficient clustering technology is required. For example, a technology of clustering point clouds projects a point cloud (a 3D point) onto a square grid map in a two-dimensional (2D) form to be converted into a 2D point and uses an “8-neighborhood” technique for the converted 2D point on the square grid map.

Meanwhile, since most object tracking devices have a processing limit on hardware performance, the number of objects capable of being tracked is limited. When the number of objects detected based on a LiDAR sensor is greater than a reference number, a conventional object tracking device first selects reference numbers of the first detected objects as targets to be tracked based on a scan order of the LiDAR sensor. Additionally, since such a conventional object tracking device selects objects to be tracked based on only a scan order of the LiDAR sensor without regard to a situation where an autonomous vehicle is traveling, an object (e.g., a road boundary, an object around the autonomous vehicle, or the like) affecting the driving of the autonomous vehicle is excluded from targets to be tracked.

Details described in the background art are written to increase the understanding of the background of the present disclosure, which may include details rather than an existing technology well known to those skilled in the art.

SUMMARY

The present disclosure has been made to solve the above-mentioned problems occurring in the prior art while advantages achieved by the prior art are maintained intact. An aspect of the present disclosure provides an apparatus for tracking an object based on a LiDAR sensor to improve driving safety of an autonomous vehicle by detecting objects based on the LiDAR sensor loaded into the autonomous vehicle and selecting objects affecting the driving of the autonomous vehicle among the detected objects as targets to be tracked to track valid objects in a situation where the autonomous vehicle is traveling and a method therefor.

According to an aspect of the present disclosure, an apparatus for tracking an object based on a LiDAR sensor may include a LiDAR sensor configured to generate point cloud data around an autonomous vehicle and a controller configured to detect objects based on the point cloud data and selects valid objects among the detected objects as targets to be tracked. In an exemplary embodiment of the present disclosure, the controller may be configured to sequentially exclude objects, each of which has low effectiveness, among the detected objects to select reference numbers of valid objects, based on a reference table corresponding to a situation where the autonomous vehicle is traveling.

In addition, the controller may be configured to select the reference numbers of valid objects based on a first reference table corresponding to a straight road, when a road where the autonomous vehicle is traveling is the straight road. In addition, the controller may be configured to determine the road where the autonomous vehicle is traveling as the straight road, when a speed of the autonomous vehicle is greater than a reference speed and when a curvature of the road is greater than a first reference curvature. The controller may be configured to determine the road where the autonomous vehicle is traveling as the straight road, when a speed of the autonomous vehicle is less than or equal to a reference speed and when a steering angle of the autonomous vehicle is less than or equal to a reference steering angle.

Further, the controller may be configured to select the reference numbers of valid objects based on a second reference table corresponding to a first curved road, when a road where the autonomous vehicle is traveling is the first curved road. In addition, the controller may be configured to determine the road where the autonomous vehicle is traveling as the first curved road, when a speed of the autonomous vehicle is greater than a reference speed and when a curvature of the road is less than or equal to a first reference curvature and is greater than a second reference curvature. The controller may be configured to select the reference numbers of valid objects based on a third reference table corresponding to a second curved road, when a road where the autonomous vehicle is traveling is the second curved road.

In an exemplary embodiment of the present disclosure, the controller may be configured to determine the road where the autonomous vehicle is traveling as the second curved road, when a speed of the autonomous vehicle is greater than a reference speed and when a curvature of the road is less than or equal to a second reference curvature. The controller may be configured to select the reference numbers of valid objects based on a fourth reference table, when a speed of the autonomous vehicle is less than or equal to a reference speed and when a steering angle of the autonomous vehicle is greater than a reference steering angle.

According to another aspect of the present disclosure, a method for tracking an object based on a LiDAR sensor may include generating, by the LiDAR sensor, point cloud data around an autonomous vehicle and detecting, by a controller, objects based on the point cloud data and selecting, by the controller, valid objects among the detected objects as targets to be tracked. In addition, the selecting of the valid objects as the targets to be tracked may include sequentially excluding objects, each of which has low effectiveness, among the detected objects to select reference numbers of valid objects, based on a reference table corresponding to a situation where the autonomous vehicle is traveling.

The selecting of the reference numbers of valid objects may include selecting the reference numbers of valid objects based on a first reference table corresponding to a straight road, when a road where the autonomous vehicle is traveling is the straight road. In an exemplary embodiment of the present disclosure, the selecting of the reference numbers of valid objects may further include determining the road where the autonomous vehicle is traveling as the straight road, when a speed of the autonomous vehicle is greater than a reference speed and when a curvature of the road is greater than a first reference curvature.

The selecting of the reference numbers of valid objects may further include determining the road where the autonomous vehicle is traveling as the straight road, when a speed of the autonomous vehicle is less than or equal to a reference speed and when a steering angle of the autonomous vehicle is less than or equal to a reference steering angle. Additionally, the selecting of the reference numbers of valid objects may include selecting the reference numbers of valid objects based on a second reference table corresponding to a first curved road, when a road where the autonomous vehicle is traveling is the first curved road.

In an exemplary embodiment of the present disclosure, the selecting of the reference numbers of valid objects may include determining the road where the autonomous vehicle is traveling as the first curved road, when a speed of the autonomous vehicle is greater than a reference speed and when a curvature of the road is less than or equal to a first reference curvature and is greater than a second reference curvature. The selecting of the reference numbers of valid objects may include selecting the reference numbers of valid objects based on a third reference table corresponding to a second curved road, when a road where the autonomous vehicle is traveling is the second curved road.

Further, the selecting of the reference numbers of valid objects may include determining the road where the autonomous vehicle is traveling as the second curved road, when a speed of the autonomous vehicle is greater than a reference speed and when a curvature of the road is less than or equal to a second reference curvature. The selecting of the reference numbers of valid objects may include selecting the reference numbers of valid objects based on a fourth reference table, when a speed of the autonomous vehicle is less than or equal to a reference speed and when a steering angle of the autonomous vehicle is greater than a reference steering angle.

DETAILED DESCRIPTION

FIG. 1is a block diagram illustrating a configuration of an apparatus for tracking an object based on a LiDAR sensor according to an exemplary embodiment of the present disclosure. As shown inFIG. 1, an apparatus100for tracking an object based on a LiDAR sensor according to an exemplary embodiment of the present disclosure may include a storage10, a LiDAR sensor20, and a controller30. In particular, the respective components may be combined into one component and some components may be omitted, based on a manner which executes the apparatus100for tracking the object based on the LiDAR sensor according to an exemplary embodiment of the present disclosure.

Seeing the respective components, first of all, the storage10may be configured to store various logics, algorithms, and programs required in a process of detecting objects based on the LiDAR sensor20loaded into an autonomous vehicle and selecting objects (valid objects) affecting the driving of the autonomous vehicle among the detected objects as targets to be tracked. The storage10may be configured to store a reference steering angle (e.g., 20 degrees) or a reference curvature used to determine a shape of the road. In particular, the reference curvature may include a first reference curvature (e.g., 250 m/rad) and a second reference curvature (e.g., 100 m/rad).

The storage10may be configured to store a first reference table used to select a valid object on a straight road. Such a first reference table may include a plurality of step fields for sequentially removing objects, each of which has low effectiveness. For example, the first reference table applied to a straight road shown inFIG. 2is Table 1 below. In particular, a higher priority may be assigned to a line close based on an autonomous vehicle210in a ranking for each line.

TABLE 1Step 1Medium Object in fifth rankingStep 2Medium Object 40 meters away in lateraldirection, in fourth rankingStep 3Rear Small Object in fourth rankingStep 4Small Object in fourth rankingStep 5Small Object in three rankingStep 6Medium Object in three rankingStep 7Small Object in second rankingStep 8All Objects in fifth, fourth, or third rankingStep 9All Object in second rankingStep 10Small Object in first rankingStep 11All Object in first ranking

Herein, ‘Step 1’ indicates an object first excluded in selecting a valid object (e.g., an object with the lowest effectiveness), and ‘Step 11’ indicates an object last excluded in selecting a valid object (e.g., an object with the highest effectiveness). In particular, when the number of detected objects is less than or equal to a reference number, all the detected objects may be selected as valid objects. When the number of the detected objects is greater than the reference number, the detected objects may be sequentially excluded from ‘Step 1’.

Furthermore, ‘Small Object’ in the fourth ranking refers to an object, a length of which is less than about 4 m and a width of which is less than about 4 m ‘Small Object’ in the third ranking refers to an object, a length of which is less than about 2 m and a width of which is less than about 2 m. ‘Small Object’ in the first or second ranking refers to an object, a length of which is less than about 1 m and a width of which is less than about 1 m. Furthermore, ‘Medium Object’ is an object except for a stopped object such as a road boundary, which refers to an object, a length of which is less than about 8 m and a width of which is less than about 8 m.

The storage10may be configured to store a second reference table used to select a valid object on a gentle curved road. For example, as shown inFIG. 3, the second reference table applied to a gentle curved road is Table 2 below.

TABLE 2Step 1Medium Object in fifth rankingStep 2Medium Object 40 meters away in lateraldirection, in fourth rankingStep 3Rear Small Object in fourth rankingStep 4Small Object in fourth rankingStep 5Small Object on outer curved road, in third rankingStep 6Medium Object in fourth rankingMedium Object on outer curved road, in thirdrankingStep 7Small Object on inner curved road, in third rankingSmall Object in second rankingStep 8All Objects in fifth or fourth rankingAll Object on outer curved road, in third rankingStep 9All Objects on inner curved road, in third rankingAll Objects in second rankingStep 10Small Object in first rankingStep 11All Objects in first ranking

The storage10may store a third reference table used to select a valid object on a sharp curved road. For example, as shown inFIG. 4, the third reference table applied to a sharp curved road is Table 3 below.

TABLE 3Step 1Medium Object in fifth rankingStep 2Medium Object 40 meters away in lateraldirection, in fourth rankingStep 3Rear Small Object in fourth rankingStep 4Small Object in fourth rankingStep 5All Objects in fourth or fifth rankingStep 6Small Object on outer curved road, in third rankingStep 7Small Object on inner curved road, in third rankingStep 8All Objects on outer curved road, in third rankingStep 9Small Object in second or first rankingStep 10All Objects on inner curved road, in third rankingStep 11All Objects in second or first rankings

While the autonomous vehicle slows down (e.g., at a speed of about 20 kph or less) and when a steering angle is greater than a reference steering angle (e.g., about 20 degrees), the storage10may be configured to store a fourth reference table used to select a valid object. For example, as shown inFIG. 5, the fourth reference table applied while the autonomous vehicle210slows down on the road is Table 4 below.

TABLE 4Step 1Medium Object in fifth rankingStep 2Medium Object 40 meters away in lateraldirection, in fourth rankingStep 3Rear Small Object in fourth rankingStep 4Small Object in fourth rankingStep 5Medium Object in fourth rankingStep 6All Objects in fifth or fourth rankingsStep 7Small Object in third rankingStep 8Medium Object in third rankingStep 9All Objects in third rankingStep 10Small Object in second or first rankingsStep 11All Objects in second or first ranking

The storage10may include at least one type of storage medium, such as a flash memory type memory, a hard disk type memory, a micro type memory, a card type memory (e.g., a secure digital (SD) card or an extreme digital (XD) card), a random access memory (RAM), a static RAM (SRAM), a read-only memory (ROM), a programmable ROM (PROM), an electrically erasable PROM (EEPROM), a magnetic RAM (MRAM), a magnetic disk, and an optical disk.

The LiDAR sensor20may be loaded into the autonomous vehicle to generate point cloud data for objects around the autonomous vehicle. The controller30may be configured to perform overall control such that respective components may normally perform their own functions. Such a controller30may be implemented in the form of hardware, may be implemented in the form of software, or may be implemented in the form of a combination thereof. Preferably, the controller30may be implemented as, but not limited to, a microprocessor.

Particularly, the controller30may be configured to perform a variety of control in a process of detecting objects based on the LiDAR sensor20loaded into the autonomous vehicle and selecting objects (valid objects) affecting the driving of the autonomous vehicle among the detected objects as targets to be tracked. The controller30may include an information collecting device31, an object detector32, and a valid object selecting device33as functional blocks. Hereinafter, the operation of the controller30will be described in detail based on each functional block.

The information collecting device31may have a communication interface with a vehicle network200and may be configured to collect a variety of information over the vehicle network200. For example, the information collecting device31may be configured to collect steering angle information, vehicle speed information, yaw rate information, turn signal information (turn signal ON information), or the like over the vehicle network200. In particular, the vehicle network200may include a controller area network (CAN), a local interconnect network (LIN), FlexRay, media oriented systems transport (MOST), an Ethernet, or the like. The information collecting device31may interwork with a navigation device300provided in the autonomous vehicle to collect destination path information.

The object detector32may be configured to detect objects based on the point cloud data obtained through the LiDAR sensor20. In particular, since the detection of the object is well known and commonly used and is not the gist of the present disclosure, a detailed description thereof will be omitted. The valid object selecting device33may be configured to select a valid object among the objects detected by the object detector32, based on the plurality of reference tables stored in the storage10and the information collected by the information collecting device31. In other words, the valid object selecting device33may be configured to specify one of the plurality of reference tables based on the information collected by the information collecting device31and select a valid object based on the specified reference table.

Hereinafter, the operation of the valid object selecting device33will be described with reference toFIGS. 2 to 6.FIG. 2is a drawing illustrating a process of selecting a valid object on a straight road in a valid object selecting device provided in an apparatus for tracking an object based on a LiDAR sensor according to an exemplary embodiment of the present disclosure.

First of all, when the vehicle speed collected by an information collecting device31ofFIG. 1is greater than a reference speed (e.g., about 20 kph) and when a curvature of the road where an autonomous vehicle210is traveling is greater than a first reference curvature (e.g., about 250 m/rad), a valid object selecting device33ofFIG. 1may be configured to determine the road where the autonomous vehicle210is traveling as a straight road. In particular, the valid object selecting device33may be configured to calculate curvature based on the vehicle speed and the yaw rate collected by the information collecting device31. Since the detailed manner to calculate the curvature is well known and commonly used, a description thereof will be omitted.

Furthermore, when the vehicle speed collected by the information collecting device31is less than or equal to the reference speed (e.g., about 20 kph) and when a steering angle of the autonomous vehicle210is less than or equal to a reference steering angle (e.g., about 20 degrees), the valid object selecting device33may be configured to determine the road where the autonomous vehicle210is traveling as a straight road. In response to determining that the road where the autonomous vehicle210is traveling is the straight road, the valid object selecting device33may be configured to select a valid object based on a first reference table stored in a storage10ofFIG. 1.

When the number of objects detected by an object detector32ofFIG. 1is less than or equal to a reference number (e.g., about 50), the valid object selecting device33may be configured to select all the detected objects as valid objects. When the number of the detected objects is greater than the reference number, the valid object selecting device33may be configured to sequentially exclude objects from objects corresponding to ‘Step 1’ to objects corresponding to ‘Step 11’ to select reference numbers of valid objects.

FIG. 3is a drawing illustrating a process of selecting a valid object on a gentle curved road in a valid object selecting device provided in an apparatus for tracking an object based on a LiDAR sensor according to an exemplary embodiment of the present disclosure. First of all, when the vehicle speed collected by an information collecting device31ofFIG. 1is greater than a reference speed (e.g., about 20 kph) and when curvature calculated based on the vehicle speed and the yaw rate collected by the information collecting device31is less than or equal to a first reference curvature (e.g., about 250 m/rad) and is greater than a second reference curvature (e.g., about 100 m/rad), a valid object selecting device33ofFIG. 1may be configured to determine the road where an autonomous vehicle210is traveling as a gentle curved road.

In response to determining that the road where the autonomous vehicle210is traveling is the gentle curved road, the valid object selecting device33may be configured to select a valid object based on a second reference table stored in a storage10ofFIG. 1. When the number of objects detected by an object detector32ofFIG. 1is less than or equal to a reference number (e.g., about 50), the valid object selecting device33may be configured to select all the detected objects as valid objects. In response to determining that the number of the detected objects is greater than the reference number, the valid object selecting device33may be configured to sequentially exclude objects from ‘Step 1’ to select reference numbers of valid objects.

FIG. 4is a drawing illustrating a process of selecting a valid object on a sharp curved road in a valid object selecting device provided in an apparatus for tracking an object based on a LiDAR sensor according to an exemplary embodiment of the present disclosure. First of all, when the vehicle speed collected by an information collecting device31ofFIG. 1is greater than a reference speed (e.g., about 20 kph) and when curvature calculated based on the vehicle speed and the yaw rate collected by the information collecting device31is less than or equal to a second reference curvature (e.g., about 100 m/rad), a valid object selecting device33ofFIG. 1may be configured to determine the road where an autonomous vehicle210is traveling as a sharp curved road.

In response to determining that the road where the autonomous vehicle210is traveling is the sharp curved road, the valid object selecting device33may be configured to select a valid object based on a third reference table stored in a storage10ofFIG. 1. When the number of objects detected by an object detector32ofFIG. 1is less than or equal to a reference number (e.g., about 50), the valid object selecting device33may be configured to select all the detected objects as valid objects. When the number of the detected objects is greater than the reference number, the valid object selecting device33may be configured to sequentially exclude objects from ‘Step 1’ to select reference numbers of valid objects. InFIG. 4, a fifth ranking refers to a front outer area and a rear outer area of the curved road (e.g., a first ranking, a second ranking, and a third ranking).

FIG. 5is a drawing illustrating a process of selecting a valid object upon steering while an autonomous vehicle slows down in a valid object selecting device provided in an apparatus for tracking an object based on a LiDAR sensor according to an exemplary embodiment of the present disclosure. First of all, when the vehicle speed collected by an information collecting device31ofFIG. 1is less than or equal to a reference speed (e.g., about 20 kph) and when a steering angle of an autonomous vehicle210is greater than a reference steering angle (e.g., about 20 degrees), a valid object selecting device33ofFIG. 1may be configured to determine that the autonomous vehicle210is being steered while slowing down.

In response to determining that the autonomous vehicle210is being steered while slowing down, the valid object selecting device33may be configured to select a valid object based on a fourth reference table stored in a storage10ofFIG. 1. When the number of objects detected by an object detector32ofFIG. 1is less than or equal to a reference number (e.g., about 50), the valid object selecting device33may be configured to select all the detected objects as valid objects. When the number of the detected objects is greater than the reference number, the valid object selecting device33may be configured to sequentially exclude objects from ‘Step 1’ to select reference numbers of valid objects.

FIG. 6is a drawing illustrating a ranking assigned for each line upon a lane change in a valid object selecting device provided in an apparatus for tracking an object based on a LiDAR sensor according to an exemplary embodiment of the present disclosure. First of all, a valid object selecting device33ofFIG. 1may be configured to determine an intention of a driver to perform a lane change based on turn signal information and steering angle information collected by an information collecting device31ofFIG. 1. Furthermore, the valid object selecting device33may be configured to determine an intention of an autonomous vehicle210to perform a lane change based on navigation path information collected by the information collecting device31.

When the intention of the driver to perform a lane change or the intention of the autonomous vehicle210to perform a lane change is determined, the valid object selecting device33may be configured to change a ranking assigned for each line. As shown inFIG. 6, when the autonomous vehicle210attempts to enter an exit ramp610from the road where it is traveling, the valid object selecting device33may be configured to change a ranking for each line. In other words, the valid object selecting device33may be configured to set the exit ramp610to a first ranking, set the periphery of the exit ramp620to a second ranking, and set the line where the autonomous vehicle21is currently traveling to a third ranking.

Thereafter, the valid object selecting device33may be configured to select reference numbers of valid objects among objects detected by an object detector32ofFIG. 1as targets to be tracked based on a reference table corresponding to a shape of the exit ramp610. InFIG. 6, a second ranking refers to a two-sided area of the exit ramp610.

FIGS. 7A-7Bare drawings illustrating reference numbers of valid objects selected on a straight road by an apparatus for tracking an object based on a LiDAR sensor according to an exemplary embodiment of the present disclosure. InFIGS. 7A-7B, objects displayed in a dotted line (rectangular dotted lines) indicate objects detected by an object detector32ofFIG. 1, and objects displayed in a solid line (rectangular solid lines) indicate valid objects selected by a valid object selecting device33ofFIG. 1.

Since an existing method selects reference numbers of valid objects as targets to be tracked based on a scan order of a LiDAR sensor20ofFIG. 1without regard to a situation where an autonomous vehicle210is traveling, as shown in reference numeral710, it may be seen that valid objects (e.g., a vehicle, a guardrail, and the like) are excluded from the targets to be tracked. Additionally, since a method according to an exemplary embodiment of the present disclosure selects reference numbers of valid objects as targets to be tracked with regard to a situation where the autonomous vehicle210is traveling (e.g., a shape of the road, an intention to perform a lane change, whether the autonomous vehicle201slows down, or the like), as shown in reference numeral720, it may be seen that valid objects (e.g., a vehicle, a guardrail, and the like) are included in the targets to be tracked.

FIGS. 8A-8Bare drawings illustrating reference numbers of valid objects selected on a gentle curved road by an apparatus for tracking an object based on a LiDAR sensor according to an embodiment of the present disclosure. InFIGS. 8A-8B, objects displayed in a dotted line (rectangular dotted lines) indicate objects detected by an object detector32ofFIG. 1, and objects displayed in a solid line (rectangular solid lines) indicate valid objects selected by a valid object selecting device33ofFIG. 1.

Since an existing method selects reference numbers of valid objects as targets to be tracked based on a scan order of a LiDAR sensor20ofFIG. 1without regard to a situation where an autonomous vehicle210is traveling, as shown in reference numeral810, it may be seen that valid objects (e.g., a vehicle, a guardrail, and the like) are excluded from the targets to be tracked. Additionally, since a method according to an exemplary embodiment of the present disclosure selects reference numbers of valid objects as targets to be tracked with regard to a situation where the autonomous vehicle210is traveling (e.g., a shape of the road, an intention to perform a lane change, whether the autonomous vehicle201slows down, or the like), as shown in reference numeral820, it may be seen that valid objects (e.g., a vehicle, a guardrail, and the like) are included in the targets to be tracked.

FIGS. 9A-9Bare drawings illustrating reference numbers of valid objects selected on a sharp curved road by an apparatus for tracking an object based on a LiDAR sensor according to an exemplary embodiment of the present disclosure. InFIGS. 9A-9B, objects displayed in a dotted line (rectangular dotted lines) indicate objects detected by an object detector20ofFIG. 1, and objects displayed in a solid line (rectangular solid lines) indicate valid objects selected by a valid object selecting device33ofFIG. 1.

Since an existing method selects reference numbers of valid objects as targets to be tracked based on a scan order of a LiDAR sensor20ofFIG. 1without regard to a situation where an autonomous vehicle210is traveling, as shown in reference numeral910, it may be seen that valid objects (e.g., a vehicle, a guardrail, and the like) are excluded from the targets to be tracked. Additionally, since a method according to an exemplary embodiment of the present disclosure selects reference numbers of valid objects as targets to be tracked with regard to a situation where the autonomous vehicle210is traveling (e.g., a shape of the road, an intention to perform a lane change, whether the autonomous vehicle201slows down, or the like), as shown in reference numeral920, it may be seen that valid objects (e.g., a vehicle, a guardrail, and the like) are included in the targets to be tracked.

FIGS. 10A-10Bare drawings illustrating reference numbers of valid objects selected upon steering while a vehicle slows down by an apparatus for tracking an object based on a LiDAR sensor according to an exemplary embodiment of the present disclosure. InFIG. 10, objects displayed in a dotted line (rectangular dotted lines) indicate objects detected by an object detector20ofFIG. 1, and objects displayed in a solid line (rectangular solid lines) indicate valid objects selected by a valid object selecting device33ofFIG. 1.

Since an existing method selects reference numbers of valid objects as targets to be tracked based on a scan order of a LiDAR sensor20ofFIG. 1without regard to a situation where an autonomous vehicle210is traveling, as shown in reference numeral1010, it may be seen that valid objects (e.g., a vehicle, a guardrail, and the like) are excluded from the targets to be tracked. Additionally, since a method according to an additionally embodiment of the present disclosure selects reference numbers of valid objects as targets to be tracked with regard to a situation where the autonomous vehicle210is traveling (e.g., a shape of the road, an intention to perform a lane change, whether the autonomous vehicle201slows down, or the like), as shown in reference numeral1020, it may be seen that valid objects (e.g., a vehicle, a guardrail, and the like) are included in the targets to be tracked.

FIG. 11is a flowchart illustrating a method for tracking an object based on a LiDAR sensor according to an exemplary embodiment of the present disclosure. First of all, in operation1101, a LiDAR sensor20ofFIG. 1may be configured to generate point cloud data around an autonomous vehicle. In operation1102, a controller30ofFIG. 1may be configured to cluster the point cloud data generated by the LiDAR sensor20. In operation1103, the controller30may be configured to generate a contour with respect to the clustered point cloud. In operation1104, the controller30may be configured to detect one contour as one object.

Herein, operation1102, operation1103, and operation1104are collectively referred to as an object detection process. Such an object detection process is not the gist of the present disclosure and is fine to use any well-known and commonly-used technology. In operation1105, the controller30may be configured to determine whether the number of the detected objects is greater than a reference number (e.g., 50).

In response to determining that the number of the detected objects is less than or equal to the reference number (e.g., 50) as a result of the determination in operation1105, in operation1106, the controller30may be configured to select all the detected objects as valid objects. In response to determining that the number of the detected objects is greater than the reference number as a result of the determination in operation1105, in operation1107, the controller30may be configured to sequentially exclude objects from objects, each of which has low effectiveness, to select reference numbers of valid objects. In particular, the manner where the controller30selects the reference numbers of valid objects is as follows:

1) When the road where the autonomous vehicle is traveling is a straight road, the controller30may be configured to select the reference numbers of valid objects based on a first reference table corresponding to the straight road.
2) When the road where the autonomous vehicle is traveling is a first curved road, the controller30may be configured to select the reference numbers of valid objects based on a second reference table corresponding to the first curved road.
3) When the road where the autonomous vehicle is traveling is a second curved road, the controller30may be configured to select the reference numbers of valid objects based on a third reference table corresponding to the second curved road.
4) When the speed of the autonomous vehicle is less than or equal to a reference speed and when the steering angle of the autonomous vehicle is greater than a reference steering angle, the controller30may be configured to select the reference numbers of valid objects based on a fourth reference table.

In operation1108, the controller30may be configured to select the reference numbers of valid objects as targets to be tracked.

FIG. 12is a block diagram illustrating a computing system for executing a method for tracking an object based on a LiDAR sensor according to an exemplary embodiment of the present disclosure. Referring toFIG. 12, the method for tracking the object based on the LiDAR sensor according to an exemplary embodiment of the present disclosure may be implemented by the computing system. A computing system1000may include at least one processor1100, a memory1300, a user interface input device1400, a user interface output device1500, storage1600, and a network interface1700, which are connected with each other via a bus1200.

Thus, the operations of the method or the algorithm described in connection with the embodiments disclosed herein may be embodied directly in hardware or a software module executed by the processor1100, or in a combination thereof. The software module may reside on a storage medium (that is, the memory1300and/or the storage1600) such as a RAM, a flash memory, a ROM, an EPROM, an EEPROM, a register, a hard disk, a removable disk, and a CD-ROM. The exemplary storage medium may be coupled to the processor1100, and the processor1100may read information out of the storage medium and may record information in the storage medium. Alternatively, the storage medium may be integrated with the processor1100. The processor and the storage medium may reside in an application specific integrated circuit (ASIC). The ASIC may reside within a user terminal. In another case, the processor and the storage medium may reside in the user terminal as separate components.

The apparatus for tracking the object based on the LiDAR sensor and the method therefor may improve driving safety of an autonomous vehicle by detecting objects based on the LiDAR sensor loaded into the autonomous vehicle and selecting objects affecting the driving of the autonomous vehicle among the detected objects as targets to be tracked to track valid objects in a situation where the autonomous vehicle is traveling.