Method of detecting road-curb with LiDAR sensor and road-curb detecting apparatus for performing the method

1 . A method of detecting a road-curb that is performed by a road-curb detecting system of a vehicle, the method comprising:

obtaining points around the vehicle using a lidar sensor of the road-curb detecting system by emitting a laser beam in a predetermined direction and receiving a reflected laser beam from an object reflecting the laser beam;

generating a circular grid map and dividing the circular grid map by a predetermined unit distance and a predetermined unit angle to form a plurality of cells;

arranging the points received from the lidar sensor in the plurality of cells;

detecting the road-curb based on the points arranged in the plurality of cells; and

upon the detecting of the road-curb, providing a processing technique suitable for a real-time operation of a control system of the vehicle through rapid data processing,

wherein the detecting of the road-curb includes:

determining, among the plurality of cells, a first cell in which a difference in heights between points is within a first predetermined range as a road-curb candidate cell;

determining a road-curb cell based on a second cell and a third cell, each of which has a value of an angular component on the circular grid map that is equal to an angular component of the first cell, and

providing road-curb information corresponding to the determined road-curb cell to an autonomous driving system of the vehicle,

wherein the autonomous driving system controls a movement of the vehicle based on the road-curb information such that the vehicle is prevented from traveling toward a non-road area separated from a road area by the determined road-curb cell,

wherein the determining of the road-curb cell includes:

selecting a cell having a value of a radius component on the circular grid map that is smaller than a value of a radius component of the first cell as the second cell;

selecting another cell having a value of a radius component on the circular grid map that is greater than the value of the radius component of the first cell as the third cell; and

determining the first cell as the road-curb cell if a height difference between a point having a height lower than any other cells in the second cell and a point having a height lower than any other cells in the third cell is within a second predetermined range.

2 . The method of claim 1 , wherein the second cell and the third cell are adjacent to the first cell.

3 . The method of claim 1 , wherein a distance between the second cell and the third cell is shorter than or equal to a predetermined distance.

4 . The method of claim 1 , wherein the detecting of the road-curb further includes determining, as road-curb candidate points, points respectively having heights within a third predetermined range among points arranged in the road-curb cell.

5 . The method of claim 4 , wherein the detecting of the road-curb further includes:

performing a first line fitting process using the road-curb candidate points, and

detecting a first road-curb using first points that are inlier points obtained in the first line fitting process if a number of the first points is greater than or equal to a predetermined value.

6 . The method of claim 5 , wherein the detecting of the road-curb further includes:

performing a second line fitting process using second points remaining after removing the first points from among the road-curb candidate points, and

detecting a second road-curb using third points that are inlier points obtained in the second line fitting process if a number of the third points is greater than or equal to the predetermined value.

7 . A non-transitory computer-readable storage medium including computer-executable instructions which cause, when executed by a processor, the processor to perform a method of detecting a road-curb that is performed by a road-curb detecting system of a vehicle, the method including:

obtaining points around the vehicle using a lidar sensor of the road-curb detecting system by emitting a laser beam in a predetermined direction and receiving a reflected laser beam from an object reflecting the laser beam;

generating a circular grid map and dividing the circular grid map by a predetermined unit distance and a predetermined unit angle to form a plurality of cells;

arranging the points received from the lidar sensor in the plurality of cells;

detecting the road-curb based on the points arranged in the plurality of cells;

upon the detecting of the road-curb, providing a processing technique suitable for a real-time operation of a control system of the vehicle through rapid data processing,

wherein the detecting of the road-curb includes:

determining, among the plurality of cells, a first cell in which a difference in heights between points is within a first predetermined range as a road-curb candidate cell;

determining a road-curb cell based on a second cell and a third cell, each of which has a value of an angular component on the circular grid map that is equal to an angular component of the first cell, and

providing road-curb information corresponding to the determined road-curb cell to an autonomous driving system of the vehicle,

wherein the autonomous driving system controls a movement of the vehicle based on the road-curb information such that the vehicle is prevented from traveling toward a non-road area separated from a road area by the determined road-curb cell,

wherein the determining of the road-curb cell includes:

selecting a cell having a value of a radius component on the circular grid map that is smaller than a value of a radius component of the first cell as the second cell;

selecting another cell having a value of a radius component on the circular grid map that is greater than the value of the radius component of the first cell as the third cell; and

determining the first cell as the road-curb cell if a height difference between a point having the smallest height in the second cell and a point having the smallest height in the third cell is within a second predetermined range.

8 . The non-transitory computer-readable storage medium of claim 7 , wherein the second cell and the third cell are adjacent to the first cell.

9 . The non-transitory computer-readable storage medium of claim 7 , wherein a distance between the second cell and the third cell is shorter than or equal to a predetermined distance.

10 . The non-transitory computer-readable storage medium of claim 7 , wherein the detecting of the road-curb further includes determining, as road-curb candidate points, points respectively having heights within a third predetermined range among points arranged in the road-curb cell.

11 . The non-transitory computer-readable storage medium of claim 10 , wherein the detecting of the road-curb further includes:

performing a first line fitting process using the road-curb candidate points, and

detecting a first road-curb using first points that are inlier points obtained in the first line fitting process if a number of the first points is greater than or equal to a predetermined value.

12 . The non-transitory computer-readable storage medium of claim 11 , wherein the detecting of the road-curb further includes:

performing a second line fitting process using second points remaining after removing the first points from among the road-curb candidate points, and

detecting a second road-curb using third points that are inlier points obtained in the second line fitting process if a number of the third points is greater than or equal to the predetermined value.

13 . A road-curb detecting system of a vehicle, the system comprising:

a lidar sensor of the vehicle for obtaining points around the vehicle; and

a road-curb detecting apparatus communicatively coupled with the lidar sensor which emits a laser beam in a predetermined direction and receives a reflected laser beam from an object reflecting the laser beam and the road-curb detecting apparatus for generating a circular grid map and dividing the circular grid map by a predetermined unit distance and a predetermined unit angle to form a plurality of cells and for arranging the points received from the lidar sensor in the plurality of cells, for detecting a road-curb based on the points arranged in the plurality of cells, and, upon the detecting of the road-curb, for providing a processing technique suitable for a real-time operation of a control system of the vehicle through rapid data processing,

wherein the detecting of the road-curb includes:

determining, among the plurality of cells, a first cell in which a difference in heights between points is within a first predetermined range as a road-curb candidate cell;

determining a road-curb cell based on a second cell and a third cell, each of which has a value of an angular component on the circular grid map that is equal to an angular component of the first cell, and

providing road-curb information corresponding to the determined road-curb cell to an autonomous driving system of the vehicle,

wherein the autonomous driving system controls a movement of the vehicle based on the road-curb information such that the vehicle is prevented from traveling toward a non-road area separated from a road area by the determined road-curb cell,

wherein the determining of the road-curb cell includes:

selecting a cell having a value of a radius component on the circular grid map that is smaller than a value of a radius component of the first cell as the second cell;

selecting another cell having a value of a radius component on the circular grid map that is greater than the value of the radius component of the first cell as the third cell; and

determining the first cell as the road-curb cell if a height difference between a point having the smallest height in the second cell and a point having the smallest height in the third cell is within a second predetermined range.

14 . The road-curb detecting system of claim 13 , wherein, in the detecting of the road-curb, the road-curb detecting apparatus further determines, as road-curb candidate points, points respectively having heights within a third predetermined range among points arranged in the road-curb cell.