QP spline path and spiral path based reference line smoothing method for autonomous driving
View Patent ↗In one embodiment, a method includes the operation of segmenting a raw reference line into a plurality of reference line segments, including a first reference line segment, a second reference segment, and a third reference line segment in a sequential order, in response to receiving the raw reference line representing a route from a first location to a second location associated with an autonomous driving vehicle (ADV). The method further includes the operations of smoothing the first reference line segment and the third reference line segment using a Quadratic programming (QP) spline smoother; and smoothing the second reference line segment using a spiral smoother. Smoothed reference line segments from the plurality of reference line segments are connected to generate a smoothed reference line, which is to be used as a reference line of the route to control the ADV.
1. A computer-implemented method for operating an autonomous driving vehicle (ADV), the method comprising:
in response to receiving an initial reference line representing a route from a first location to a second location associated with an autonomous driving vehicle (ADV), segmenting, by a processor, the initial reference line into a plurality of reference line segments, including a first reference line segment, a second reference segment, and a third reference line segment in sequence;
smoothing, by the processor, the first reference line segment and the third reference line segment using a Quadratic programming (QP) spline smoothing algorithm;
smoothing, by the processor, the second reference line segment using a spiral smoothing algorithm;
connecting, by the processor, smoothed reference line segments from the plurality of reference line segments including the first reference line segment, the second reference segment, and the third reference line segment in a sequential order to generate a smoothed reference line, which is to be used as a reference line of the route to control the ADV, wherein the first reference line segment is connected to the second reference line segment, the second referenced line segment is connected to the third referenced line segment, and the second referenced line segment smoothed by using the QP spline smoothing algorithm is between the first reference line segment and the third reference line segment smoothed by using the spiral smoothing algorithm;
planning a trajectory based on the smoothed reference line; and
controlling the ADV based on the trajectory.
2. The method of claim 1 , further comprising iteratively performing smoothing using the QP spline smoothing algorithm and performing smoothing using the spiral smoothing algorithm in an alternating manner for all of the reference line segments.
3. The method of claim 1 , wherein a length of each of the plurality of reference line segments is dynamically determined based on road conditions of the route and a speed of the ADV.
4. The method of claim 1 , wherein at least one of the reference line segments is different in length from at least one other reference line segment.
5. The method of claim 1 , wherein smoothing the first reference line segment and the second reference line segment occurs during a same planning cycle.
6. The method of claim 1 , wherein smoothing the first reference line segment and the second reference line segment occurs during different planning cycles.
7. The method of claim 1 , wherein each of the first reference segment, the second reference line segment, and the third reference line segment is smoothed and optimized in a different planning cycle.
8. The method of claim 1 , wherein at least one of a set of constraints are dynamically tunable, wherein the set of constraints represent an initial location, a direction, and a curvature of the ADV.
9. A non-transitory machine-readable medium having instructions stored therein for operating an autonomous driving vehicle (ADV), the instructions, when executed by a processor, causing the processor to perform operations, the operations comprising:
in response to receiving an initial reference line representing a route from a first location to a second location associated with an autonomous driving vehicle (ADV), segmenting the initial reference line into a plurality of reference line segments, including a first reference line segment, a second reference segment, and a third reference line segment in sequence;
smoothing the first reference line segment and the third reference line segment using a Quadratic programming (QP) spline smoothing algorithm;
smoothing the second reference line segment using a spiral smoothing algorithm;
connecting smoothed reference line segments from the plurality of reference line segments including the first reference line segment, the second reference segment, and the third reference line segment in a sequential order to generate a smoothed reference line, which is to be used as a reference line of the route to control the ADV, wherein the first reference line segment is connected to the second reference line segment, the second referenced line segment is connected to the third referenced line segment, and the second referenced line segment smoothed by using the QP spline smoothing algorithm is between the first reference line segment and the third reference line segment smoothed by using the spiral smoothing algorithm;
planning a trajectory based on the smoothed reference line; and
controlling the ADV based on the trajectory.
10. The machine-readable medium of claim 9 , wherein the operations further comprise iteratively performing smoothing using the QP spline smoothing algorithm and performing smoothing using the spiral smoothing algorithm in an alternating manner for all of the reference line segments.
11. The machine-readable medium of claim 9 , wherein a length of each of the plurality of reference line segments is dynamically determined based on road conditions of the route and a speed of the ADV.
12. The machine-readable medium of claim 9 , wherein at least one of the reference line segments is different in length from at least one other reference line segment.
13. The machine-readable medium of claim 9 , wherein smoothing the first reference line segment and the second reference line segment occurs during a same planning cycle.
14. The machine-readable medium of claim 9 , wherein smoothing the first reference line segment and the second reference line segment occurs during different planning cycles.
15. The machine-readable medium of claim 9 , wherein each of the first reference segment, the second reference line segment, and the third reference line segment is smoothed and optimized in a different planning cycle.
16. The machine-readable medium of claim 9 , wherein at least one of a set of constraints are dynamically tunable, wherein the set of constraints represent an initial location, a direction, and a curvature of the ADV.
17. A data processing system, comprising:
a processor; and
a memory coupled to the processor to store instructions, which when executed by the processor, cause the processor to perform operations, the operations including
in response to receiving an initial reference line representing a route from a first location to a second location associated with an autonomous driving vehicle (ADV), segmenting the initial reference line into a plurality of reference line segments, including a first reference line segment, a second reference segment, and a third reference line segment in sequence,
smoothing the first reference line segment and the third reference line segment using a Quadratic programming (QP) spline smoothing algorithm,
smoothing the second reference line segment using a spiral smoothing algorithm,
connecting smoothed reference line segments from the plurality of reference line segments including the first reference line segment, the second reference segment, and the third reference line segment in a sequential order to generate a smoothed reference line, which is to be used as a reference line of the route to control the ADV, wherein the first reference line segment is connected to the second reference line segment, the second referenced line segment is connected to the third referenced line segment, and the second referenced line segment smoothed by using the QP spline smoothing algorithm is between the first reference line segment and the third reference line segment smoothed by using the spiral smoothing algorithm;
planning a trajectory based on the smoothed reference line; and
controlling the ADV based on the trajectory.
18. The system of claim 17 , wherein the operations further comprise iteratively performing smoothing using the QP spline smoothing algorithm and performing smoothing using the spiral smoothing algorithm in an alternating manner for all of the reference line segments.
19. The system of claim 17 , wherein a length of each of the plurality of reference line segments is dynamically determined based on road conditions of the route and a speed of the ADV.
20. The system of claim 17 , wherein at least one of the reference line segments is different in length from at least one other reference line segment.