Systems and methods for determining buffer regions

1 . A system comprising:

one or more processors; and

one or more non-transitory computer-readable media storing instructions executable by the one or more processors, wherein the instructions, when executed, cause the system to perform operations comprising:

receiving a trajectory associated with a vehicle in an environment;

determining a predicted region of travel for a front bumper of the vehicle based at least in part on the trajectory and a width of the vehicle, the predicted region of travel being along a drivable surface in the environment;

determining a set of points along the trajectory;

determining, based on the set of points, a set of line segments, a line segment of the set of line segments having a width equal to the width of the vehicle, being normal to the trajectory, and passing through a point of the set of points;

determining a plurality of polygons associated with the predicted region of travel, a polygon of the plurality of polygons defined by two sequential line segments of the set of line segments and four lines extending normal to the two sequential line segments, each line of the four lines passing through a different terminal node of the two sequential line segments;

determining an intermediate polygon based at least in part on a union of the plurality of polygons;

determining a convex polygonal buffer region encompassing the intermediate polygon; and

controlling the vehicle based at least in part on the convex polygonal buffer region.

2 . The system of claim 1 , wherein determining the polygon of the plurality of polygons comprises determining an intersection point between a first line of the four lines associated with a first line segment of the two sequential line segments and a second line of the four lines associated with a second line segment of the two sequential line segments.

3 . The system of claim 2 , wherein determining the polygon is further based at least in part on a direction of a vehicle turn associated with the first line segment of the two sequential set of line segments.

4 . The system of claim 1 , wherein determining the convex polygonal buffer region comprises removing a concave vertex from the intermediate polygon.

5 . The system of claim 1 , wherein controlling the vehicle comprises performing one or more maneuvering operations to avoid an object detected within the convex polygonal buffer region.

6 . One or more non-transitory computer-readable media storing instructions that, when executed by one or more processors, perform operations comprising:

determining a predicted region of travel for a vehicle based at least in part on a vehicle trajectory, the predicted region of travel being along a drivable surface in an environment;

determining, based on a set of points along the vehicle trajectory, a set of line segments, a line segment of the set of line segments having a width equal to a width of the vehicle, being normal to the vehicle trajectory, and passing through a point of the set of points;

determining a plurality of polygons associated with the predicted region of travel, a polygon of the plurality of polygons defined by two sequential line segments of the set of line segments and four lines extending normal to the two sequential line segments, each line of the four lines passing through a different terminal node of the two sequential line segments;

determining a convex polygonal buffer region encompassing the predicted region of travel based at least in part on the plurality of polygons;

outputting a signal comprising the convex polygonal buffer region; and

controlling the vehicle based at least in part on the convex polygonal buffer region.

7 . The one or more non-transitory computer-readable media of claim 6 , wherein the line segment of the set of line segments is associated with a stopping point.

8 . The one or more non-transitory computer-readable media of claim 6 , wherein determining the plurality of polygons comprises:

determining that the polygon of the plurality of polygons is not substantially rectangular; and

determining, based at least in part on determining that the polygon is not substantially rectangular, a vertex of the polygon based at least in part on an intersection point of two subsequent tangent lines associated with the predicted region of travel.

9 . The one or more non-transitory computer-readable media of claim 8 , wherein determining the polygon is further based at least in part on a direction of a vehicle turn.

10 . The one or more non-transitory computer-readable media of claim 6 , wherein determining the convex polygonal buffer region comprises:

combining the plurality of polygons into a combined polygon;

removing a first vertex of the combined polygon associated with first outside edges of the combined polygon that extend outwards from the predicted region of travel; and

retaining a second vertex of the combined polygon associated with second outside edges of the combined polygon that extend inwards towards the predicted region of travel.

11 . The one or more non-transitory computer-readable media of claim 6 , wherein individual line segments of the set of line segments are substantially equal length segments of a longitudinal center length along the predicted region of travel.

12 . The one or more non-transitory computer-readable media of claim 6 , wherein the operations further comprise detecting an object in the environment based at least in part on the convex polygonal buffer region.

13 . The one or more non-transitory computer-readable media of claim 12 , wherein the operations further comprise:

determining an intermediate polygon based at least in part on a union of the plurality of polygons; and

based at least in part on detecting the object based at least in part on the convex polygonal buffer region, detecting the object based at least in part on the intermediate polygon.

14 . A method comprising:

determining a predicted region of travel for a vehicle based at least in part on a vehicle trajectory, the predicted region of travel being along a drivable surface in an environment;

determining, based on a set of points along the vehicle trajectory, a set of line segments, a line segment of the set of line segments having a width equal to a width of the vehicle, being normal to the vehicle trajectory, and passing through a point of the set of points;

determining a plurality of polygons associated with the predicted region of travel, a polygon of the plurality of polygons defined by two sequential line segments of the set of line segments and four lines extending normal to the two sequential line segments, each line of the four lines passing through a different terminal node of the two sequential line segments;

determining a convex polygonal buffer region encompassing the predicted region of travel based at least in part on the plurality of polygons; and

controlling the vehicle based at least in part on the convex polygonal buffer region.

15 . The method of claim 14 , wherein controlling the vehicle comprises initiating a vehicle stopping operation based at least in part on detecting an obstacle within the convex polygonal buffer region.

16 . The method of claim 14 , wherein controlling the vehicle comprises initiating a vehicle stopping operation before the vehicle enters the convex polygonal buffer region.

17 . The method of claim 14 , wherein determining the plurality of polygons comprises determining a predicted vehicle position based at least in part on a predicted position of one or more data points associated with a component of the vehicle.

18 . The method of claim 14 , wherein determining the plurality of polygons is further based at least in part on one or more intersections of one or more tangent vectors associated with a predicted vehicle position.

19 . The method of claim 18 , wherein determining the plurality of polygons is further based at least in part on whether the one or more tangent vectors extend inwards towards the predicted region of travel.