Bulldozer planning and control
Systems and methods of bulldozer planning and control are disclosed.
1 . A computer-implemented method of controlling an earth-moving vehicle (EMV) including a blade, the method comprising:
(a) directing, by one or more computers, the EMV in a target region having a portion of soil to remove, wherein the blade is not touching the ground;
(b) detecting, by the one or more computers, one or more changes in a terrain of the target region;
(c) generating, by the one or more computers, a terrain map based at least in part on the one or more changes in the terrain;
(d) determining, by the one or more computers, a path for the EMV to traverse based at least in part on the terrain map;
(e) calculating, by the one or more computers, a target depth based at least in part on a target volume of soil, wherein the target volume of soil is equal to a product of the target depth, a width of the blade, and a target distance of cutting, and wherein the target distance of cutting includes a cut distance, a cut start point, and a cut end point for the EMV; and
(f) dynamically adjusting, by the one or more computers, a depth of the blade as the EMV traverses the path to obtain the target volume of soil, wherein traversing the path comprises moving the EMV from the cut start point and the cut end point for a dry run.
2 . The method of claim 1 , wherein the terrain map includes a plurality of features comprising one or more elevations, angles, slopes, distances, and/or soils.
3 . The method of claim 2 , wherein detecting one or more changes comprises using a sensor to detect the plurality of features.
4 . The method of claim 3 , wherein the sensor comprises a light detection and ranging (LIDAR) detector mounted on the EMV.
5 . The method of claim 4 , wherein the sensor uses kinematics modeling to detect one or more blind spots of the LIDAR detector, and wherein the kinematics modeling comprises one or more of computations of angle, speed, terrain perception, or blade position.
6 . The method of claim 3 , wherein the sensor includes an inertial measurement unit (IMU).
7 . The method of claim 2 , wherein the terrain map is three-dimensional (3D).
8 . The method of claim 1 , wherein generating the terrain map comprises generating a piecewise linear function of the target region.
9 . The method of claim 8 , wherein the piecewise linear function includes a two-dimensional (2D) representation of the target region, and wherein the 2D representation corresponds to an x-direction and a z-direction of the terrain.
10 . The method of claim 9 , wherein the x-direction represents a lateral movement from a cut start point to a cut end point, and wherein the z-direction represents a vertical movement from the cut start point to the cut end point.
11 . The method of claim 10 , wherein the piecewise linear function includes one or more angles between a plurality of slopes of the terrain.
12 . The method of claim 8 , wherein generating the terrain map comprises approximating one or more features of the terrain, wherein the piecewise linear function comprises a plurality of linear pieces that are connected to one another, and wherein approximating the one or more features comprises setting a length of the pieces to a predetermined length.
13 . The method of claim 1 , wherein traversing the path comprises moving the EMV from the cut end point to the cut start point after the dry run, wherein determining the path comprises determining the target depth of the blade at each of a plurality of points between the cut start point and the cut end point.
14 . The method of claim 1 , wherein traversing the path comprises moving the EMV along one or more elevations and/or one or more slopes of the target region.
15 . The method of claim 1 , further comprising:
(a) determining, by the one or more computers, that a volume of soil in the blade is at capacity before the EMV has traversed the path;
(b) directing, by the one or more computers, the EMV to raise its blade above the ground at break point; and
(c) directing, by the one or more computers, the EMV away from the path to remove the soil from the blade.
16 . The method of claim 15 , further comprising:
(a) directing, by the one or more computers, the EMV back to move to the break point after removing the soil from the blade;
(b) determining, by the one or more computers, a remainder of the path for the EMV to traverse to remove the soil; and
(c) directing, by the one or more computers, the EMV to resume dynamic adjustment of the depth of the blade until a cut point is reached.
17 . A computer-implemented method of controlling an earth-moving vehicle (EMV) including a blade, the method comprising:
(a) directing, by one or more computers, the EMV in a target region having a portion of soil to remove, wherein the blade is not touching the ground;
(b) detecting, by the one or more computers, one or more changes in a terrain of the target region;
(c) generating, by the one or more computers, a terrain map based at least in part on the one or more changes in the terrain, wherein generating the terrain map comprises generating a piecewise linear function of the target region, wherein the piecewise linear function includes a two-dimensional (2D) representation of the target region, and wherein the 2D representation corresponds to an x-direction and a z-direction of the terrain;
(d) determining, by the one or more computers, a path for the EMV to traverse based at least in part on the terrain map; and
(e) dynamically adjusting, by the one or more computers, a depth of the blade as the EMV traverses the path to obtain the target volume of soil.
18 . A computer-implemented method of controlling an earth-moving vehicle (EMV) including a blade, the method comprising:
(a) directing, by one or more computers, the EMV in a target region having a portion of soil to remove, wherein the blade is not touching the ground;
(b) detecting, by the one or more computers, one or more changes in a terrain of the target region;
(c) generating, by the one or more computers, a terrain map based at least in part on the one or more changes in the terrain, wherein generating the terrain map comprises generating a piecewise linear function of the target region, wherein generating the terrain map comprises approximating one or more features of the terrain, wherein the piecewise linear function comprises a plurality of linear pieces that are connected to one another, and wherein approximating the one or more features comprises setting a length of the pieces to a predetermined length;
(d) determining, by the one or more computers, a path for the EMV to traverse based at least in part on the terrain map; and
(e) dynamically adjusting, by the one or more computers, a depth of the blade as the EMV traverses the path to obtain the target volume of soil.