Autonomous Control Of Powered Earth-Moving Vehicles To Control Slope-Based Stopping Operations

Abstract

Systems and techniques are described for implementing autonomous control of powered earth-moving vehicles, including to automatically control movement of some or all of a powered earth-moving vehicle on a job site to manage vehicle motion based in part on the determined slope of surrounding surfaces. For example, the automated operations may include initiating a stop to vehicle motion (or alternatively, a change in a planned vehicle path) if a planned travel path of the vehicle is determined to have one or more slopes in one or more sections that exceed one or more defined thresholds or otherwise having one or more determined attributes that satisfy one or more criteria.

What is claimed is: 
     
         1 . An autonomous vehicle controlled stopping system, comprising:
 a powered earth-moving vehicle having a chassis, at least one of tracks or wheels, at least one of a brake pedal or a decelerator pedal, one or more LiDAR (light detection and ranging) components mounted on the powered earth-moving vehicle, controls for manipulating movement of the at least one of the tracks or wheels via the at least one of the brake pedal or the decelerator pedal, and piston displacement mechanisms capable of effecting movement of the controls;   a microcontroller unit on the powered earth-moving vehicle that is capable of effecting movement of the controls via the piston displacement mechanisms; and   a control system on the powered earth-moving vehicle that is configured to communicate with the microcontroller unit and to perform automated operations including at least:
 obtaining LiDAR data from the one or more LiDAR components for one or more areas in a planned travel path of the powered earth-moving vehicle on a job site, the LiDAR data including a point cloud having a plurality of 3D (three-dimensional) data points on surfaces in the planned travel path; 
 determining, for each of one or more sections of terrain in the one or more areas in the planned travel path and based at least in part on a subset of the 3D data points in that section, a slope of the terrain in that section; 
 determining, while the powered earth-moving vehicle is in motion along the planned travel path and based at least in part on the determined slope for at least one of the sections of terrain being above a defined slope threshold, to initiate controlled stopping of the powered earth-moving vehicle before the powered earth-moving vehicle travels over the at least one section; and 
 activating, in response to the determining to initiate the controlled stopping, the at least one of the brake pedal or the decelerator pedal using one or more of the controls via one or more of the piston displacement mechanisms until one or more criteria related to motion of the powered earth-moving vehicle are satisfied. 
   
     
     
         2 . The autonomous vehicle controlled stopping system of  claim 1  wherein the activating of the at least one of the brake pedal or the decelerator pedal includes applying one or more defined amounts of force to the at least one of the brake pedal or the decelerator pedal via the one or more piston displacement mechanisms, wherein the one or more criteria related to the motion of the powered earth-moving vehicle include a speed of the powered earth-moving vehicle being below a defined speed threshold, wherein the powered earth-moving vehicle further has one or more tool attachments rotatably coupled to the chassis via one or more hydraulic arms, and wherein the automated operations further include:
 lowering, after the one or more criteria related to the motion of the powered earth-moving vehicle are satisfied and via at least one of the piston displacement mechanisms, at least one of the tool attachments to be in contact with the terrain; and 
 after the lowering of the at least one of the tool attachments, activating a parking brake of the powered earth-moving vehicle. 
 
     
     
         3 . The autonomous vehicle controlled stopping system of  claim 1  wherein the automated operations include dividing the one or more areas of the planned travel path into a grid having a plurality of cells, wherein each of the one or more sections of terrain include at least one of the cells, and wherein the automated operations further include determining that the slope of the terrain for the at least one section is above the defined slope threshold includes:
 determining that the subset of the 3D data points in the at least one section are above a defined minimum quantity threshold; and 
 determining that a difference in height between a lowest of the 3D data points of that subset and a highest of the 3D data points of that subset is above a defined height difference threshold. 
 
     
     
         4 . The autonomous vehicle controlled stopping system of  claim 3  wherein the one or more sections of terrain include a plurality of sections of terrain that each includes one of the cells. 
     
     
         5 . The autonomous vehicle controlled stopping system of  claim 1  wherein the determining of the slope of the terrain for the at least one section includes:
 extracting a covariance matrix of the 3D data points in the subset for the at least one section; 
 extracting a principal eigenvector of the at least one section that points in a direction of a distribution of the 3D data points in the subset for the at least one section; and 
 using, as the slope of the terrain for the at least one section, a ratio between a Z direction component of the principal eigenvector and joint X and Y direction components of the principal eigenvector. 
 
     
     
         6 . The autonomous vehicle controlled stopping system of  claim 1  further comprising:
 one or more GPS antennas mounted at one or more positions on the chassis and capable of receiving GPS signals for use in determining GPS coordinates of at least some of the chassis; and 
 one or more first position sensors mounted on one or more first hydraulic arms between the chassis and a front tool attachment and configured to detect one or more first angles between the chassis and the one or more first hydraulic arms, one or more second position sensors mounted on one or more second hydraulic arms between the chassis and a rear tool attachment and configured to detect one or more second angles between the chassis and the one or more second hydraulic arms, one or more third position sensors mounted on the front tool attachment and configured to detect one or more third angles between the front tool attachment and at least one of the first hydraulic arms, and one or more fourth position sensors mounted on the rear tool attachment and configured to detect one or more fourth angles between the rear tool attachment and at least one of the second hydraulic arms, 
 and wherein the automated operations further include controlling the motion of the powered earth-moving vehicle along the planned travel path using determined GPS coordinates of the at least some of the chassis and using detected first and second and third and fourth angles. 
 
     
     
         7 . The autonomous vehicle controlled stopping system of  claim 1  wherein the control system is configured to implement at least some automated operations of an earth-moving vehicle autonomous operations control system by executing software instructions of the earth-moving vehicle autonomous operations control system, and wherein the automated operations are performed autonomously without receiving human input and without receiving external signals other than GPS signals and real-time kinematic (RTK) correction signals. 
     
     
         8 . The autonomous vehicle controlled stopping system of  claim 1  wherein the powered earth-moving vehicle is one of a bulldozer vehicle or a wheel loader vehicle or a track loader vehicle or a skid steer loader vehicle or an excavator vehicle or a dump truck vehicle. 
     
     
         9 . The autonomous vehicle controlled stopping system of  claim 1  wherein the powered earth-moving vehicle has both a brake pedal and a decelerator pedal, and wherein the activating of the at least one of the brake pedal or the decelerator pedal includes activating both the brake pedal and the decelerator pedal. 
     
     
         10 . A computer-implemented method, comprising:
 obtaining, by one or more LiDAR (light detection and ranging) components mounted on a powered earth-moving vehicle, LiDAR data for one or more areas in one or more directions around the powered earth-moving vehicle on a site, the LiDAR data including a point cloud having a plurality of 3D (three-dimensional) data points on surfaces in the one or more areas, wherein the powered earth-moving vehicle has a chassis and has at least one of tracks or wheels and has controls for manipulating movement of the at least one of the tracks or wheels;   determining, by one or more configured hardware processors on the powered earth-moving vehicle, and for each of one or more sections in the one or more areas and based at least in part on a subset of the 3D data points in that section, one or more attributes of at least one of the surfaces in that section that are based at least in part on differences in height between 3D data points in that subset;   determining, by the one or more configured hardware processors on the powered earth-moving vehicle and while the powered earth-moving vehicle is in motion, that the determined one or more attributes of the at least one surfaces for at least one of the sections satisfy one or more defined criteria for stopping the powered earth-moving vehicle;   determining, by the one or more configured hardware processors on the powered earth-moving vehicle and based at least in part on the determined one or more attributes of the at least one surfaces for the at least one section satisfying the one or more defined criteria, to initiate stopping of the powered earth-moving vehicle before the powered earth-moving vehicle travels over the at least one section; and   activating, by the one or more configured hardware processors on the powered earth-moving vehicle and in response to the determining to initiate the stopping, at least one of the controls to cause the powered earth-moving vehicle to stop.   
     
     
         11 . The computer-implemented method of  claim 10  wherein the one or more directions around the powered earth-moving vehicle include a planned travel path of the powered earth-moving vehicle, wherein the motion of the powered earth-moving vehicle is along the planned travel path, wherein the determining of the one or more attributes of the at least one surfaces in the at least one section include determining a slope of the at least one surfaces of terrain in the at least one section, and wherein the one or more defined criteria for stopping the powered earth-moving vehicle include the determined slope being above a defined slope threshold. 
     
     
         12 . The computer-implemented method of  claim 10  wherein the at least one control manipulates movement of at least one of a brake pedal or a decelerator pedal of the powered earth-moving vehicle, and wherein the activating of the at least one control includes using one or more piston displacement mechanisms on the powered earth-moving vehicle to displace the at least one of the brake pedal or the decelerator pedal. 
     
     
         13 . The computer-implemented method of  claim 10  wherein the powered earth-moving vehicle has both a brake pedal and a decelerator pedal, and wherein displacing of the at least one of the brake pedal or the decelerator pedal includes displacing both the brake pedal and the decelerator pedal. 
     
     
         14 . The computer-implemented method of  claim 10  wherein the powered earth-moving vehicle is one of a bulldozer vehicle or a wheel loader vehicle or a track loader vehicle or a skid steer loader vehicle or an excavator vehicle or a dump truck vehicle, wherein at least one of the one or more hardware processors is a low-voltage microcontroller that is located on the powered earth-moving vehicle and is configured to implement at least some automated operations of an earth-moving vehicle autonomous operations control system by executing software instructions of the earth-moving vehicle autonomous operations control system, and wherein the determining of the one or more attributes of the terrain in each of the one or more sections and the determining that the determined one or more attributes of the terrain for the at least one section satisfy the one or more defined criteria and the determining to initiate the stopping of the powered earth-moving vehicle and the activating are performed autonomously without receiving human input and without receiving external signals other than GPS signals and real-time kinematic (RTK) correction signals. 
     
     
         15 . The computer-implemented method of  claim 10  wherein the activating of the at least one controls includes, until one or more additional criteria related to the motion of the powered earth-moving vehicle are satisfied, applying one or more defined amounts of force to at least one of a brake pedal of the powered earth-moving vehicle or a decelerator pedal of the powered earth-moving vehicle. 
     
     
         16 . The computer-implemented method of  claim 15  wherein the one or more additional criteria related to the motion of the powered earth-moving vehicle include a speed of the powered earth-moving vehicle being below a defined speed threshold, wherein the powered earth-moving vehicle further has one or more tool attachments rotatably coupled to the chassis via one or more hydraulic arms, and wherein the method further comprises, after the speed of the powered earth-moving vehicle is below the defined speed threshold:
 lowering, via at least one piston displacement mechanism, at least one of the tool attachments to be in contact with a surface on which the powered earth-moving vehicle rests; and 
 after the lowering of the at least one of the tool attachments, activating a parking brake of the powered earth-moving vehicle. 
 
     
     
         17 . The computer-implemented method of  claim 10  further comprising dividing the one or more areas into a grid having a plurality of cells, wherein each of the one or more sections include at least one of the cells, and wherein the method further comprises determining that the one or more attributes of the at least one surface for the at least one section satisfy the one or more defined criteria includes:
 determining that the subset of the 3D data points in the at least one section are above a defined minimum quantity threshold; and 
 determining that a difference in height between a lowest of the 3D data points of that subset and a highest of the 3D data points of that subset is above a defined height difference threshold. 
 
     
     
         18 . The computer-implemented method of  claim 17  wherein the one or more sections include a plurality of sections of terrain that each includes one of the cells. 
     
     
         19 . The computer-implemented method of  claim 10  wherein the determining of the one or more attributes of the at least one surface for the at least one section includes determining a slope of terrain for the at least one section by:
 extracting a covariance matrix of the 3D data points in the subset for the at least one section; 
 extracting a principal eigenvector of the at least one section that points in a direction of a distribution of the 3D data points in the subset for the at least one section; and 
 using, as the slope of the terrain for the at least one section, a ratio between a Z direction component of the principal eigenvector and joint X and Y direction components of the principal eigenvector. 
 
     
     
         20 . The computer-implemented method of  claim 10  further comprising controlling the motion of the powered earth-moving vehicle along a planned travel path using determined GPS coordinates of at least some of the chassis from one or more GPS antennas mounted at one or more positions on the chassis, and using first angles that are between the chassis and one or more first hydraulic arms rotatably coupled to the chassis and that are detected from one or more first position sensors mounted on the one or more first hydraulic arms, and second angles that are between the one or more first hydraulic arms and one or more tool attachments coupled to the one or more first hydraulic arms and that are detected from one or more second position sensors mounted on the one or more tool attachments.