Object tracking by generating velocity grids

A system for creating a velocity grid using a simulated environment for use by an autonomous vehicle, the system comprising:

• one or more processors;
• a computer-readable medium comprising instructions stored therein, which when executed by one or more processors, cause the processors to:
• simulate a road scenario with simulated non-player characters,
• collect first LiDAR data from simulated LiDAR sensors in the simulated road scenario, wherein the collected first LiDAR data comprises a first plurality of points that are representative of a first simulated object at a first three-dimensional (3D) location and a first time, a first point representative of a portion of the first simulated object,
• transform the first plurality of points from a simulated-scene frame-of-reference to a first simulated object frame-of-reference,
• simulate the first simulated object to move from the first 3D location to a second 3D location within the simulated road scenario between the first time and a second time,
• collect second LiDAR data from the simulated LiDAR sensors in the simulated road scenario at the second time, wherein the collected second LiDAR data comprises a second plurality of points representative of the first simulated object at the second 3D location and a second time, a second point representative of a portion of the first simulated object,
• transform the second plurality of points from the first simulated object frame-of-reference back to the simulated-scene frame-of-reference,
• determine a distance between the first point representative of a portion of the first simulated object and the second point representative of a portion of the first simulated object during the simulated movement of the first simulated object
• calculate the velocity of the portion on the first simulated object in the simulated-scene frame-of-reference during a simulated movement of the first simulated object from the first 3D location to the second 3D location based upon the determined distance, and
• encode the velocity in association with the first point prior to the simulated movement of the simulated object with respect to a second point after the simulated movement of the first simulated object in a 3D velocity grid for the simulated objects.

A non-transitory computer-readable storage medium comprising instructions stored therein, which when executed by one or more processors, cause the processors to:

• simulate a road scenario with simulated non-player characters,
• collect first LiDAR data from simulated LiDAR sensors in the simulated road scenario, wherein the collected first LiDAR data comprises a first plurality of points that are representative of a first simulated object at a first three-dimensional (3D) location and a first time, a first point representative of a portion of the first simulated object,
• transform the first plurality of points from a simulated-scene frame-of-reference to a first simulated object frame-of-reference,
• simulate the first simulated object to move from the first 3D location to a second 3D location within the simulated road scenario between the first time and a second time,
• collect second LiDAR data from the simulated LiDAR sensors in the simulated road scenario at the second time, wherein the collected second LiDAR data comprises a second plurality of points representative of the first simulated object at the second 3D location and a second time, a second point representative of a portion of the first simulated object,
• transform the second plurality of points from the first simulated object frame-of-reference back to the simulated-scene frame-of-reference,
• determine a distance between the first point representative of a portion of the first simulated object and the second point representative of a portion of the first simulated object during the simulated movement of the first simulated object;
• calculate the velocity of the portion on the first simulated object in the simulated-scene frame-of-reference during a simulated movement of the first simulated object from the first 3D location to the second 3D location based upon the determined distance, and
• encode the velocity in association with the first point prior to the simulated movement of the simulated object with respect to a second point after the simulated movement of the first simulated object in a 3D velocity grid for the simulated objects.