Methods and devices for determining movements of an object in an environment

An autonomous vehicle, comprising:

• one or more depth sensors;
• and
• a control system configured to:
• receive a first set of points based on detection of an environment by the one or more depth sensors on the autonomous vehicle during a first time period;
• select a plurality of points from the first set of points that form a first point cloud representing an object in the environment;
• receive a second set of points based on detection of the environment by the one or more depth sensors during a second time period, wherein the second time period is after the first time period;
• select a plurality of points from the second set of points that form a second point cloud representing the object in the environment;
• determine a transformation between the selected points from the first set of points that form the first point cloud representing the object in the environment and the selected from the second set of points that form the second point cloud representing the object in the environment;
• use the transformation to determine a velocity of the object;
• and
• control the autonomous vehicle based at least in part on the velocity of the object.

A non-transitory computer readable medium having stored therein instructions, that when executed by a control system of an autonomous vehicle, cause the control system to perform functions comprising:

• receiving a first set of points based on detection of an environment of the autonomous vehicle by one or more sensors on the autonomous vehicle during a first time period;
• selecting a plurality of points from the first set of points that form a first point cloud representing an object in the environment;
• receiving a second set of points based on detection of the environment by the one or more sensors on the autonomous vehicle during a second time period, wherein the second time period is after the first period;
• selecting a plurality of points from the second set of points that form a second point cloud representing the object in the environment;
• determining a transformation between the selected points from the first set of points that form the first point cloud representing the object in the environment and the selected points from the second set of points that form the second point cloud representing the object in the environment;
• using the transformation to determine a velocity of the object;
• and
• controlling the autonomous vehicle based at least in part on the velocity of the object.