Traffic light occlusion detection for autonomous vehicle

A method performed by an autonomous vehicle, the method comprising:

• generating a three-dimensional point cloud by a sensor system of the autonomous vehicle;
• converting the three-dimensional point cloud to a two-dimensional range image, the two-dimensional range image comprises distance values to objects in an environment nearby the autonomous vehicle;
• detecting a first region in the two-dimensional range image having distance values corresponding to an expected distance to a traffic light and a second region in the two-dimensional range image having distance values closer than the expected distance to the traffic light;
• defining an occlusion polygon around the second region;
• identifying an illuminated configuration of the traffic light based on an output from a camera of the autonomous vehicle, wherein a region of the output from the camera corresponding to the occlusion polygon is excluded from being used to identify the illuminated configuration of the traffic light;
• and
• controlling a mechanical system of the autonomous vehicle based upon the illuminated configuration of the traffic light.

An autonomous vehicle comprising:

• a computer-readable storage medium that comprises instructions that, when executed by one or more processors, cause the one or more processors to perform actions comprising:
• receiving a three-dimensional point cloud from a sensor system of the autonomous vehicle;
• converting the three-dimensional point cloud to a two-dimensional range image, the two-dimensional range image comprises distance values to objects in an environment nearby the autonomous vehicle;
• detecting a region in the two-dimensional range image having distance values closer than an expected distance to a traffic light;
• defining an occlusion polygon around the region;
• identifying an illuminated configuration of the traffic light based on an output from a camera of the autonomous vehicle, wherein a region of the output from the camera corresponding to the occlusion polygon is excluded from being used to identify the illuminated illumination configuration of the traffic light;
• and
• controlling a mechanical system of the autonomous vehicle based upon the illuminated configuration of the traffic light.