US Patent 10471955 Stop sign and traffic light alert

Embodiments relate generally to three-dimensional mapping and more particularly to creating and using three-dimensional feature maps to improve vehicle safety. Features of a road and surrounding area are identified from imaging and telemetry data. One or more constraints such as dimensions or distances of each feature are estimated from the telemetry and imaging data. A feature map is derived from the constraints and the identified features. Some example applications include using the feature map in automatic emergency braking systems or forward collision warning systems.