US 12,253,373 B2
Determining vehicle turn difficulty using overhead images
Miles Carlsten, Kirkland, WA (US)
Assigned to Trimble Inc., Westminster, CO (US)
Filed by Trimble Inc., Sunnyvale, CA (US)
Filed on Aug. 18, 2022, as Appl. No. 17/890,573.
Prior Publication US 2024/0060784 A1, Feb. 22, 2024
Int. Cl. G01C 21/34 (2006.01); G01C 21/36 (2006.01); G06V 10/70 (2022.01); G06V 20/10 (2022.01); G06V 20/13 (2022.01); H04W 4/40 (2018.01)
CPC G01C 21/3461 (2013.01) [G01C 21/3602 (2013.01); G01C 21/3647 (2013.01); G06V 10/70 (2022.01); G06V 20/13 (2022.01); G06V 20/182 (2022.01); H04W 4/40 (2018.02)] 20 Claims
OG exemplary drawing
 
1. A method comprising:
obtaining an overhead image of a road intersection;
predicting a footprint of the road intersection using the overhead image;
analyzing the footprint of the road intersection to calculate one or more distances associated with a turn at the road intersection, wherein analyzing the footprint of the road intersection includes:
identifying an entry road and an exit road associated with the turn based on the footprint of the road intersection;
calculating a set of road vectors based on the footprint of the road intersection, the set of road vectors including a first road vector for the entry road and a second road vector for the exit road; and
fitting a hyperbolic curve based on the set of road vectors, wherein the hyperbolic curve intersects an edge of the road intersection, and wherein the one or more distances are calculated based on a focus point of the hyperbolic curve; and
calculating a turn difficulty value associated with the turn based on the one or more distances for the turn.