# US 8,751,154 B2 · Enhanced clear path detection in the presence of traffic infrastructure indicator > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,751,154 B2 - Document ID: US8751154B2 - Status: Granted - Kind: B2 - Application number: 12/581,849 - Filed: 2009-10-19 - Published: 2010-04-22 - Granted: 2014-06-10 - Earliest claimed: 2008-04-24 - Assignees: GM Global Technology Operations LLC - Applicants: Wende Zhang; Sanjeev M. Naik - Inventors: Wende Zhang; Sanjeev M. Naik - Web page: https://patentgrep.com/patent/US8751154B2 ## CPC - G08G 1/00: Traffic control systems for road vehicles (arrangement of road signs or traffic signals E01F9/00 {; automatic vehicle control B62D}) - B60W 30/09: Taking automatic action to avoid collision, e.g. braking and steering - G06V 20/58: Recognition of moving objects or obstacles, e.g. vehicles or pedestrians; Recognition of traffic objects, e.g. traffic signs, traffic lights or roads - G06V 20/582: {of traffic signs} - G06V 20/584: {of vehicle lights or traffic lights} - G06V 20/588: {Recognition of the road, e.g. of lane markings; Recognition of the vehicle driving pattern in relation to the road} - G08G 1/163: {involving continuous checking} - B60W 2420/403: Image sensing, e.g. optical camera - G08G: TRAFFIC CONTROL SYSTEMS (guiding railway traffic, ensuring the safety of railway traffic B61L; arrangement of road signs or traffic signals E01F9/00; radar or analogous systems, sonar systems, lidar systems specially adapted for traffic control G01S13/91, G01S15/88, G01S17/88; {radar or analogous systems, sonar systems, lidar systems specially adapted for anti-collision purposes G01S13/93, G01S15/93, G01S17/93}) - B60W: CONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT - G06V: IMAGE OR VIDEO RECOGNITION OR UNDERSTANDING ## Abstract A method for detecting a clear path of travel for a vehicle utilizing analysis of a plurality of images generated by a camera device located upon the vehicle includes monitoring the images. The images are analyzed including determining a clear path upon which a potential road surface can be estimated from other portions of the images that do not indicate a potential road surface, and determining an image of a traffic infrastructure indication. The method further includes determining the content of the traffic infrastructure indication, modifying the clear path based upon the content of the traffic infrastructure indication, and utilizing the modified clear path in navigation of the vehicle. ## Claims ### Claim 1 Method for detecting a clear path of travel for a vehicle utilizing analysis of a plurality of images generated by a camera device located upon the vehicle, the images generated by the camera device are input to a processing module configured to execute the method comprising: monitoring the images; analyzing the images comprising determining a clear path upon which a potential road surface can be estimated from other portion of the images that do not indicate a potential road surface; determining an image of a traffic infrastructure indication; determining the content of the traffic infrastructure indication; iteratively fusing the content of the traffic infrastructure indication and the determined clear path to generate a modified clear path, comprising determining, during a first iteration, that the determined clear path describes a section along the potential road surface of a special zone that invalidates the content of the traffic infrastructure indication and enhancing the content of the traffic infrastructure indication to correspond with the section along the potential road surface or the special zone described by the determined clear path, determining, during a second iteration, that the enhanced content of the traffic infrastructure indication describes a threshold condition, the threshold condition selected to minimize at least one of non-critical and non-desirable distractions upon the vehicle operating in one of autonomous and semi-autonomous driving modes, and modifying the clear path based upon the enhanced content of the traffic infrastructure indication; and utilizing the modified clear path in navigation of the vehicle. ### Claim 2 (depends on 1) The method of claim 1, wherein determining the image of the traffic infrastructure indication comprises determining a roadside sign. ### Claim 3 (depends on 2) The method of claim 2, wherein the roadside sign comprises a stop sign. ### Claim 4 (depends on 3) The method of claim 3, further comprising: determining, during the first iteration, that the determined clear path does not describe the section along the potential road surface or the special zone that invalidates the content of the traffic infrastructure indications and modifying the clear path based upon the stop sign comprising indicating road past the stop sign to be not clear path until the vehicle stops at the stop sign. ### Claim 5 (depends on 2) The method of claim 2, wherein the roadside sign comprises a road geometry sign. ### Claim 6 (depends on 2) The method of claim 2, wherein the roadside sign comprises a road construction indication. ### Claim 7 (depends on 1) The method of claim 1, wherein determining the image of the traffic infrastructure indication comprises determining a traffic signal indication. ### Claim 8 (depends on 7) The method of claim 7, further comprising: determining, during the first iteration, that the determined clear path does not describe the section along the potential road surface or the special zone that invalidates the content of the traffic infrastructure indications and modifying the clear path based upon the traffic signal indication comprising indicating road past the traffic signal indication indicates a stop condition. ### Claim 9 (depends on 1) The method of claim 1, wherein determining the content of the traffic infrastructure indication comprises storing the image of the traffic infrastructure indicator in a database for comparison and cross referencing for context. ### Claim 10 (depends on 1) The method of claim 1, wherein determining the content of the traffic infrastructure indication comprises utilizing pattern recognition to determine the content of the traffic infrastructure indication. ### Claim 11 (depends on 1) The method of claim 1, wherein determining the content of the traffic infrastructure indication comprises monitoring a vehicle-to-infrastructure communication link. ### Claim 12 (depends on 1) The method of claim 1, further comprising monitoring a GPS digital map device; and wherein determining the image of the traffic infrastructure indication comprises determining a traffic direction signal based upon data from the GPS digital map device. ### Claim 13 A system for detecting a clear path of travel for a vehicle utilizing analysis of a plurality of images generated by a camera device located upon the vehicle, the system comprising: a camera device located upon the vehicle and configured to generate a plurality of images; a control module configured to monitor the images and analyze the images from the camera device, wherein analyzing the images from the camera device comprises determining a clear path upon which a potential road surface can be estimated from other portions of the image that do not indicate a potential road surface; determining an image of a traffic infrastructure indication; determining the content of the traffic infrastructure indication; iteratively fusing the content of the traffic infrastructure indication and the determined clear path to generate a modified clear path, comprising determining, during a first iteration, that the determined clear path describes a section along the potential road surface of a special zone that invalidates the content of the traffic infrastructure indication and enhancing the content of the traffic infrastructure indication to correspond with the section along the potential road surface or the special zone described by the determined clear path, determining, during a second iteration, that the enhanced content of the traffic infrastructure indication describes a threshold condition, the threshold condition selected to minimize at least one of non-critical and non-desirable distractions upon the vehicle operating in one of autonomous and semi-autonomous driving modes, and modifying the clear path based upon the enhanced content of the traffic infrastructure indication; and utilizing the modified clear path in navigation of the vehicle. ### Claim 14 (depends on 13) The system of claim 13, further comprising an autonomous steering system operating based upon the analyzing the images from the camera device.