# US 12,181,567 B2 · Object detection method and object detecting device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,181,567 B2 - Document ID: US12181567B2 - Status: Granted - Kind: B2 - Application number: 18/280,022 - Filed: 2021-03-03 - Published: 2024-07-25 - Granted: 2024-12-31 - Earliest claimed: 2021-03-03 - Assignees: Nissan Motor Co., Ltd. - Applicants: Nissan Motor Co., Ltd. - Inventors: Takashi Ikegami; Kuniaki Noda - Web page: https://patentgrep.com/patent/US12181567B2 ## CPC - G01S 13/867: {Combination of radar systems with cameras} - G08G 1/166: {for active traffic, e.g. moving vehicles, pedestrians, bikes} - G01J 5/00: Radiation pyrometry, e.g. infrared or optical thermometry - G01S 13/58: Velocity or trajectory determination systems; Sense-of-movement determination systems - G01S 13/931: of land vehicles - G06V 20/56: exterior to a vehicle by using sensors mounted on the vehicle - G01J 2005/0077: {Imaging} - G01S 2013/93275: {in the bumper area} - G08G 1/048: with provision for compensation of environmental or other condition, e.g. snow, vehicle stopped at detector - G01S: RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES - 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}) - G01J: MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY (light sources F21, H01J, H01K, H05B; investigating properties of materials by optical means G01N) - G06V: IMAGE OR VIDEO RECOGNITION OR UNDERSTANDING ## Abstract An object detection method includes irradiating a position in front of a host-vehicle with an electromagnetic wave, and detecting an object in front of the host-vehicle based on a reflected wave of the electromagnetic wave. The object detection method further includes capturing an image of the position in front of the host-vehicle to acquire an image, and determining whether the object is floating matters based on the acquired image if a state where the object is not detected changes to a state where the object is detected. ## Claims ### Claim 1 An object detection method comprising: irradiating a position in front of a host-vehicle with an electromagnetic wave; detecting an object in front of the host-vehicle based on a reflected wave of the electromagnetic wave; capturing an image of the position in front of the host-vehicle when the object is not detected to acquire a first image that is an optical image; capturing an image of the position in front of the host-vehicle when the object is detected to acquire a second image that is an optical image; calculating a difference between the first image and the second image when a state where the object is not detected changes to a state where the object is detected; and determining that the object is floating matters if the difference is less than a threshold difference. ### Claim 2 (depends on 1) The object detection method according to claim 1, comprising: acquiring an infrared image in addition to the optical image; calculating a temperature of the object based on luminance of infrared light at a position corresponding to the object in the infrared image; and determining that the object is floating matters if the difference between the first image and the second image is equal to or greater than the threshold difference and the temperature of the object is equal to or higher than a threshold temperature. ### Claim 3 (depends on 2) The object detection method according to claim 2, comprising: calculating an amount of change in the temperature of the object if the difference between the first image and the second image is equal to or greater than the threshold difference and the temperature of the object is lower than the threshold temperature; and determining that the object is floating matters if the amount of change in the temperature of the object is equal to or greater than a threshold amount of change. ### Claim 4 (depends on 1) The object detection method according to claim 1, wherein the object is located behind a preceding vehicle in front of the host-vehicle, and the object detection method comprises: if the preceding vehicle starts moving from a stopped state, determining whether the object is floating matters until a threshold time elapses from when the preceding vehicle has started moving. ### Claim 5 (depends on 1) The object detection method according to claim 1, wherein the object is located behind a preceding vehicle in front of the host-vehicle, and the object detection method comprises: determining whether the object is floating matters if a speed of the preceding vehicle is less than a threshold speed. ### Claim 6 (depends on 1) The object detection method according to claim 1, wherein the object is located behind a preceding vehicle in front of the host-vehicle, and the object detection method comprises: if an exhaust pipe of the preceding vehicle is detected from the optical image or an infrared image, setting a range of the optical image or a range of the infrared image for determining whether the object is floating matters, according to a position of the exhaust pipe of the preceding vehicle. ### Claim 7 (depends on 1) The object detection method according to claim 1, comprising: tracking the floating matters. ### Claim 8 An object detection method comprising: irradiating a position in front of a host-vehicle with an electromagnetic wave; detecting an object in front of the host-vehicle based on a reflected wave of the electromagnetic wave; capturing an image of the position in front of the host-vehicle to acquire an infrared image; calculating an amount of change in a temperature of the object based on a change in luminance of infrared light at a position corresponding to the object in the infrared image when a state where the object is not detected changes to a state where the object is detected; and determining that the object is floating matters if the amount of change in the temperature of the object is equal to or greater than a threshold amount of change. ### Claim 9 (depends on 8) The object detection method according to claim 8, comprising: calculating the temperature of the object based on the luminance of the infrared light at the position corresponding to the object in the infrared image; determining that the object is floating matters if the temperature of the object is equal to or higher than a threshold temperature; calculating the amount of change in the temperature of the object if the temperature of the object is lower than the threshold temperature; and determining that the object is floating matters if the amount of change in the temperature of the object is equal to or greater than the threshold amount of change. ### Claim 10 (depends on 9) The object detection method according to claim 9, wherein the threshold temperature is set to be higher as an outside air temperature increases. ### Claim 11 An object detecting device comprising: a sensor that irradiates a position in front of a host-vehicle with an electromagnetic wave and detects an object in front of the host-vehicle based on a reflected wave of the electromagnetic wave; a camera that captures an image of the position in front of the host-vehicle to acquire an optical image; and a controller configured to: acquire a first image that is the optical image captured when the object is not detected; acquire a second image that is the optical image captured when the object is detected; calculate a difference between the first image and the second image when a state where the object is not detected changes to a state where the object is detected; and determine that the object is floating matters if the difference is less than a threshold difference. ### Claim 12 An object detecting device comprising: a sensor that irradiates a position in front of a host-vehicle with an electromagnetic wave and detects an object in front of the host-vehicle based on a reflected wave of the electromagnetic wave; a camera that captures an image of the position in front of the host-vehicle to acquire an infrared image; and a controller configured to: calculate an amount of change in a temperature of the object based on a change in luminance of infrared light at a position corresponding to the object in the infrared image when a state where the object is not detected changes to a state where the object is detected; and determine that the object is floating matters if the amount of change in the temperature of the object is equal to or greater than a threshold amount of change.