# US 2023/0057584 A1 · Robot cleaner and method for controlling the same > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2023/0057584 A1 - Document ID: US20230057584A1 - Status: Published application - Kind: A1 - Application number: 17/793,198 - Filed: 2020-05-08 - Published: 2023-02-23 - Earliest claimed: 2020-01-21 - Assignees: LG Electronics Inc. - Applicants: LG Electronics Inc. - Inventors: Jaemin KIM - Web page: https://patentgrep.com/patent/US20230057584A1 ## CPC - A47L 9/2826: {the condition of the floor} - A47L 11/4011: {Regulation of the cleaning machine by electric means; Control systems and remote control systems therefor} - A47L 9/2852: {Elements for displacement of the vacuum cleaner or the accessories therefor, e.g. wheels, casters or nozzles} - G05D 1/0214: {in accordance with safety or protection criteria, e.g. avoiding hazardous areas (monitoring the location of vehicles within a certain area, e.g. forbidden or allowed areas, in traffic control systems for road vehicles G08G1/13)} - G05D 1/0246: {using a video camera in combination with image processing means} - G05D 1/0274: {using mapping information stored in a memory device (navigation using map-matching G01C21/30)} - G06T 7/12: Edge-based segmentation - G06T 7/73: using feature-based methods - G06T 7/74: {involving reference images or patches} - G06V 10/44: Local feature extraction by analysis of parts of the pattern, e.g. by detecting edges, contours, loops, corners, strokes or intersections; Connectivity analysis, e.g. of connected components - G06V 20/56: exterior to a vehicle by using sensors mounted on the vehicle - A47L 2201/04: Automatic control of the travelling movement; Automatic obstacle detection - G06T 2207/10016: Video; Image sequence - G06T 2207/20021: Dividing image into blocks, subimages or windows - G06T 2207/30252: Vehicle exterior; Vicinity of vehicle - A47L: DOMESTIC WASHING OR CLEANING (brushes A46B; cleaning quantities of bottles or of other hollow articles of one kind B08B9/00; laundry D06F); SUCTION CLEANERS IN GENERAL (cleaning in general B08) - G05D: SYSTEMS FOR CONTROLLING OR REGULATING NON-ELECTRIC VARIABLES - G06T: IMAGE DATA PROCESSING OR GENERATION, IN GENERAL - G06V: IMAGE OR VIDEO RECOGNITION OR UNDERSTANDING ## Abstract Provided are a robot cleaner and a method for controlling the same, which are capable of determining the presence or absence of a liquid based on an image captured by a camera. The robot cleaner includes a cleaner body including a traveling part, a camera provided on one surface of the cleaner body and configured to acquire an image of surroundings of the cleaner body, and a controller provided in the cleaner body and configured to control the traveling part. The controller is configured to divide an image acquired by the camera into a plurality of images with respect to a reference line, and determine the presence or absence of a liquid based on two or more images among the plurality of divided images. ## Claims ### Claim 1 A robot cleaner comprising: a cleaner body comprising a traveling part; a camera provided on one surface of the cleaner body and configured to acquire an image of surroundings of the cleaner body; and a controller provided in the cleaner body and configured to control the traveling part, wherein the controller is configured to: divide an image acquired by the camera into a plurality of images with respect to a reference line; and determine the presence or absence of a liquid based on two or more images among the plurality of divided images. ### Claim 2 (depends on 1) The robot cleaner according to claim 1, wherein the reference line is a boundary line between a wall surface and a floor surface in the image acquired by the camera. ### Claim 3 (depends on 1) The robot cleaner according to claim 1, wherein the plurality of images comprise a first image and a second image, and wherein the two or more images are the first image and the second image. ### Claim 4 (depends on 3) The robot cleaner according to claim 3, wherein the controller is configured to acquire a third image in which the second image is symmetrical with respect to the reference line, and determine the presence or absence of the liquid by using the first image and the third image. ### Claim 5 (depends on 4) The robot cleaner according to claim 4, wherein the controller is configured to extract a plurality of first feature points extracted from the first image and a plurality of second feature points extracted from the third image, and determine the presence or absence of the liquid based on matching information about the plurality of second feature points corresponding to the plurality of first feature points. ### Claim 6 (depends on 3) The robot cleaner according to claim 3, wherein the controller is configured to extract a plurality of first feature points extracted from the first image and a plurality of second feature points extracted from the second image, and determine the presence or absence of the liquid based on matching information about the plurality of second feature points corresponding to the plurality of first feature points. ### Claim 7 (depends on 6) The robot cleaner according to claim 6, wherein the controller is configured to make the plurality of second feature points symmetrical with respect to the reference line, and determine the presence or absence of the liquid by using matching information about the plurality of second symmetrical feature points and the plurality of first feature points. ### Claim 8 (depends on 5) The robot cleaner according to claim 5, wherein, when the controller determines that the liquid is present, the controller is configured to acquire a reference feature point located at a shortest distance from the cleaner body in the third image, and calculate the shortest distance based on the reference feature point. ### Claim 9 (depends on 8) The robot cleaner according to claim 8, wherein the reference feature point is one of the plurality of second feature points. ### Claim 10 (depends on 8) The robot cleaner according to claim 8, wherein the controller is configured to acquire the reference feature point separately from the plurality of second feature points. ### Claim 11 (depends on 8) The robot cleaner according to claim 8, wherein the controller is configured to detect an angle from the camera to the reference feature point located at the shortest distance from the cleaner body, and calculate the shortest distance based on a height from the floor surface to the camera. ### Claim 12 (depends on 8) The robot cleaner according to claim 8, wherein the controller is configured to generate a map based on the information acquired from the camera, and display, on the map, an area where the liquid is present, based on the shortest distance. ### Claim 13 (depends on 12) The robot cleaner according to claim 12, wherein the controller is configured to cause the cleaner body to travel while avoiding the area where the liquid is present. ### Claim 14 A method for controlling a robot cleaner, the method comprising: acquiring an image by capturing an image of surroundings through a camera while traveling; dividing the acquired image into a plurality of images based on a reference line; determining the presence or absence of a liquid based on two or more images among the plurality of images; and when it is determined that the liquid is present, displaying, on a map, an area where the liquid is present, and driving the robot cleaner to avoid the area where the liquid is present. ### Claim 15 (depends on 14) The method according to claim 14, wherein the reference line is a boundary line between a wall surface and a floor surface in the image acquired by the camera. ### Claim 16 (depends on 14) The method according to claim 14, wherein the plurality of images comprise a first image and a second image, and wherein the two or more images are the first image and the second image. ### Claim 17 (depends on 16) The method according to claim 16, wherein the determining of the presence or absence of the liquid comprises extracting a plurality of first feature points extracted from the first image and a plurality of second feature points extracted from the second image, and determining the presence or absence of the liquid based on matching information about the plurality of second feature points corresponding to the plurality of first feature points. ### Claim 18 A method for controlling a robot cleaner, the method comprising: acquiring an image by capturing an image of surroundings through a camera while traveling; dividing the acquired image into a first image and a second image based on a reference line; acquiring a third image in which the second image is symmetrical with respect to the reference line; determining the presence or absence of a liquid based on the first image and the third image; and when it is determined that the liquid is present, displaying, on a map, an area where the liquid is present, and driving the robot cleaner to avoid the area where the liquid is present. ### Claim 19 (depends on 18) The method according to claim 18, wherein the determining of the presence or absence of the liquid comprises extracting a plurality of first feature points extracted from the first image and a plurality of second feature points extracted from the third image, and determining the presence or absence of the liquid based on matching information about the plurality of second feature points corresponding to the plurality of first feature points. ### Claim 20 (depends on 18) The method according to claim 18, wherein the reference line is a boundary line between a wall surface and a floor surface in the image acquired by the camera.