Mobile robot and method for controlling same

{
  "publication_number": "US12364379B2",
  "country": "US",
  "kind": "B2",
  "title": "Mobile robot and method for controlling same",
  "abstract": "The present invention relates to a mobile robot and a method for controlling the same. The present invention provides a mobile robot using the rotational force of at least three rotating members as a movement power source and a method for controlling the same, in which the mobile robot is controlled to effectively travel along a set curved driving path and not deviate from the set curved driving path, or to immediately return to the curved driving path when deviating from the set curved driving path.",
  "claims": [
    "1. A mobile robot comprising: a main body; a driving assembly installed on the main body and supplying power for travel of the mobile robot; a first rotating member, a second rotating member and a third rotating member, each rotating member configured to accommodate a first cleaner, a second cleaner, and a third cleaner, respectively, and providing movement power sources for the travel of the mobile robot by performing respective rotational motions about a first rotation axis, a second rotation axis and a third rotation axis, respectively, by power of the driving assembly; and a controller configured to control the driving assembly for the first rotating member and the second rotating member to rotate at different speeds in opposite directions and for the third rotating member to rotate in the same direction as a rotation direction of one of the first rotating member or the second rotating member having a higher rotating speed among the first rotating member and the second rotating member, wherein the controller controls the driving assembly for the third rotating member to rotate at a lower speed than the one of the first or second rotating member having the higher rotating speed at a value of 30% or more of the higher rotating speed, wherein the controller is further configured to: control the rotational speeds the first, second and third rotating members in consideration of a friction level of a ground surface on which the mobile robot travels and whether the respective cleaners are wet or dry during the travel of the mobile robot; and determine the friction levels of the ground surface corresponding to the first rotating member and the ground surface corresponding to the second rotating member by obtaining a first load value applied to the first rotating member and a second load value applied to the second rotating member, wherein the controller is further configured to control the rotational speeds of the first rotating member and the second rotating member in consideration of the first load value and the second load value for the mobile robot to maintain a preset curved travel direction or travel angle with respect to a forward or backward direction, and when the first and second load values are lower than a preset reference value, the rotational speed of the third rotating member is at a range of 50% to 80% of the higher rotating speed of the first or second rotating member.",
    "2. The mobile robot of claim 1, wherein the first, second and third rotation axes are formed for the first, second and third rotating members to be disposed adjacent to one another.",
    "3. The mobile robot of claim 2, wherein the first rotation axis corresponding to the first rotating member and the second rotation axis corresponding to the second rotating member are each inclined to have a predetermined angle with respect to a central axis, which corresponds to a vertical axis of the mobile robot, for the first rotating member and the second rotating member to each to be disposed at an angle with respect to a ground surface, wherein the third rotation axis corresponding to the third rotating member is parallel to the central axis for the third rotating member to be disposed parallel to the ground surface.",
    "4. The mobile robot of claim 1, further comprising a detection sensor capable of detecting the preset curved travel direction or travel angle, wherein the controller controls the rotational speed of at least one of the first, second and third rotating members for a travel direction of the mobile robot to maintain the preset curved travel direction or travel angle based on a signal of the detection sensor in a case where the travel direction of the mobile robot deviates from the preset curved travel direction or travel angle.",
    "5. The mobile robot of claim 4, wherein the detection sensor includes at least one of an acceleration sensor and a gyro sensor.",
    "6. The mobile robot of claim 1, wherein the controller determines whether the respective cleaners are wet or dry by any one of a signal received from an external remote controller and detection of a predetermined color corresponding to each of the wet cleaner and the dry cleaner.",
    "7. The mobile robot of claim 1, wherein when the first and second load values are higher than the preset reference value, the rotational speed of the third rotating member is at a range of 50% to less than 100% of the higher rotating speed of the first or second rotating member.",
    "8. The mobile robot of claim 1, wherein when the respective cleaners are determined to be wet, the rotational speed of the third rotating member is at a range of 50% to less than 100% of the higher rotating speed of the first or second rotating member."
  ],
  "description_excerpt": "The present invention relates to a mobile robot, and more particularly, to a mobile robot traveling autonomously by including at least three rotating members, and a method for controlling the same.\n\nDue to a recent technological development, there is not only a rapid development in technology of a mobile robot, but also very diverse utilizations and applications of the mobile robot. A representative example may be a robot cleaner which may perform cleaning while traveling autonomously without a user's manual operation.\n\nA related market spotlights a robot cleaner which may use a rotational force of a rotating member to which a wet and/or dry cleaner (e.g., mop) is attached as its movement power source without wheels among various robot cleaners.\n\nThis robot cleaner may remove a foreign material or ingrained dirt adhered to a floor surface better than a robot cleaner traveling using wheels because this cleaner exerts more adhesive and frictional forces on the floor surface (i.e., surface to be cleaned).\n\nHowever, the conventional robot cleaner using the rotational force of the rotating member may generally have two rotating members, and the floor surface existing between the two rotating members may be often excluded from its cleaning region.\n\nTherefore, the conventional robot cleaner using the rotational force of the rotating members may have superior cleaning power than the robot cleaner traveling using wheels, and still have a technical limitation in guaranteeing perfect cleaning power.",
  "cpc": [
    "A47L 11/4011",
    "A47L 11/282",
    "A47L 11/4038",
    "A47L 11/4061",
    "A47L 11/4066",
    "A47L 11/4069",
    "A47L 2201/04",
    "A47L 2201/06",
    "B25J 11/0085",
    "B25J 19/02",
    "B25J 5/00",
    "B25J 9/16",
    "B25J 9/1633",
    "B25J 9/1679",
    "G05D 1/0212",
    "G05D 1/027",
    "G05D 1/648"
  ],
  "ipc": [
    "A47L 11/282",
    "A47L 11/40",
    "G05D 1/00"
  ],
  "assignees": [
    "Everybot Inc"
  ],
  "inventors": [
    "Woo Chul Jung",
    "Bong Yun KIM",
    "Hwan Joo KIM"
  ],
  "filing_date": "2020-12-07",
  "publication_date": "2025-07-22",
  "grant_date": "2025-07-22",
  "priority_date": "2019-12-24",
  "application_number": "US-202017788094-A",
  "family_id": "76574423",
  "cited_by_count": 0,
  "citations": [
    "JP2006061285A",
    "EP2875768A1",
    "US20150190028A1",
    "US20180028033A1",
    "KR20180087778A",
    "KR20180092433A",
    "US20190033869A1",
    "KR101966083B1",
    "KR20190123882A"
  ]
}