# US 12,004,706 B2 · Robotic cleaner > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,004,706 B2 - Document ID: US12004706B2 - Status: Granted - Kind: B2 - Application number: 17/135,275 - Filed: 2020-12-28 - Published: 2021-04-22 - Granted: 2024-06-11 - Earliest claimed: 2017-09-07 - Assignees: SharkNinja Operating LLC - Applicants: SharkNinja Operating, LLC - Inventors: Melinda L. Liggett; Isaku D. Kamada; Frederick K. Hopke; Gan Sin Huat; Charles Fiebig; Scott Connor; Alan Ai - Web page: https://patentgrep.com/patent/US12004706B2 ## CPC - A47L 9/2852: {Elements for displacement of the vacuum cleaner or the accessories therefor, e.g. wheels, casters or nozzles} - A47L 9/009: {Carrying-vehicles; Arrangements of trollies or wheels; Means for avoiding mechanical obstacles} - A47L 9/2805: {Parameters or conditions being sensed} - A47L 2201/00: Robotic cleaning machines, i.e. with automatic control of the travelling movement or the cleaning operation - A47L 2201/04: Automatic control of the travelling movement; Automatic obstacle detection - 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) ## Abstract A robotic cleaner may include a housing, a bumper, driven wheels, and a controller. The bumper can be coupled to a front of the housing. The bumper may include a plurality of projections extending from a top edge of the bumper and above a top surface of the housing. The projections may include at least one leading projection proximate a forward most portion of the bumper and at least two side projections on each respective side of the bumper. The driven wheels may be rotatably mounted to the housing. The controller may be for controlling at least the driven wheels. ## Claims ### Claim 1 A robotic cleaner comprising: a first driven wheel and a second driven wheel, each driven wheel being biased toward an extended position; a first wheel drop sensor corresponding to the first driven wheel and a second wheel drop sensor corresponding to the second driven wheel, each wheel drop sensor being configured to detect when a corresponding driven wheel is in the extended position; and a controller communicatively coupled to the first and second wheel drop sensors, the controller being configured to determine that the robotic cleaner is perched on a cliff in response to only one of the first wheel drop sensor detecting that the first driven wheel is in the extended position or the second wheel drop sensor detecting that the second driven wheel is in the extended position, wherein, in response to the first wheel drop sensor detecting that the first driven wheel is in the extended position and the controller determining that the robotic cleaner is perched on the cliff, the controller is configured to: cause: the first driven wheel to rotate in a rearward rotation direction for a predetermined time; and the second driven wheel to discontinue rotation while the first driven wheel rotates in the rearward rotation direction for the predetermined time; and determine the robotic cleaner is stuck on the cliff when the predetermined time has elapsed and the first wheel drop sensor indicates the first driven wheel is in the extended position. ### Claim 2 (depends on 1) The robotic cleaner of claim 1 further comprising a rotatable side brush, the rotatable side brush including a first group of bristles and a second group of bristles, the first group of bristles having a length longer than that of the second group of bristles. ### Claim 3 (depends on 2) The robotic cleaner of claim 2 further comprising a cliff sensor configured to detect a presence of a floor, wherein, during rotation of the rotatable side brush, the first group of bristles passes between the cliff sensor and the floor and the second group of bristles does not pass between the cliff sensor and the floor. ### Claim 4 (depends on 2) The robotic cleaner of claim 2, wherein the second group of bristles is stiffer than the first group of bristles. ### Claim 5 (depends on 1) The robotic cleaner of claim 1 further comprising a non-driven wheel. ### Claim 6 (depends on 5) The robotic cleaner of claim 5, further comprising optical rotation sensors communicatively coupled to the controller and optically coupled to the non-driven wheel for sensing rotation of the non-driven wheel. ### Claim 7 (depends on 6) The robotic cleaner of claim 6, wherein the optical rotation sensors are coupled together in an OR logic configuration. ### Claim 8 (depends on 1) The robotic cleaner of claim 1, further comprising a bumper, the bumper being movable along at least two axes. ### Claim 9 A robotic cleaner comprising: a first driven wheel and a second driven wheel, each driven wheel being mounted on a respective suspension system, each suspension system configured to bias a corresponding driven wheel toward an extended position; a first wheel drop sensor corresponding to the first driven wheel and a second wheel drop sensor corresponding to the second driven wheel, each wheel drop sensor being configured to detect when a corresponding driven wheel is in the extended position; and a controller communicatively coupled to the first and second wheel drop sensors, the controller being configured to determine that the robotic cleaner is perched on a cliff in response to only one of the first wheel drop sensor detecting that the first driven wheel is in the extended position or the second wheel drop sensor detecting that the second driven wheel is in the extended position, wherein, in response to the first wheel drop sensor detecting that the first drive wheel is in the extended position and the controller determining that the robotic cleaner is perched on the cliff, the controller is configured to: cause: the first driven wheel to alternate between rotating in a forward rotating direction and a rearward rotation direction for a predetermine time; and the second driven wheel to discontinue rotation while the first driven wheel rotates in the forward and the rearward rotation directions for the predetermined time; and determine the robotic cleaner is stuck on the cliff when the predetermined time has elapsed and the first wheel drop sensor indicates the first driven wheel is in the extended position. ### Claim 10 (depends on 9) The robotic cleaner of claim 9, wherein each suspension system includes a pivoting gearbox. ### Claim 11 (depends on 9) The robotic cleaner of claim 9 further comprising a rotatable side brush, the rotatable side brush including a first group of bristles and a second group of bristles, the first group of bristles having a length longer than that of the second group of bristles. ### Claim 12 (depends on 11) The robotic cleaner of claim 11 further comprising a cliff sensor configured to detect a presence of a floor, wherein, during rotation of the rotatable side brush, the first group of bristles passes between the cliff sensor and the floor and the second group of bristles does not pass between the cliff sensor and the floor. ### Claim 13 (depends on 11) The robotic cleaner of claim 11, wherein the second group of bristles is stiffer than the first group of bristles. ### Claim 14 (depends on 9) The robotic cleaner of claim 9 further comprising a non-driven wheel. ### Claim 15 (depends on 14) The robotic cleaner of claim 14, further comprising optical rotation sensors communicatively coupled to the controller and optically coupled to the non-driven wheel for sensing rotation of the non-driven wheel. ### Claim 16 (depends on 15) The robotic cleaner of claim 15, wherein the optical rotation sensors are coupled together in an OR logic configuration. ### Claim 17 (depends on 9) The robotic cleaner of claim 9, further comprising a bumper, the bumper being movable along at least two axes. ### Claim 18 (depends on 17) The robotic cleaner of claim 17, wherein movement of the bumper causes one or more switches to be actuated. ### Claim 19 A robotic cleaner comprising: a first driven wheel and a second driven wheel, each driven wheel being biased toward an extended position; a first wheel drop sensor corresponding to the first driven wheel and a second wheel drop sensor corresponding to the second driven wheel, each wheel drop sensor being configured to detect when a corresponding driven wheel is in the extended position; and a controller communicatively coupled to the first and second wheel drop sensors, wherein, in response to the first wheel drop sensor detecting that the first driven wheel is in the extended position, the controller is configured to cause: the first driven wheel to alternate between rotating in a forward rotation direction and a rearward rotation direction for a predetermined time; and the second driven wheel to discontinue rotation while the first driven wheel rotates in the forward and the rearward rotation directions for the predetermined time. ### Claim 20 (depends on 19) The robotic cleaner of claim 19, wherein the controller is further configured to determine that the robotic cleaner is stuck when the predetermined time has elapsed and the first wheel drop sensor indicates the first driven wheel is in the extended position.