Cleaning method for a robotic cleaning device

• US 10,678,251 B2
• Filed: 12/16/2014
• Issued: 06/09/2020
• Est. Priority Date: 12/16/2014
• Status: Active Grant

• Current Assignee: Aktiebolaget Electrolux
• Original Assignee: Aktiebolaget Electrolux
• Inventors: Haegermarck, Anders, Lindhe, Magnus
• Primary Examiner(s): Jen, Ian
• Application Number:
  US15/535,506
• Publication Number:
  US 20170344013A1
• Time in Patent Office: 2,002 Days
• CPC Class Codes: A47L 11/24 Floor-sweeping machines, motor-driven
• CPC Class Codes: A47L 11/28 Floor-scrubbing machines, motor-driven A47L11/29 takes precedence
• CPC Class Codes: A47L 11/4011 Regulation of the cleaning machine by electric means; Control systems and remote control systems therefor
• CPC Class Codes: A47L 11/4061 Steering means; Means for avoiding obstacles; Details related to the place where the driver is accommodated
• CPC Class Codes: A47L 2201/04 Automatic control of the travelling movement; Automatic obstacle detection
• CPC Class Codes: A47L 5/22 with rotary fans
• CPC Class Codes: A47L 9/009 Carrying-vehicles; Arrangements of trollies or wheels; Means for avoiding mechanical obstacles
• CPC Class Codes: A47L 9/0411 driven by electric motor
• CPC Class Codes: A47L 9/0477 Rolls
• CPC Class Codes: A47L 9/2826 the condition of the floor
• CPC Class Codes: A47L 9/2852 Elements for displacement of the vacuum cleaner or the accessories therefor, e.g. wheels, casters or nozzles
• CPC Class Codes: G05D 1/0219 ensuring the processing of the whole working surface
• CPC Class Codes: G05D 1/0227 using mechanical sensing means, e.g. for sensing treated area
• CPC Class Codes: G05D 1/0234 using optical markers or beacons optical beacons per se G01S1/70
• CPC Class Codes: G05D 1/0238 using obstacle or wall sensors G05D1/0246 and G05D1/0289 take precedence; lidar systems designed for anti-collision purposes G01S17/93
• CPC Class Codes: G05D 1/0272 comprising means for registering the travel distance, e.g. revolutions of wheels measuring distance traversed on the ground by vehicles, e.g. using odometers G01C22/00
• CPC Class Codes: G05D 1/0274 using mapping information stored in a memory device navigation using map-matching G01C21/30

Abstract

A method of operating a robotic cleaning device over a surface to be cleaned, the method being performed by the robotic cleaning device. The method includes: following a boundary of a first object while registering path markers including positional information at intervals on the surface; tracing previously registered path markers at an offset upon encountering one or more of the previously registered path markers; and switching from tracing the previously registered path markers to following an edge of a second object upon detection of the second object.

Claims

1. A method of operating a robotic cleaning device over a surface to be cleaned, the method being performed by the robotic cleaning device, the method comprising:

following a boundary of a first object while registering path markers at intervals on the surface, the registered path markers are virtual markers stored in a memory device of the robotic cleaning device, the virtual markers including positional data indicating respective positions of the robotic cleaning device detected by a sensor;

tracing the registered path markers at an offset upon encountering one or more of the registered path markers; and

switching from tracing the registered path markers to following an edge of a second object upon detection of the second object.

2. The method according to claim 1, further comprising following the edge of the second object until the registered path markers are again encountered.

3. The method according to claim 1, further comprising following the edge of the second object until the second object is encircled.

4. The method according to claim 1, further comprising recognizing a loop defining an area to be cleaned upon encountering one or more of the registered path markers, wherein the loop comprises a plurality of the registered path markers.

5. The method according claim 4, comprising simplifying the loop for generating an efficient cleaning pattern.

6. The method according to claim 5, wherein the simplifying comprises splitting the loop into a plurality of loops defining a plurality of areas to be cleaned, so that the robotic cleaning device can clean the areas one after the other.

7. The method according to claim 6, further comprising designating a first area of the plurality of areas as being clean when the robotic cleaning device encounters previously registered path markers when moving in any direction without being able to establish the offset to any of the registered path markers.

8. The method according to claim 7, further comprising moving from the first area to a second area to be cleaned of the plurality of areas and tracing the registered path markers of a loop defining the second area to be cleaned.

9. The method according to claim 1, wherein the path markers are registered at a side periphery of the robotic cleaning device or a cleaning opening of the robotic cleaning device, as seen in a direction of movement of the robotic cleaning device.

10. The method according to claim 9, wherein tracing the registered path markers comprises tracing the registered path markers with a side periphery of the robotic cleaning device or the cleaning opening of the robotic cleaning device, as seen in a direction of movement of the robotic cleaning device.

11. The method according to claim 9, wherein the robotic cleaning follows the boundary of the first object or the edge of the second object so that the path markers are registered on the side periphery of the robotic cleaning device or the cleaning opening of the robotic cleaning device that is located away from the boundary or the edge.

12. The method according to claim 1, wherein the registering of path markers is started when a corner of the first object is detected.

13. A robotic cleaning device comprising:

a main body;

a propulsion system arranged to move the robotic cleaning device;

a contact detecting portion connected to the main body and arranged to detect if the robotic cleaning device is in contact with an object;

a dead reckoning sensor operatively connected to the propulsion system; and

a processing unit arranged to control the propulsion system;

wherein the processing unit is connected to the dead reckoning sensor and configured to;

follow a boundary of a first object while registering path markers at intervals on the surface, the registered path markers are virtual markers stored in a memory device of the robotic cleaning device, the virtual markers including positional data indicating respective positions of the robotic cleaning device detected by the dead reckoning sensor;

trace the registered path markers at an offset upon encountering one or more of the registered path markers; and

switch from tracing the registered path markers to following an edge of a second object upon detection of the second object.

14. A computer program comprising computer-executable instructions stored in a non-transitory medium for causing a robotic cleaning device to:

follow a boundary of a first object while registering path markers at intervals on the surface, the registered path markers are virtual markers stored in a memory device of the robotic cleaning device, the virtual markers including positional data indicating respective positions of the robotic cleaning device detected by a sensor;

trace the registered path markers at an offset upon encountering one or more of the registered path markers; and

switch from tracing the registered path markers to following an edge of a second object upon detection of the second object.

15. The computer program of claim 14, wherein the computer-executable functions are executed on a processing unit in the robotic cleaning device.