System and method for autonomous mopping of a floor surface

• US 8,892,251 B1
• Filed: 12/23/2010
• Issued: 11/18/2014
• Est. Priority Date: 01/06/2010
• Status: Active Grant

• Current Assignee: iRobot Corporation
• Original Assignee: iRobot Corporation
• Inventors: Dooley, Michael, Case, James Philip, Romanov, Nikolai
• Primary Examiner(s): Jen, Ian
• Application Number:
  US12/928,965
• Time in Patent Office: 1,426 Days
• Field of Search: 700/245
• US Class Current: 700/245
• CPC Class Codes: A47L 11/30 by suction
• 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 11/4036 Parts or details of the surface treating tools
• 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 11/4066 Propulsion of the whole machine
• CPC Class Codes: A47L 11/4088 Supply pumps; Spraying devices; Supply conduits
• CPC Class Codes: A47L 2201/04 Automatic control of the travelling movement; Automatic obstacle detection
• CPC Class Codes: B25J 11/0085 Cleaning
• CPC Class Codes: G05B 2219/39219 Trajectory tracking
• CPC Class Codes: G05D 1/021 specially adapted to land vehicles
• CPC Class Codes: G05D 1/0212 with means for defining a desired trajectory involving a plurality of land vehicles G05D1/0287
• CPC Class Codes: G05D 1/0219 ensuring the processing of the whole working surface

Abstract

A mobile robot configured to travel across a residential floor or other surface while cleaning the surface with a cleaning pad and cleaning solvent is disclosed. The robot includes a controller for managing the movement of the robot as well as the treatment of the surface with a cleaning solvent. The movement of the robot can be characterized by a class of trajectories that achieve effective cleaning. The trajectories include sequences of steps that are repeated, the sequences including forward and backward motion and optional left and right motion along arcuate paths.

Claims

1. A mobile robot configured to clean a space, the robot comprising:

a cleaning assembly;

a module configured to cause, at least in part, the robot to follow a cleaning trajectory comprising a sequence of paths repeated a plurality times; and

a drive system configured to move the robot in accordance with the cleaning trajectory;

wherein said sequence of paths that the module is configured to cause the robot to follow comprises;

a first path, wherein the robot is moved forward a first distance and to the left;

a second path, wherein the robot is moved backward and a third distance to the right;

a third path, wherein the robot is moved forward a second distance and to the right; and

a fourth path, wherein the robot is moved backward and a fourth distance to the left;

wherein the first path and third path are characterized by a first distance forward, and the second path and fourth path are characterized by a second distance backward, wherein the first distance is greater than the second distance;

wherein the third distance is substantially equal to the fourth distance.

2. The mobile robot of claim 1, wherein the first path is a first arcuate path, the second path is second arcuate path, the third path is a third arcuate path, and the fourth path is a fourth arcuate path.

3. The mobile robot of claim 2, wherein the first distance forward is double the second distance backward.

4. The mobile robot of claim 3, wherein the first distance forward is no more than double a width of the clearing assembly.

5. The mobile robot of claim 2, wherein the third distance to the right and fourth distance to the left are less than a width of the cleaning assembly.

6. The mobile robot of claim 1, wherein an elapse time of said sequence is greater than 5 seconds and less than 60 seconds.

7. The mobile robot of claim 1, further comprising:

a navigation module configured to determine a position and orientation of the robot;

a module configured to guide the robot over a floor of a room until each traversable section of the floor has been traversed.

8. The mobile robot of claim 1, wherein the cleaning assembly is configured to detachably attach a cleaning sheet.

9. The mobile robot of claim 8, wherein the cleaning sheet is a wet sheet impregnated with a cleaning solution.

10. The mobile robot of claim 2, wherein the sequence consists of arcuate paths, and the robot further comprises:

a gyro configured to detect rotation of the robot; and

a module configured to detect slippage of drive system wheels based on the rotation detected by the gyro.

11. The mobile robot of claim 8, further comprising a cleaning solution dispenser configured to dispense cleaning solution from the robot for cleaning a floor in conjunction with the cleaning sheet.