System and method for autonomous mopping of a floor surface
View Patent ↗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.
1. A mobile robot configured to clean a surface, the mobile robot comprising:
a bump sensor configured to detect at least walls:
a cleaning assembly having a width; and
a motion controller system that causes the mobile robot to perform, a repeated number of times, driving operations comprising:
driving the mobile robot forward along a first straight path, by oscillating the mobile robot in forward and backward directions by repeatedly:
driving the mobile robot forward a first distance along the first straight path;
driving the mobile robot backward a second distance along the first straight path, the second distance less than the first distance;
at least partly in response to detecting, by the bump sensor, a wall:
driving the mobile robot in a 180 degree rotation while driving the mobile robot to a side of the first straight path by a distance approximately equal to the width of the cleaning assembly;
driving the mobile robot forward along a second straight path parallel to the first straight path, by oscillating the mobile robot in forward and backward directions by repeatedly:
driving the mobile robot forward the first distance along the second straight path;
driving the mobile robot backward the second distance along the second straight path, the second distance less than the first distance.
2. The mobile robot of claim 1 , further comprising a navigation system, comprising hardware, that tracks paths on a floor traversed by the mobile robot and causes the mobile robot to avoid areas of the floor that have already been cleaned by the mobile robot.
3. The mobile robot of claim 1 , further comprising a navigation system comprising hardware that:
determines a position and orientation of the mobile robot; and
guides the mobile robot over a floor of a room until each traversable section of the floor has been traversed.
4. The mobile robot of claim 1 , wherein the cleaning assembly is configured to detachably attach a cleaning sheet to the mobile robot.
5. The mobile robot of claim 1 , wherein the cleaning assembly is configured to detachably attach a wet cleaning sheet impregnated with a cleaning solution.
6. The mobile robot of claim 1 , further comprising a cleaning solution dispenser configured to dispense cleaning solution from the mobile robot for cleaning a floor in conjunction with a cleaning sheet attached to the cleaning assembly.
7. The mobile robot of claim 1 , further comprising a hinge connected to the cleaning assembly wherein the hinge is configured to enable the cleaning assembly to:
pivot forward when the mobile robot is driven forward to press a front portion of a cleaning pad attached to the cleaning assembly against a floor while lifting a back portion of the cleaning pad away from the floor; and
pivot backward when the mobile robot is driven backward to press the back portion of the cleaning pad against the floor while lifting the forward portion of the cleaning pad away from the floor.
8. The mobile robot of claim 1 , further comprising:
a detection device that detects rotation of the mobile robot; and
a navigation module comprising hardware that detects slippage of drive system wheels based on the rotation detected by the detection device, and based on the detected slippage provides path correction.
9. The mobile robot of claim 1 , further comprising:
a gyroscope;
an odometer;
an optical sensor configured to detect light reflected from a ceiling;
a navigation system comprising hardware that determines position and orientation of the mobile robot using readings from the gyroscope, the odometer, and the optical sensor.
10. A method of cleaning a space with a mobile robot having a cleaning assembly, the method comprising:
driving, by a motion controller system, the mobile robot forward along a first straight path, by oscillating the mobile robot in forward and backward directions by repeatedly:
driving the mobile robot forward a first distance along the first straight path;
driving the mobile robot backward a second distance along the first straight path, the second distance less than the first distance;
at least partly in response to detecting, by a bump sensor, a wall:
driving, by the motion controller system, the mobile robot in a 180 degree rotation and driving the mobile robot to a side of the first straight path by a distance approximately equal to a width of the cleaning assembly;
driving the mobile robot forward along a second straight path parallel to the first straight path, by oscillating the mobile robot in forward and backward directions by repeatedly:
driving the mobile robot forward the first distance along the second straight path;
driving the mobile robot backward the second distance along the second straight path, the second distance less than the first distance.
11. The method as defined in claim 10 , the method further comprising tracking paths on a floor traversed by the mobile robot and causing the mobile robot to avoid areas of the floor that have already been cleaned by the mobile robot.
12. The method as defined in claim 10 , the method further comprising:
determining a position and orientation of the mobile robot; and
guiding the mobile robot over a floor of a room until each traversable section of the floor has been traversed.
13. The method as defined in claim 10 , the method further comprising enabling a cleaning sheet to be detachably attached to the cleaning assembly.
14. The method as defined in claim 10 , the method further comprising enabling a wet cleaning sheet impregnated with a cleaning solution to be detachably attached to the cleaning assembly.
15. The method as defined in claim 10 , the method further comprising dispensing, by a cleaning solution dispenser, cleaning solution from the mobile robot, onto a floor being traversed by the mobile robot.
16. The method as defined in claim 10 , the method further comprising:
pivoting the cleaning assembly forward when the mobile robot is driven forward to press a front portion of a cleaning pad attached to the cleaning assembly against a floor while lifting a back portion of the cleaning pad away from the floor; and
pivoting the cleaning assembly backward when the mobile robot is driven backward to press the back portion of the cleaning pad against the floor while lifting the forward portion of the cleaning pad away from the floor.
17. The method as defined in claim 10 , the method further comprising:
detecting slippage of drive system wheels; and
based on the detected slippage, providing path correction.
18. The method as defined in claim 10 , the method further comprising determining position and orientation of the mobile robot using readings from a gyroscope, an odometer, and an optical sensor configured to detect light reflected from ceiling.