Autonomous Surface Cleaning Robot

Abstract

A mobile floor cleaning robot includes a body defining a forward drive direction, a drive system, a cleaning system, and a controller. The cleaning system includes a pad holder, a reservoir, a sprayer, and a cleaning system. The pad holder has a bottom surface for receiving a cleaning pad. The reservoir holds a volume of fluid, and the sprayer sprays the fluid forward the pad holder. The controller is in communication with the drive and cleaning systems. The controller executes a cleaning routine that includes driving in the forward direction a first distance to a first location, then driving in a reverse drive direction a second distance to a second location. From the second location, the robot sprays fluid in the forward drive direction but rearward the first location. The robot then drives in alternating forward and reverse drive directions while smearing the cleaning pad along the floor surface.

What is claimed is: 
     
         1 . A mobile floor cleaning robot comprising:
 a robot body defining a forward drive direction;   a drive system supporting the robot body to maneuver the robot across a surface the drive system comprising right and left drive wheels disposed on corresponding right and left portions of the robot body; and   a cleaning assembly disposed on the robot body, the cleaning assembly comprising:
 a pad holder disposed forward of the drive wheels and having a top portion and a bottom portion, the bottom portion having a bottom surface arranged within between about ½ cm and about 1½ cm of the surface and configured to receive a cleaning pad, the bottom surface of the pad holder comprising at least 40% of a surface area of a footprint of the robot; and 
 an orbital oscillator having less than 1 cm of orbital range disposed on the top portion of the pad holder; 
   wherein the pad holder is configured to permit more than 80 percent of the orbital range of the orbital oscillator to be transmitted from the top of the received cleaning pad to the bottom surface of the received cleaning pad.   
     
     
         2 . The robot of  claim 1 , wherein orbital range of the orbital oscillator is less than ½ cm during at least part of a cleaning run. 
     
     
         3 . The robot of  claim 2 , wherein the drive system drives forward and backward while oscillating the cleaning pad. 
     
     
         4 . The robot of  claim 2 , wherein the drive system drives in a birdsfoot motion to move the cleaning pad forward and backward along a center trajectory, forward and backward along a trajectory to a left side of and heading away from a starting point along the center trajectory, and forward and backward along a trajectory to a right side of and heading away from a starting point along the center trajectory. 
     
     
         5 . The robot of  claim 1 , wherein the cleaning pad has a top surface attached to the bottom surface of the pad holder and the top of the pad is substantially immobile relative to the oscillating pad holder. 
     
     
         6 . The robot of  claim 1 , wherein the cleaning assembly further comprises at least one post disposed on the top portion of the pad holder, the at least one post sized for receipt by a corresponding aperture defined by the robot body. 
     
     
         7 . The robot of  claim 6 , wherein the at least one post has a cross sectional diameter varying in size along its length. 
     
     
         8 . The robot of  claim 6 , wherein the at least one post comprises a vibration dampening material. 
     
     
         9 . The robot of  claim 1 , wherein the cleaning assembly further comprises:
 a reservoir to hold a volume of fluid; and   a fluid applicator in fluid communication with the reservoir, the fluid applicator configured to apply the fluid along the forward drive direction forward of the pad holder.   
     
     
         10 . The robot of  claim 9 , wherein the cleaning pad is configured to absorb about 90% of the fluid volume held in the reservoir. 
     
     
         11 . A method of operating a mobile floor cleaning robot, the method comprising:
 driving in a forward drive direction defined by the robot a first distance to a first location while moving a cleaning pad carried by the robot along a floor surface supporting the robot, the cleaning pad having a center and lateral edges;   driving in a reverse drive direction, opposite the forward drive direction, a second distance to a second location while moving the cleaning pad along the floor surface;   from the second location, applying fluid to an area substantially equal to a footprint area of the robot on the floor surface in the forward drive direction forward of the cleaning pad but rearward of the first location; and   returning the robot to the area in a movement pattern that moves the center and lateral edges of the cleaning pad separately through the area to moisten the cleaning pad with the applied fluid.   
     
     
         12 . The method of  claim 11 , further comprising driving in a left drive direction or a right drive direction while driving through the applied fluid in the alternating forward and reverse directions after spraying fluid on the floor surface. 
     
     
         13 . The method of  claim 11 , wherein applying fluid on the floor surface comprises spraying fluid in multiple directions with respect to the forward drive direction. 
     
     
         14 . The method of  claim 11 , wherein the second distance is at least equal to a length of one footprint area of the robot. 
     
     
         15 . The method of  claim 11 , wherein the mobile floor cleaning robot comprises:
 a robot body defining the forward drive direction and having a bottom portion;   a drive system supporting the robot body and configured to maneuver the robot over the floor surface;   a pad holder disposed on the bottom portion of the robot body and configured to hold the cleaning pad; and   a fluid applicator housed by the robot body and in fluid communication with a fluid reservoir.   
     
     
         16 . The method of  claim 15 , wherein the cleaning pad disposed on a bottom portion of the pad holder absorbs about 90% of the fluid contained in the reservoir.