Cleaning the cleaning pad

Abstract

A cleaning station for a mobile robot includes a fluid container and a roller disposed within the fluid container. The fluid container is configured to hold a cleaning fluid that at least partially immerses the roller. The cleaning station includes a control system configured to rotate the roller when the mobile robot docks with the cleaning station to direct the cleaning fluid from the fluid container onto a cleaning pad of the mobile robot and remove debris from the cleaning pad.

Description

[Technical Field]

[0001] FIELD OF THE DISCLOSURE The present disclosure relates generally to cleaning cleaning pads of mobile cleaning robots. [Background technology]

[0002] Cleaning robots include mobile robots that autonomously perform cleaning tasks within a home or other environment. Some cleaning robots are equipped with cleaning pads that collect debris. Cleaning robots can travel to a docking station to charge the cleaning robot or to empty debris from the cleaning robot. Summary of the Invention

[0003] The cleaning robot may be equipped with a cleaning pad that scrubs the floor surface to pick up debris, such as during a mopping operation. The debris becomes trapped in the cleaning pad, which can be removed for reuse. To clean the cleaning pad and remove debris, the cleaning robot and cleaning station may interact with each other in a pad cleaning routine. During the pad cleaning routine, the cleaning robot docks with the cleaning station, and rollers in the cleaning station interact with the robot's cleaning pad. The cleaning station rollers draw cleaning fluid from a fluid container and force the cleaning fluid through the robot's cleaning pad, hydraulically removing trapped debris in conjunction with mechanical agitation. In some cases, moving the cleaning pad and roller relative to each other can facilitate debris removal.

[0004] In some aspects, the present disclosure describes a cleaning station for a mobile robot. The cleaning station includes a housing, a fluid reservoir mounted within the housing, and a roller disposed within the fluid reservoir. The fluid reservoir is configured to hold a cleaning fluid that at least partially immerses the roller. The cleaning station includes a control system configured to rotate the roller to direct the cleaning fluid from the fluid reservoir to a cleaning pad of the mobile robot and remove debris from the cleaning pad when the mobile robot docks with the cleaning station.

[0005] In some aspects, the present disclosure describes a cleaning station for a mobile robot. The cleaning station includes a fluid reservoir and a roller disposed within the fluid reservoir. The fluid reservoir is configured to hold a cleaning fluid that at least partially immerses the roller. The cleaning station includes a control system configured to rotate the roller to direct the cleaning fluid from the fluid reservoir to a cleaning pad of the mobile robot and remove debris from the cleaning pad when the mobile robot docks with the cleaning station.

[0006] These and other described cleaning stations may have at least one or more of the following characteristics:

[0007] In some embodiments, the roller is translatable relative to the mobile robot during rotation of the roller.

[0008] In some embodiments, the cleaning station includes a translation mechanism attached to the fluid container, the translation mechanism operable to translate the roller relative to the mobile robot during rotation of the roller.

[0009] In some embodiments, the cleaning station includes a docking surface for receiving a mobile robot, the fluid container being disposed in a recess in the docking surface.

[0010] In some embodiments, the rollers are positioned to contact the cleaning pad, and the docking surface has a length that allows the mobile robot to move through the extent of the cleaning pad when the mobile robot is docked at the cleaning station with the rollers in contact with the cleaning pad.

[0011] In some embodiments, the control system is configured to rotate the roller so that a portion of the roller near the cleaning pad moves in a direction opposite to the direction of relative translation between the roller and the cleaning pad.

[0012] In some embodiments, the roller includes at least one of one or more fletches extending along the length of the surface of the roller, one or more protrusions projecting from the surface of the roller, or one or more lobes smoothly distorting the surface of the roller.

[0013] In some embodiments, the roller comprises an elastomer.

[0014] In some embodiments, the roller is positioned to contact the cleaning pad when the mobile robot is docked at the cleaning station.

[0015] In some embodiments, the cleaning station includes a spring-loaded mount to which the roller is attached, the spring-loaded mount configured to urge the roller against the cleaning pad.

[0016] In some embodiments, rotation of the roller directs the cleaning fluid onto the cleaning pad and back into the fluid reservoir.

[0017] In some embodiments, the cleaning station includes a conduit fluidly coupled to the fluid container, and during a cleaning cycle, the control system is configured to cause cleaning fluid to flow into the fluid container and, after the cleaning fluid has been forced into the cleaning pad, to expel the cleaning fluid from the fluid container via the conduit.

[0018] In some embodiments, the cleaning station includes a vacuum source configured to apply a vacuum to draw cleaning fluid from the fluid container.

[0019] In some embodiments, when the control system withdraws the cleaning fluid, the vacuum source creates a negative pressure of between 5 kPa and 30 kPa on the fluid container.

[0020] In some embodiments, the cleaning fluid is expelled through the conduit at a velocity between 0.5 m / s and 4.0 m / s.

[0021] In some embodiments, the cleaning station includes a septum disposed within the conduit, the septum having dimensions that limit the size of debris flowing through the conduit.

[0022] In some embodiments, the cleaning station includes a sensor disposed within the fluid container and communicatively coupled to a control system configured to measure a contamination level of cleaning fluid within the fluid container, and the control system configured to drain the cleaning fluid from the fluid container when the contamination level exceeds a threshold.

[0023] In some embodiments, the control system is configured to repeat the cleaning cycle until the cleaning cycle has been cycled a threshold number of times or a threshold amount of cleaning fluid has passed through the cleaning pad, where the threshold number of cycles or threshold amount of cleaning fluid is based on at least one of the duration of cleaning performed by the mobile robot, the area of the environment cleaned by the mobile robot, the type of cleaning performed by the mobile robot, the time a floor area has not been cleaned by the mobile robot, the level of soiling detected by the mobile robot, the type of room cleaned by the mobile robot, the current season, or current or past weather.

[0024] In some embodiments, the cleaning station includes a sensor disposed within the fluid container and communicatively coupled to the control system, the sensor configured to measure a contamination level of the cleaning fluid within the fluid container, and the control system configured to repeat the cleaning cycle until the contamination level falls below a threshold at a predetermined time during the cleaning cycle.

[0025] In some embodiments, the control system is configured to allow cleaning fluid to flow into the fluid container until between 15% and 50% of the height of the roller is submerged in the cleaning fluid.

[0026] In some embodiments, the cleaning station includes a waste tank fluidly coupled to a fluid container, a dry debris canister, a vacuum source, and a valve. In a first configuration of the valve, the valve fluidly couples the vacuum source to the waste tank, such that a vacuum applied by the vacuum source draws cleaning fluid from the fluid container into the waste tank. In a second configuration of the valve, the valve fluidly couples the vacuum source to the dry debris canister, such that a vacuum applied by the vacuum source draws dry debris contained within the mobile robot into the dry debris canister.

[0027] In some embodiments, the cleaning station includes a waste tank, a vacuum source, and a valve. In a first configuration of the valve, the valve fluidly couples the waste tank to the fluid container, and a vacuum applied by the vacuum source draws cleaning fluid from the fluid container into the waste tank. In a second configuration of the valve, the valve fluidly couples the vacuum source to an exhaust port of the mobile robot, and a vacuum applied by the vacuum source draws dry debris stored within the mobile robot into the waste tank.

[0028] In some embodiments, the cleaning station includes a waste tank fluidly coupled to the fluid container, a solid waste canister fluidly coupled to the fluid container, a vacuum source, and a filter positioned to receive the mixture of debris and cleaning fluid from the fluid container and direct the debris to the solid waste canister and the cleaning fluid to the waste tank.

[0029] In some embodiments, the roller is a first roller and the cleaning station includes a second roller disposed within the fluid reservoir or disposed within a second fluid reservoir of the cleaning station.

[0030] Some aspects of the present disclosure describe a mobile cleaning robot that includes a drive system for maneuvering the mobile cleaning robot within an environment during a cleaning mission, a pad holder for receiving a fabric pad for removing and capturing debris from a floor surface, and a control system configured to dock the mobile cleaning robot to a docking station for cleaning the fabric pad in a pad cleaning routine and to move the fabric pad relative to the docking station during the pad cleaning routine.

[0031] This and other described mobile cleaning robots may have at least one or more of the following characteristics:

[0032] In some embodiments, the mobile cleaning robot includes a movement mechanism attached to the pad holder, the movement mechanism operable to move the fabric pad relative to the docking station.

[0033] In some embodiments, moving the fabric pad relative to the docking station includes causing a drive system to maneuver the mobile cleaning robot relative to the docking station.

[0034] In some embodiments, moving the fabric pad relative to the docking station includes moving the fabric pad relative to the docking station in response to receiving a command from the docking station.

[0035] In some embodiments of the present disclosure, a system is described. The system includes a cleaning station including a roller and a mobile robot including a pad holder that receives a fabric pad for removing and capturing debris from a floor surface. The roller is positioned to contact the fabric pad when the mobile robot is docked with the cleaning station for a pad cleaning routine. At least one of the cleaning station or the mobile robot is configured to cause relative movement between the fabric pad and the roller during the pad cleaning routine. One or more components of the system may have one or more of the characteristics described for the cleaning station and mobile cleaning robot above.

[0036] These and other features of the cleaning station and cleaning robot provide one or more benefits. Combining hydraulic cleaning with agitation of the cleaning pad with a roller can remove debris more effectively than some cleaning methods. For example, small debris is more likely to be dislodged from the cleaning pad fibers, increasing the overall percentage of debris removed. Combining roller action with relative movement of the cleaning pad and roller can further enhance debris removal. Additionally, pad cleaning with a roller in a fluid container can effectively limit the spread of cleaning fluid (including dirty fluid) and debris on the cleaning station, facilitating or eliminating manual cleaning. Overall cleaning fluid usage can be reduced, improving the user experience.

[0037] The details of one or more embodiments are set forth in the accompanying drawings and description. Other features, objects, and advantages will become apparent from the description, drawings, and claims. [Brief explanation of the drawings]

[0038] [Figure 1A] 10A and 10B illustrate an example of a mobile cleaning robot docking at a cleaning station. [Figure 1B]FIG. 2 illustrates components of an example cleaning station. [Figure 2A] FIG. 1 is an exploded view illustrating an example of a fluid container assembly. [Figure 2B] FIG. 1 is a side view illustrating an example of a fluid container assembly. [Figure 3A] FIG. 10 is a diagram illustrating an example of a cleaning cycle. [Figure 3B] FIG. 10 is a diagram illustrating an example of a cleaning cycle. [Figure 3C] FIG. 10 is a diagram illustrating an example of a cleaning cycle. [Figure 3D] FIG. 10 is a diagram illustrating an example of a cleaning cycle. [Figure 4A] FIG. 1 is a perspective view of an example roller. [Figure 4B] FIG. 1 is a perspective view of an example roller. [Figure 4C] FIG. 1 is a perspective view of an example roller. [Figure 5] 10A and 10B illustrate an example of a mobile cleaning robot docking at a cleaning station. [Figure 6A] 10A and 10B are diagrams illustrating an example of a cleaning robot moving relative to a cleaning station. [Figure 6B] 10A and 10B are diagrams illustrating an example of a cleaning robot moving relative to a cleaning station. [Figure 7A] 10A-10C illustrate an example of a fluid container assembly that moves relative to a cleaning pad. [Figure 7B] 10A-10C illustrate an example of a fluid container assembly that moves relative to a cleaning pad. [Figure 8A] 10A and 10B illustrate an example of movement of the cleaning pad relative to the cleaning station. [Figure 8B] 10A and 10B illustrate an example of movement of the cleaning pad relative to the cleaning station. [Figure 9] 10A-10C show examples of containers for cleaning stations. [Figure 10] 1 is a perspective view of an example of a shielding element. [Figure 11] FIG. 1 illustrates an example of a cleaning station including two fluid container assemblies. [Figure 12] FIG. 10 shows an example of a cleaning station with two rollers within a fluid container. [Figure 13] FIG. 1 illustrates the transfer of waste to a waste tank and dry debris canister. [Figure 14] FIG. 1 illustrates the transfer of waste to a common waste tank. [Figure 15] FIG. 1 illustrates an example of solid and liquid waste separation. [Figure 16] 1A and 1B illustrate examples of air and liquid separation. [Figure 17] FIG. 1 illustrates components of an example cleaning robot.

[0039] Like reference symbols in the various drawings indicate like elements. DETAILED DESCRIPTION OF THE INVENTION

[0040] Described herein are methods for cleaning a cleaning pad of a cleaning robot. As a cleaning robot, such as a mobile cleaning robot, moves through an environment, the robot carries a cleaning pad that contacts a floor surface and collects debris. When the robot docks with a cleaning station, the cleaning station operates to remove the debris, allowing the cleaning pad to be reused. According to some embodiments of the present disclosure, the cleaning station includes a fluid container and a roller within the fluid container. The roller is at least partially immersed in a cleaning fluid held in the fluid container, and rotation of the roller forces the cleaning fluid onto and through the cleaning pad of the docked robot. The hydraulic force of the cleaning fluid, combined with physical agitation of the cleaning pad, forces debris from the cleaning pad into the fluid container, allowing the cleaning pad to be reused. In some embodiments, the roller, robot, and / or cleaning pad can move during cleaning, improving cleaning effectiveness.

[0041] As shown in FIG. 1 , the system 100 includes a cleaning station 102 and a cleaning robot 122. The robot 122 includes a pad holder 126 that holds a cleaning pad 124, such as a fabric pad. During a cleaning mission, such as a dry cleaning mission (e.g., dusting or sweeping) or a wet cleaning mission (e.g., mopping), the robot 122 moves along a floor surface and floor debris is collected on the cleaning pad 124. After one or more cleaning missions and / or during a cleaning mission, the robot 122 returns to and docks at the cleaning station 102. For example, the robot 122 may return to the cleaning station 102 upon completion of a cleaning mission, upon completion of a predetermined portion of a cleaning mission, upon completion of a predetermined number of cleaning missions, upon cleaning for a predetermined period of time during or across multiple cleaning missions, in response to a command sent to the robot 122 by a user device or the cleaning station 102, in response to the robot's 122 battery level dropping below a threshold, in response to the robot's debris level exceeding a threshold, or based on another reason.

[0042] When the robot 122 docks with the cleaning station 102, the components of the cleaning station 102 operate to clean the cleaning pad 124. Examples of the components of the cleaning station 102 are shown in FIGS. 1A and 1B, and in various embodiments, the cleaning station may include some or all of these components in various combinations. The components of the cleaning station 102 may be mounted to an overall cleaning station housing 120, which may include one or more portions to provide structural support to the components and maintain the components in their respective positions. In some embodiments, the housing 120 may support docking of the robot 122 on the housing 120 (e.g., to a ramp or other docking surface on the housing 120).

[0043] In some embodiments, the cleaning station 102 includes a control system 104, such as a computer system. The control system 104 is configured to obtain sensor readings from the control system's sensors 128, read data from one or more other components of the cleaning station 102, and send data (e.g., commands) to operate the components of the cleaning station 102, as described with reference to various examples below. In some embodiments, the control system 104 is configured to communicate with the robot 122, for example, using a communication system 134. For example, the control system 104 may be configured to send commands to the robot 122 to cause the robot 122 to dock with the cleaning station 102, or to send commands to the robot 122 to cause the robot 122 to begin or end operations related to pad cleaning (e.g., move the robot 122 relative to the rollers of the cleaning station 102 and / or move the cleaning pad 124 relative to the rollers, and / or receive data from the robot 122, e.g., indicating that the robot 122 should begin docking or indicating a direction of movement of the cleaning pad 124 attached to the robot 122). In some embodiments, the control system 104 is configured to communicate with a user device, such as a mobile phone, tablet, or computer, using the communication system 134. For example, the control system 104 may receive commands from the user device to cause the cleaning station 102 to perform a pad cleaning or to change one or more parameters of the pad cleaning. As another example, the control system 104 may send data to a user device that causes the user device to display the current status of the pad cleaning (such as the measured level of debris and an indication that the pad cleaning is complete).

[0044] The control system 104 is configured to control the components of the cleaning station 102 to perform pad cleaning. For example, the control system 104 may provide signals to the motor 132 to cause the motor 132 to rotate a roller in a particular direction, provide signals to the movement mechanism 130 or a motor coupled to the movement mechanism 130, and / or provide signals to the flow control system 112 (e.g., a blower, pump, and / or valves of the flow control system 112) to force cleaning fluid into the fluid container, evacuate cleaning fluid and waste from the fluid container, and / or draw dry debris from the cleaning robot into the dry debris canister 106, and move the fluid container assembly 114 (or a portion thereof) relative to the cleaning robot.

[0045] 2A and 2B, includes one or more rollers and one or more fluid reservoirs that hold cleaning fluid, which is drawn from the reservoir and expels debris into the reservoir via the cleaning pad 124. The cleaning fluid and debris are then expelled from the reservoir.

[0046] The cleaning station 102 may include one or more tanks / canisters. The cleaning fluid tank 108 stores unused cleaning fluid, which may be dispensed into the fluid container of the fluid container assembly 114 and used to clean the cleaning pad. The dry debris canister 106 collects dry debris expelled from the robot, e.g., vacuumed by the robot. The waste tank 110 holds used cleaning fluid (e.g., cleaning fluid contaminated with debris) after it has passed through the cleaning pad 124 and been expelled from the fluid container. In some embodiments, the waste tank 110 holds at least some solid debris removed from the cleaning pad 124 and expelled with the used cleaning fluid. In some embodiments, the dry debris canister 106 and the waste tank 110 are combined into a common waste tank that holds both solid debris and dirty cleaning fluid, as described with reference to FIG. 14 .

[0047] The flow control system 112 includes components for transporting cleaning fluid and debris between components of the cleaning station 102. For example, the flow control system 112 can include one or more vacuum or pressure sources, such as pumps or blowers, to generate the flow of cleaning fluid and debris. In some embodiments, the flow control system 112 includes one or more valves (e.g., adjustable valves) that can be switched (e.g., by the control system 104) between multiple configurations to change the flow rate and / or flow path of the cleaning fluid and / or debris. The flow control system 112 includes pipes, tubes, and / or other conduits 118, as shown in FIG. 1A , configured to transport the cleaning fluid and debris as guided by the vacuum and / or pressure sources. For example, in some embodiments, the conduit 118 fluidly couples the cleaning fluid tank 108 to a fluid container to transport the cleaning fluid to the fluid container. In some embodiments, a conduit 118 fluidly couples the fluid container to the waste tank 110 and transports used cleaning fluid and / or debris to the waste tank 110. In some embodiments, a conduit 118 fluidly couples the inlet port 116 to the dry debris canister 106 or the waste tank 110 and transports solid debris from the inlet port 116 to the dry debris canister 106 or the waste tank 110. The conduit 118 connections shown in FIG. 1A are merely exemplary, and other configurations for transporting cleaning fluid and debris between components, as described herein, are within the scope of the present disclosure.

[0048] In some embodiments, the cleaning station 102 includes an intake port 116. As described in more detail with respect to Figures 5 and 13-14, the intake port 116 is configured to interface with an exhaust port of the robot 122 to receive dry debris from the robot 122. The dry debris is then transported to the dry debris canister 106 or waste tank 110 for storage and eventual removal.

[0049] In some embodiments, the cleaning station 102 includes one or more sensors 128. As described in more detail in FIGS. 3A-3D , in some embodiments, the sensor 128 includes a sensor configured to measure the contamination level of the cleaning fluid in the fluid container. In some embodiments, the sensor 128 includes a sensor configured to detect whether the robot 122 is docked to the cleaning station 102. In some embodiments, the sensor 128 includes one or more sensors for detecting the fill level of one or more of the tanks / canisters 106, 108, 110. In some embodiments, the sensor 128 includes one or more sensors for detecting large debris, for example, based on measuring the rotation of rollers. The output of the sensor 128 (e.g., an electrical signal or digital data) is transmitted to the control system 104, which may be configured to perform an action in response to the sensor output.

[0050] 6A-8B, the cleaning station 102 includes a movement mechanism 130. The movement mechanism 130 may move all or part of the fluid container assembly 114 relative to the robot 122 during cleaning of the cleaning pad 124, thereby increasing the effectiveness of the cleaning.

[0051] In some embodiments, the cleaning station 102 includes a motor 132 that drives the rotation of the rollers of the fluid container assembly 114. For example, the motor 132 is an AC brushless motor, a DC brushed or brushless motor, a direct drive motor, or a rotary servo motor.

[0052] In some embodiments, the cleaning station 102 includes a communication system 134 configured to transmit and receive signals to and from one or more other devices such as a cleaning robot, a user device, and / or a remote computer system (such as a cloud computer system). For example, the communication system 134 can transmit and receive wireless signals such as short-range signals (such as Bluetooth), medium-range signals (such as Wi-Fi), and / or cellular network signals.

[0053] The cleaning station need not include all of the components shown in FIG. 1B. Further, in some embodiments, additional components / functions are included in the cleaning station. For example, in some embodiments, the cleaning station includes a charging component for charging the cleaning robot 122 when the cleaning robot 122 is docked to the cleaning station.

[0054] As shown in FIG. 2A, an example of the fluid container assembly 114 includes rollers 200 and a fluid container 202. The fluid container 202 is sized and shaped to accommodate the rollers 200 and has, for example, an open curved cross-section (such as an open semi-circle) or an open rectangular cross-section, which is defined by the side walls 218 of the fluid container 202. The side walls 218 at least partially define a reservoir 250 that (i) receives and holds the cleaning liquid 220 and (ii) receives at least a portion of the rollers 200. The fluid container 202 is provided with at least one orifice 204, and the at least one orifice 204 is connected to at least one conduit 208 that fluidly couples the fluid container 202 to one or more components of the cleaning station 102. The fluid container 202 may be constructed of a suitable material such as a plastic that is resistant to the cleaning liquid.

[0055] 2A and 2B, roller 200 is an elongated body rotatable about central axis 201, sized and shaped to fit at least partially within fluid container 202. In some embodiments, roller 200 and fluid container 202 are sized and shaped such that when roller 200 is mounted in a position to rotate within fluid container 202, at least a portion of roller 200 is disposed within fluid container 202 (so that fluid returns into fluid container 202 during operation) and at least a portion of roller 200 is exposed above a cross-sectional area of fluid container 202 (so that it can contact a cleaning pad without being obstructed by fluid container 202). For example, as shown in FIG. 2B, roller 200 has a diameter 222, a portion 224 of which (e.g., 10% to 50% of diameter 222) is exposed above fluid container 202.

[0056] As shown in FIG. 2B , roller 200 has a substantially tubular shape. The tubular body 212 of roller 200 has a circular cross-section. In some embodiments, roller 200 includes surface features, such as fletches 216, that may protrude from tubular body 212. Such features may increase agitation of the cleaning pad and / or increase the amount of cleaning fluid forced into the cleaning pad by roller 200, improving debris removal, as described in more detail with reference to FIGS. 4A-4C . In some embodiments, roller 200 has a length between 7 cm and 35 cm. Roller 200 may be rigid (e.g., constructed of a rigid plastic) and / or flexible (e.g., constructed of an elastomeric material).

[0057] To rotate the tubular body 212, the roller 200 includes a shaft 210 attached to a bearing 206 that is attached to a bearing holder 214 and rotates due to torque applied by a motor (such as motor 132) of the cleaning station. In some embodiments, the fluid container 202 includes a notch 232 at one or both axial ends of the fluid container 202. One or more components associated with torque transmission to the roller 200, such as the bearing 206, may be positioned to pass through the notch 232 to facilitate torque transmission from a motor that may be located outside the fluid container 202. In some embodiments, as shown in the example of FIG. 2A , a fixed mounting portion 234 receives the end of the shaft 210 opposite the end at which torque is transmitted to the shaft 210 (the end having the bearing 206). In some embodiments, the fluid container 202 includes a holder 230 for receiving the fixed mounting portion 234.

[0058] As shown in FIG. 2B , cleaning liquid 220 can be supplied into fluid container 202 (e.g., through orifice 204 or through one or more separate inlet orifices) to at least partially immerse roller 200. Orifice 204 is located at the bottom of fluid container 202, which facilitates removal of debris from fluid container 202 that may collect at the bottom, as described in more detail below. In some embodiments, as shown in FIG. 2B , conduit 208 is shaped to reach level 236 of cleaning liquid 220 supplied to fluid container 202 during each cleaning cycle within a relatively short distance from orifice 204. This can reduce the amount of cleaning liquid 220 in conduit 208 but outside fluid container 202 during pad cleaning, as cleaning liquid in conduit 208 also reaches level 236, potentially resulting in wasted cleaning liquid that does not substantially contribute to cleaning. For example, the conduit 208 can reach the liquid level 236 within 6 cm, 5 cm, 4 cm, or 3 cm of the conduit length from the orifice 204 .

[0059] In some embodiments, the roller 200 and the fluid container 202 each have a shape and size that increases the amount of cleaning fluid expelled onto the cleaning pad and / or the velocity at which cleaning fluid is expelled onto the cleaning pad. For example, a shorter distance between the roller 200 and the sidewall 218 for at least a portion of the sidewall 218 may increase the amount of cleaning fluid moved by the rotation of the roller 200 and / or increase the velocity at which cleaning fluid is moved. In some embodiments, the minimum distance 240 between the roller 200 and the sidewall 218 is between 1 mm and 10 mm. In some embodiments, the sidewall 218 is shaped to generally follow the curve of the roller 200, e.g., the distance between the sidewall 218 and the roller 200 is maintained less than 10 mm over an angular range of between 45° and 120° or between 60° and 120° relative to the central axis 201 of the roller 200. In some embodiments, the sidewalls 218 are shaped to flare outward relative to the roller 200 near the opening of the fluid container 202 where a portion of the roller 200 is exposed. For example, as shown in FIG. 2B , the distance between the roller 200 and the sidewalls 218 increases near the top 242 of the fluid container 202 compared to sides of the fluid container 202 away from the top 242. In some embodiments, this feature (which may be included on one or both sides of the fluid container 202) increases the amount of cleaning fluid that is forced into the cleaning pad and then returned to the fluid container 202, improving the cleanliness of the cleaning station.

[0060] 3A-3D illustrate an example of a cleaning cycle for cleaning a cleaning pad, according to some embodiments of the present disclosure. As shown in FIG. 3A, cleaning solution 220 is supplied to fluid reservoir 202 (301). In some embodiments, as shown in FIG. 3A, cleaning solution 220 is supplied to fluid reservoir 202 through one or more inlet conduits (not shown) separate from conduit 208 through which cleaning solution 220 is subsequently discharged. For example, cleaning solution 220 may be supplied through two inlet conduits at opposite ends of fluid reservoir 202, e.g., opposite conduit 208. The inlet conduits may supply cleaning solution through corresponding inlet orifices (not shown) in fluid reservoir 202 and / or may supply cleaning solution into the fluid reservoir from above. In some embodiments, cleaning solution 220 is supplied to fluid reservoir 202 through conduit 208. Using separate conduits for the introduction and discharge of cleaning fluid facilitates the removal of debris from fluid container 202 as the newly introduced cleaning fluid flushes any remaining sediment toward conduit 208.

[0061] For example, in some embodiments, the control system 104 operates one or more pumps, blowers, and / or valves of the flow control system 112 to drive and / or direct the cleaning solution 220 from the cleaning solution tank 108 through one or more inlet conduits. In some embodiments, the control system 104 causes a predetermined amount of the cleaning solution 220 to enter the fluid reservoir 202, for example, by controlling the duration of the flow from the cleaning solution tank 108 to the fluid reservoir 202. In some embodiments, the cleaning solution 220 is supplied into the fluid reservoir 202 such that a portion 310 (e.g., between 15% and 50%) of the diameter or other height of the roller 200 is submerged in the cleaning solution 220.

[0062] As shown in FIG. 3B, with the cleaning solution 220 in the fluid container 202, the roller 200 rotates (306), drawing the cleaning solution 220 from the fluid container 202 onto the cleaning pad 124 and agitating the cleaning pad 124 while pushing the cleaning solution 220 onto the cleaning pad 124. For example, the control system 104 may send a signal to the motor 132 to cause the motor 132 to rotate the roller 200 in a particular direction (clockwise in this example). As shown in FIG. 3C, the flow of the cleaning solution 220 causes debris 300 trapped in the cleaning pad 124 to be released and carried into the fluid container 202 (e.g., carried by the cleaning solution 220) or to fall. The released debris 300 accumulates at the bottom 302 of the fluid container 202. The cleaning fluid 220 that passes through the cleaning pad 124 also returns to the fluid reservoir 202 (eg, facilitated by the rotation of the roller 200 ) and is either carried back to the cleaning pad 124 or drained from the fluid reservoir 202 .

[0063] A combination of one or more factors can cause debris 300 to be released from the cleaning pad 124. First, the cleaning fluid 220, forced into the cleaning pad 124 by the movement of the roller 200 (and, in some embodiments, the movement of the cleaning pad 124 and / or roller 200 relative to each other), hydraulically forces the debris 300 off the cleaning pad 124. This hydraulic force (e.g., combined with physical agitation) is effective at removing debris and, in some cases, improves debris removal. In some embodiments, hydraulic cleaning actions are more effective at removing debris than other types of cleaning, such as wetting a pad and then scrubbing it (e.g., a pad squeegee). For example, the hydraulic cleaning force is significantly lateral (e.g., in the direction 308 shown in FIG. 3B , parallel to the surface of the cleaning pad 124), which can dislodge the debris 300 rather than tightly trapping it within the cleaning pad 124, as can occur with scrubbing pads.

[0064] In addition to the benefits of the hydraulic cleaning action, in some embodiments, the cleaning liquid 220 is wicked up into the fibers of the cleaning pad 124, wetting the fibers and enhancing cleaning of the cleaning pad 124. In various embodiments, the fibers are fabric fibers and / or synthetic fibers, such as fibers attached to the body of the cleaning pad 124. Furthermore, in some embodiments, while the cleaning liquid 220 is being forced into the cleaning pad 124 (e.g., the fibers of the cleaning pad 124), the cleaning pad 124 (e.g., the fibers of the cleaning pad 124) is agitated by the roller 200. For example, the roller 200 can contact the cleaning pad 124, and the relative movement between the cleaning pad 124 and the roller 200 (e.g., rotation of the roller 200 and / or relative translation between the cleaning pad 124 and the roller 200) causes the cleaning pad 124 to vibrate. In some embodiments, the agitation is enhanced by surface features (e.g., fletches 216) of the roller 200 impacting the cleaning pad 124, as described with reference to FIGS. 4A-4C. Additionally, the agitation releases debris 300 from the cleaning pad 124. The hydraulic transmission of the cleaning fluid, the physical agitation of the fibers of the cleaning pad 124, and the wetting of the fibers work in combination to provide effective and efficient pad cleaning.

[0065] In some embodiments, during cleaning, the cleaning pad 124 and roller 200 are translated relative to one another, with the roller 200 cleaning the entire bottom surface of the cleaning pad 124 across its length (e.g., its entire length). As described in more detail with reference to FIGS. 6A-8B , the relative movement may be caused by one or more of: (i) movement of the robot relative to the cleaning station; (ii) movement of the roller 200 relative to the robot; or (iii) movement of the cleaning pad 124 relative to the cleaning station. In some embodiments, the direction of rotation of the roller 200 is controlled so that the portion of the roller 200 proximate to the cleaning pad 124 (e.g., the portion in contact with the cleaning pad 124) moves in a direction opposite to the direction of relative movement between the roller 200 and the cleaning pad 124. The direction of rotation may change with a change in the direction of translation. This relative direction of rotation may increase the effective hydraulic pressure of the cleaning solution 220 within the cleaning pad 124 and / or increase agitation of the cleaning pad 124.

[0066] As the roller 200 continues to rotate and release debris 300, in some embodiments, the cleaning solution 220 begins to become saturated with debris, thereby reducing the efficiency of cleaning. This is because the debris remains suspended in the cleaning solution 220 rather than settling to the bottom 302 of the fluid reservoir 202. Therefore, after a certain amount of cleaning has been performed, the cleaning may be stopped and the cleaning solution 220 and the debris 300 therein may be drained from the fluid reservoir 202. In some embodiments, the control system 104 determines to stop cleaning (e.g., stop rotation of the roller 200, stop relative movement of the roller 200 and cleaning pad 124, and / or drain the cleaning solution 220 from the fluid reservoir 202) based on one or more of the following: That is, the number of passes made by the roller 200 over the cleaning pad 124 (e.g., cleaning may be stopped in response to the roller 200 having traveled the length of the cleaning pad 124 a threshold number of times), the number of rotations performed by the roller 200 (e.g., cleaning may be stopped in response to the roller 200 having performed a threshold number of rotations), the amount of time cleaning has been performed (e.g., cleaning may be stopped in response to cleaning having been performed for a threshold amount of time), or sensor data indicative of the contamination level of the cleaning fluid 220 in the fluid container 202. For example, one or more sensors 304 may be disposed within the fluid container 202 (e.g., positioned to be at least partially submerged by the cleaning fluid 220 when pad cleaning occurs). The sensors 304 may include one or more types of sensors, such as a turbidity sensor that optically measures scattering of light by the cleaning fluid 220 to determine the level of contamination by debris 300 in the cleaning fluid 220. The sensors 304 may be communicatively coupled to the control system 104, for example, via a wireless or wired connection. Cleaning may be stopped in response to a contamination level exceeding a threshold contamination level, such as detected turbidity exceeding a threshold turbidity level.

[0067] 3D , one or more pumps, blowers, and / or valves of the flow control system 112 are operated (e.g., by the control system 104) to expel the cleaning fluid 220 and released debris 300 from the fluid container 202 through the conduit 208 and into the waste tank 110. For example, the pumps and / or blowers may apply a negative pressure to the fluid container 202, drawing the cleaning fluid 220 into the waste tank 110 through the conduit 208. In some embodiments, rapid movement of the cleaning fluid 220 is advantageous because it reduces the amount of debris 300 that remains in the fluid container 202 (and is not expelled with the cleaning fluid 220). For example, in some embodiments, the maximum fluid velocity of the cleaning liquid 220 in the conduit 208 during drainage is between 0.3 m / s and 8.0 m / s, e.g., between 0.5 m / s and 8.0 m / s, between 0.5 m / s and 4.0 m / s, or between 1.0 m / s and 4.0 m / s. In some embodiments, to provide high fluid velocities, the vacuum pressure causing the drainage of the cleaning liquid 220 (e.g., the vacuum pressure applied in the waste tank 110 that causes the cleaning liquid 220 to flow from the fluid container 202 to the waste tank 110, or the vacuum pressure applied in the conduit 208) is between 2 kPa and 40 kPa relative to the fluid container 202, e.g., between 5 kPa and 30 kPa, or between 10 kPa and 30 kPa.

[0068] In some embodiments, locating the orifice 204 at the bottom of the fluid container 202 may help to drain much or all of the cleaning fluid 220 and debris 300, as the orifice 204 is at least partially submerged throughout the entire cleaning process and substantially throughout the draining process. This allows a pressure driving force to be efficiently transferred to the cleaning fluid 220, driving it through the orifice 204.

[0069] In some embodiments, as shown in FIG. 3D , the roller 200 rotates in direction 312 while the cleaning liquid 220 is being discharged, such that the movement of the roller 200 moves the cleaning liquid 220 and any debris that has settled within the fluid container 202 towards the orifice 204, facilitating extraction of the cleaning liquid 220 and any debris that has settled within the fluid container 202.

[0070] As shown in FIGS. 3A-3D, a cleaning cycle begins with fresh cleaning fluid being pumped into the fluid reservoir, moves cleaning fluid onto the cleaning pad by rotating rollers to remove debris from the cleaning pad, and ends with used cleaning fluid and debris being drained from the fluid reservoir, e.g., into a waste tank. A cleaning cycle can be performed once or multiple times. For example, after draining cleaning fluid as shown in FIG. 3D, additional cleaning fluid can be supplied to the fluid reservoir 202 to further clean the pad, as shown in FIG. 3A. The number of cleaning cycles, or the decision not to perform additional cleaning cycles, can be determined by the robot, the control system 104, or a user device in communication with the control system 104. In some embodiments, cleaning cycles are performed until a threshold number of cleaning cycles have been performed. In some embodiments, cleaning cycles are performed until a threshold total amount of cleaning fluid has been transferred to the fluid reservoir and / or until the rollers have been activated for a threshold period of pad cleaning time over the cleaning cycle. In some embodiments, a cleaning cycle is run until the sensor 304 indicates that contamination of the cleaning fluid has stopped increasing during cleaning or is increasing at a rate below a threshold, indicating that little or no further debris is being removed from the cleaning pad. For example, during a cleaning cycle, the contamination level may be detected by the sensor 304 after pad cleaning, before cleaning fluid drainage, or before another cleaning cycle is run, and in response to the contamination level being below a threshold contamination level, a decision may be made not to run any further cleaning cycles.

[0071] In some embodiments, the threshold number of cleaning cycles, threshold amount of cleaning fluid, and / or threshold cleaning duration may be determined based on one or more of the following: the duration of cleaning (e.g., cleaning with a cleaning pad) performed by the robot in the most recent cleaning mission or since the most recent pad cleaning; the floor area (e.g., cleaning with a cleaning pad) cleaned by the robot in the most recent mission or since the most recent pad cleaning; the type of cleaning performed by the robot in the most recent cleaning mission or since the most recent pad cleaning (e.g., whether the floor surface cleaned with a cleaning pad was vacuumed using a cleaning pad); the duration (e.g., number of days) that the floor surface cleaned by the robot in the most recent cleaning mission had not been cleaned by the robot prior to the most recent cleaning mission; the soil level detected on the floor surface cleaned by the robot in the most recent cleaning mission or since the most recent pad cleaning (e.g., presence or absence of dirt or spills); the type of room the robot cleaned in the most recent cleaning mission or since the most recent pad cleaning (e.g., some room types, such as bathrooms and mudrooms, may have more pad cleanings compared to other room types, such as living rooms); the current season (e.g., more mud may be expected in a first season compared to a second season); or the current weather or the weather since the most recent pad cleaning (e.g., rain or snow may result in more pad cleanings).

[0072] In some embodiments, the threshold number of wash cycles, threshold amount of wash fluid, and / or threshold wash duration may be determined based on user input, for example, selections made in an application on the user device.

[0073] As shown in FIGS. 4A-4C, in some embodiments, the roller includes one or more types of surface features that can aid in the transport of cleaning fluid from the fluid reservoir to the cleaning pad, the hydraulic transport of cleaning fluid through the fibers of the cleaning pad, and / or agitation of the cleaning pad to improve debris removal. For example, as shown in FIG. 4A, roller 400a includes fletches 402. The fletches 402 protrude from the peripheral surface 406 of roller 400a and extend generally axially (longitudinal) along the length of roller 400a, for example, over halfway or across the entire length of roller 400a. In some embodiments, fletches 402 extend partially circumferentially as well as axially across roller 400a; for example, fletches 402 may wrap partially around the circumference of roller 400a. In some embodiments, the circumferential extension of fletches 402 is bidirectional. For example, from the proximal end 408 of the roller 400a, the fletch 402 extends counterclockwise around the circumference of the roller 400a to the center 404 of the roller 400a, where the fletch then extends clockwise to the distal end 410 (forming an overall generally V-shape). Other fletch shapes are within the scope of the present disclosure, such as one or more spiral fletches extending in a single clockwise or counterclockwise circumferential direction around and along the length of the roller. In some embodiments, the fletches help transfer cleaning fluid to the cleaning pad during roller rotation, acting as paddles / blades to lift the cleaning fluid. In some embodiments, the fletches further agitate the cleaning pad, thereby aiding in debris removal.

[0074] In some embodiments, as shown in FIG. 4B , roller 400b includes nubs 412 that protrude from a peripheral surface 414 of roller 400b. The nubs 412 extend only partially along the length of roller 400b. For example, in some embodiments, the length 416 of each nubs 412 is less than 3 cm, less than 2 cm, less than 1 cm, or less than 5 mm. The nubs 412 can be linear and / or curved and arranged in various patterns, such as a regular array. The nubs 412 aid in the movement of cleaning fluid and agitation of the cleaning pad, as described above.

[0075] In some embodiments, as shown in Figure 4C, the roller 400c can include lobes 418. The lobes 418 are smooth, continuous bulges and / or depressions that distort the surface of the roller 400c from an overall cylindrical shape. The lobes 418 can be arranged in a variety of patterns, such as a regular array.

[0076] Rollers according to the present disclosure may include one or more types of surface features, such as fletches, nubs, lobes, and / or other types of surface features, in any suitable combination, to aid in the movement of cleaning fluid and / or agitation of the pad.

[0077] FIG. 5 illustrates an example of a cleaning robot 122 docked to a cleaning station 102. For example, the drive system of the cleaning robot 122 (e.g., including one or more wheels 506) may operate to move the robot 122 over a surface 500 of the cleaning station 102. In various embodiments, the surface 500 may be inclined or parallel to the ground and may be referred to as a "docking surface" because the robot 122 docks with the cleaning station 102 on the surface 500. In some embodiments, the surface 500 has a surface topology, such as lateral ribs, that frictionally engage with the wheels 506 of the robot 122. The robot 122 moves to a position where the cleaning pad 124 attached to the pad holder 126 of the robot 122 contacts the roller 200 of the cleaning station. Conversely, the roller 200 is configured to contact the cleaning pad 124 when the robot 122 docks with the cleaning station 102 on the surface 500. For example, in some embodiments, as shown in FIG. 5, the fluid container 202 and roller 200 are placed in a recess 502 in the surface 500, the robot 122 docks over the recess 502, and the cleaning pad 124 contacts the roller 200.

[0078] In some embodiments, the robot 122 and / or cleaning station 102 includes a mechanism for pressing the cleaning pad 124 and roller 200 against one another. For example, in some embodiments, the load of the robot 122 itself (the weight of the robot 122) creates a force between the cleaning pad 124 and roller 200. In some embodiments, the cleaning station 102 includes a compression mechanism 512, such as a flexible tab, that engages the robot 122 or cleaning pad 124 and presses the cleaning pad 124 against the roller 200. In some embodiments, the cleaning station 102 includes a datum 514 that stops the movement of the robot 122 or cleaning pad 124 at a predetermined distance from the surface 500, thereby creating a set force between the cleaning pad 124 and roller 200. In some embodiments, the fluid container 202 and / or roller 200 are attached to the rest of the cleaning station 102 by a spring mount 510, such as a spring mount that holds the shaft 210 of the roller 200 or another portion of the fluid container assembly, and the spring force of the spring mount 510 biases the roller 200 against the cleaning pad 124. In some embodiments, the force between the cleaning pad 124 and the roller 200 can increase the agitation of the cleaning pad 124 by the roller 200, facilitating debris removal.

[0079] In some embodiments, the cleaning station 102 may receive dry debris from the robot 122 separate from the debris trapped on the cleaning pad 124. For example, as shown in FIG. 5 , the cleaning station 102 includes an intake port 116 positioned to interface with an exhaust port 508 of the robot 122. The exhaust port 508 is connected to a debris container (not shown) within the robot 122, which stores dry debris, such as debris sucked up by the robot 122. One or more pumps, blowers, and / or valves of the flow control system 112 operate to provide a vacuum to draw debris from the debris container through the exhaust port 508 and intake port 116 and into a waste tank or dry debris canister of the cleaning station 102.

[0080] As shown in FIGS. 6A and 6B, in some examples of relative movement between the cleaning pad 124 and the roller 200, the robot 122 moves relative to the roller 200. For example, the drive system of the robot 122 (e.g., wheels 506 of the robot 122) can operate to move the robot 122 over the surface 500 while the cleaning pad 124 contacts the roller 200 and the roller 200 rotates. Movement can be performed in multiple directions, with the robot 122 moving in direction 600a as shown in FIG. 6A and then moving in direction 600b as shown in FIG. 6B. In some embodiments, the relative movement between the cleaning pad 124 and the roller 200 can include a rotational component. For example, by rotating the wheels on one side (e.g., the left side) of the robot 122 forward and the wheels on the opposite side (e.g., the right side) of the robot 122 backward, rotation can be performed about a virtual axis internal to the robot, resulting in an overall rotation of the robot 122 and cleaning pad 124 relative to the roller 200. In some embodiments, the direction of rotation of the roller 200 corresponds to the direction of movement of the robot 122, with the portion of the roller 200 closest to the cleaning pad 124 moving in a direction opposite to the direction of movement of the robot 122. For example, in the configuration of FIG. 6A , the roller 200 may rotate counterclockwise, while in the configuration of FIG. 6B , the roller 200 may rotate clockwise. In some embodiments, during pad cleaning, the robot 122 sends a signal to the control system 104 indicating the current or planned direction of movement of the robot 122 relative to the cleaning station 102. In response, the control system 104 may rotate the roller 200 in the appropriate direction opposite the translation direction. In some embodiments, to enable the roller 200 to clean the entire length of the cleaning pad 124, the surface 500 has a length that allows the robot 122 to travel across (e.g., the length of) the cleaning pad 124 while the roller 200 is in contact with the cleaning pad 124.

[0081] 7A and 7B, in some examples of relative movement between the roller 200 and the cleaning pad (not shown), the fluid container assembly 114, or a portion thereof, moves relative to other portions of the cleaning station. For example, the fluid container assembly 114, or a portion thereof, may be attached to a movement mechanism 708 operable to move the fluid container assembly 114, or a portion thereof, relative to the cleaning pad during cleaning while the roller 200 rotates. The movement mechanism 708 may include, for example, tracks, rails, actuators, and / or another suitable mechanism type operable to move the fluid container assembly 114, or a portion thereof, relative to the cleaning pad. The movement may include forward / backward, left / right, and / or clockwise / counterclockwise movement relative to the cleaning station. For example, the movement mechanism 708 may be attached to the fluid container 202 or a bearing retainer, or to another component attached to the fluid container 202 or the roller 200. The cleaning station motor 704 (such as a servo motor or other suitable motor type) may be controlled by the control system 104 to operate a movement mechanism 708 to cause movement, which may be parallel or opposite to the direction of rotation of the roller, or perpendicular to the direction of rotation.

[0082] In some embodiments, the fluid container and roller move together. For example, as shown in FIGS. 7A and 7B, a cleaning station base 700 having a robot docking surface 500 includes an enlarged recess 702 recessed relative to the surface 500. The roller 200 and fluid container 202 together comprise a fluid container assembly 114 and can move together across the recess 702. The roller 200 and fluid container 202 can move together while maintaining their relative positions (the roller 200 is disposed within the fluid container 202), allowing cleaning operations (e.g., operations described with reference to FIGS. 3A-3D ) to continue normally during movement. The recess 702 can have dimensions (e.g., width or length) and / or the movement mechanism 708 can have a range that allows the roller 200 to move across the range (e.g., length) of the cleaning pad while in contact with the cleaning pad. In some embodiments, the fluid container 202 has an extended width that allows movement of the roller 200 relative to the fluid container 202, and the movement mechanism 708 can move the roller 200 while the fluid container 202 remains stationary.

[0083] The movement of the fluid container assembly 114, or a portion thereof, can be performed in multiple directions, i.e., as shown in Figure 7A, the fluid container assembly 114 moves in direction 710a, and then as shown in Figure 7B, the fluid container assembly 114 moves in direction 710b. In some embodiments, the rotation direction of the roller 200 is controlled by the control system 104 to correspond to the direction of movement of the fluid container assembly 114, such that the portion of the roller 200 near the cleaning pad moves in a direction that coincides with the direction of movement of the fluid container assembly 114 (opposite the direction of relative movement between the roller 200 and the cleaning pad). For example, in the configuration of Figure 7A, the roller 200 may rotate clockwise, and in the configuration of Figure 7B, the roller 200 may rotate counterclockwise.

[0084] 8A and 8B, in some examples of relative movement between the roller 200 and the cleaning pad 124, the cleaning robot 122 includes a movement mechanism 804 attached to the pad holder 126. The movement mechanism 804 is operable to move the pad holder 126 (and, along with the pad holder 126, the cleaning pad 124 attached to the pad holder 126) relative to the rest of the robot 122. The movement mechanism 804 may include, for example, tracks, rails, actuators, and / or another suitable mechanism type operable to move the pad holder 126. A motor 800 (such as a servo motor, linear screw motor, motor / gearbox unit, or other suitable motor type) within the robot 122 may be controlled by a control system of the robot 122 to operate the movement mechanism 804 to cause movement. In some embodiments, the motor 800 is a motor dedicated to moving the pad holder 126. In some embodiments, the motor 800 may also perform one or more other functions, and the control system of the robot 122 may appropriately reconfigure the mechanism of the robot 122 to use the motor to move the pad holder 126. The movement mechanism 804 may have a sufficient range to allow the movement to move the roller 200 across the range (e.g., length) of the cleaning pad 124 while the roller 200 is in contact with the cleaning pad 124.

[0085] In some embodiments, the robot 122 receives instructions from the cleaning station 102 and, in response to the instructions, moves the cleaning pad 124 relative to the cleaning station, for example, by initiating movement of the pad holder 126 and / or the robot 122 (using a drive system).

[0086] The movement of the pad holder 126 can be performed in multiple directions. As shown in FIG. 8A, the pad holder 126 and cleaning pad 124 move in direction 802a, and then, as shown in FIG. 8B, the pad holder 126 and cleaning pad 124 move in direction 802b. In some embodiments, the rotation direction of the roller 200 corresponds to the movement direction of the pad holder 126, with the portion of the roller 200 closest to the cleaning pad 124 moving in the opposite direction to the movement direction of the cleaning pad 124. For example, in the configuration of FIG. 8A, the roller 200 may rotate counterclockwise, while in the configuration of FIG. 8B, the roller 200 may rotate clockwise. In some embodiments, during pad cleaning, the robot 122 sends a signal to the control system 104 indicating the current or planned direction of movement of the pad holder 126 relative to the cleaning station 102. In response, the control system 104 can rotate the roller 200 in the appropriate direction opposite the movement direction.

[0087] The pad holder 126, whether movable by a movement mechanism or not, may include a pad plate and a suitable attachment mechanism for securely holding the cleaning pad 124 to the pad plate during pad cleaning. For example, the pad holder 126 may include a Velcro® attachment area, clips, straps, hooks, buttons, and / or other suitable attachment types.

[0088] 6A-8B may be included and operate simultaneously, e.g., to increase the speed of relative movement and further increase hydraulic pressure and / or agitation to facilitate debris removal. Additionally, in some embodiments, the rotation of the roller is performed in the opposite direction to that described with reference to Figures 6A-8B, e.g., the portion of the roller 200 closer to the cleaning pad 124 moves in a direction that coincides with the direction of relative movement of the cleaning pad 124.

[0089] As shown in FIG. 9 , in some embodiments, the cleaning station 102 includes a cleaning solution tank 108 and a waste tank 110. The cleaning solution tank 108 stores fresh cleaning solution and can be filled by a user, e.g., include an input port through which a user can pour the cleaning solution. The cleaning solution can include, e.g., water or a soapy cleaning solution. The waste tank 110 stores the cleaning solution used to remove debris from the cleaning pad and, in some embodiments, also stores the removed debris. The waste tank 110 can be emptied by a user, e.g., include an output port through which a user can pour the contents of the waste tank 110. Either or both the cleaning solution tank 108 or the waste tank 110 can be removable from the cleaning station 102, allowing for easy filling, draining, and / or manual cleaning of the tanks.

[0090] In the example of FIG. 9 , the cleaning solution tank 108 is fluidly coupled to the fluid container assembly 114 by a conduit 900a that couples to two inlet orifices of the fluid container of the fluid container assembly 114. The waste tank 110 is fluidly coupled to the fluid container assembly 114 by another conduit 900b that couples to another orifice of the fluid container. The flow control system of the cleaning station 102 may operate to flow fresh cleaning solution from the cleaning solution tank 108 to the fluid container via conduit 900a and to drain used cleaning solution, along with debris, from the fluid container to the waste tank 110 via conduit 900b. Other embodiments according to the present disclosure may include a single orifice through which cleaning solution enters and exits the fluid container. Any of the embodiments according to the present disclosure may include one or both configurations, such as orifices / conduits dedicated to either the inflow or outflow of cleaning solution and / or orifices / conduits used for both the inflow and outflow of cleaning solution. The inclusion of separate conduits and / or orifices for the inlet and outlet of cleaning fluids can reduce mixing of clean and used fluids and improve cleaning effectiveness.

[0091] In some embodiments, the cleaning station 102 includes one or more sensors for detecting (i) the fill level of the cleaning solution tank 108 and / or (ii) the fill level of the waste tank 110. In some embodiments, when the fill level of the cleaning solution tank 108 drops to zero or below a threshold, the cleaning station 102 can send a notification (e.g., to a user device) indicating that a user needs to refill the cleaning solution tank 108. In some embodiments, a pump or sensor in the flow control system 112 can be configured to monitor the cumulative amount of cleaning solution delivered to the cleaning container assembly, and the fill level of the cleaning solution tank 108 and / or the waste tank 110 can be determined based on the cumulative amount. In some embodiments, when the fill level of the waste tank 110 is full or exceeds a threshold, the cleaning station 102 can send a notification (e.g., to a user device) indicating that a user needs to empty the waste tank 110.

[0092] While it may be convenient to remove small debris from the fluid container with used cleaning fluid, larger debris can clog the cleaning station conduits and prevent fluid flow. Therefore, in some embodiments, a shielding mechanism, such as a septum 1000, is placed at the orifice 204 near the fluid container 202 or the conduit 208, as shown in FIG. 10 . The septum 1000 is sized to prevent debris above a threshold size from flowing through the conduit 208. For example, the septum 1000 may be sized to prevent objects greater than about 1 cm in diameter from flowing through the conduit 208. In some embodiments, the septum 1000 is positioned laterally in the center of the fluid flow path. For example, the septum 1000 may be attached to the ceiling of the conduit 208 at the lateral center of the conduit 208, allowing cleaning fluid and debris to flow to the left, right, and bottom of the septum 1000. Hair, sand, dust, and other small debris flow through without significant obstruction, while larger debris becomes blocked and remains within the fluid enclosure 202 or orifice 204. In some embodiments, instead of or in addition to a septum, another type of blocking mechanism, such as a cage filter, may be placed within the orifice 204 or conduit 208 to limit the size of debris that is discharged from the fluid enclosure 202. In some cases, a septum may improve the user experience compared to a filter because it reduces clogging with debris that requires the user to remove it. Debris blocked by the blocking mechanism can be manually removed by the user, which is convenient because the blocking mechanism is located in close proximity to the fluid enclosure 202 and does not require the user to access the internal components of the cleaning station.

[0093] In some embodiments, one or more sensors are incorporated into the fluid enclosure assembly to detect whether large debris is interfering with the roller's performance. For example, one or more sensors may be incorporated into the roller and configured to detect whether the roller has stopped rotating, is rotating slower than desired, and / or is drawing more current than a baseline current level in the roller motor, any of which may be indicative of large debris interfering with the roller's rotation. Detection may be performed during a cleaning cycle or during a calibration test performed separately from the cleaning cycle (e.g., when the roller is not engaged with the cleaning pad) (e.g., to check current consumption against a baseline current level). In some embodiments, the sensor includes a rotational sensor, such as a rotary optical encoder, that senses the rotation of the roller. The sensor is communicatively coupled to the control system 104, and in some embodiments, the control system 104 may perform one or more actions in response to the detection of large debris. For example, in some embodiments, the control system 104 may stop pad cleaning in response to the detection of large debris. In some embodiments, the control system 104 may send a notification to a user device indicating that the user should remove large debris from the fluid enclosure 202.

[0094] While some of the cleaning station embodiments described so far include only a single roller and a single fluid container, some embodiments may include multiple rollers and multiple fluid containers, with each roller disposed within a corresponding fluid container. For example, as shown in FIG. 11 , cleaning station 1100 includes two fluid container assemblies 114a, 114b, each of which has some or all of the characteristics described for fluid container assembly 114. For example, each of assemblies 114a, 114c may include a respective roller disposed within a respective fluid container, have one or more orifices coupled to one or more conduits to allow the inflow / outflow of cleaning fluid, and, in some embodiments, be movable by a movement mechanism. In some embodiments, assemblies 114a, 114b are disposed parallel to one another, e.g., allowing the rollers of assemblies 114a, 114b to rotate parallel to one another. In some embodiments, the rollers of the assemblies extend along a direction 1104 that corresponds to the short dimension 1106, rather than the long dimension 1110, of the cleaning pad 1108 when the cleaning pad 1108 is positioned to be cleaned by the assemblies 114a, 114b, as shown for assemblies 114a, 114b. For example, for a given cleaning pad 1108, the length of the rollers of assemblies 114a, 114b may be shorter than the length of the rollers of the fluid container assembly 114 shown in FIG. 9. This configuration may be useful, for example, in embodiments where the robot rotates about an imaginary axis due to motion caused by counter-rotation of the robot's wheels, which may reduce the angle through which the robot rotates to fully cover the cleaning pad. The assemblies 114a, 114b are movable along the dimension 1110, allowing the entire length of the cleaning pad 1108 to be cleaned together. In some embodiments, multiple assemblies may be arranged along a direction perpendicular to direction 1104, for example, extending along the longer dimension 1110 of the cleaning pad 1108.

[0095] In some embodiments, the cleaning station includes one or more fluid containers, with multiple rollers disposed in at least one of the fluid containers. For example, as shown in FIG. 12, cleaning station 1200 includes a fluid container assembly 1202 with a fluid container 1204 and two rollers 1206a, 1206b. The fluid container 1204 can be shaped sufficiently to accommodate both rollers 1206a, 1206b, e.g., wider than a fluid container that holds only a single roller. During pad cleaning, rollers 1206a, 1206b can rotate simultaneously, e.g., in the same or opposite directions. For example, in some embodiments, a first roller (e.g., roller 1206b) rotates counterclockwise and the other roller (e.g., roller 1206a) rotates clockwise, with the action of both rollers drawing fluid up between the two rollers. In some embodiments, the relative movement between the cleaning pad and rollers 1206a, 1206b can be performed so that more than half or all of the cleaning pad is cleaned (e.g., contacted) by both rollers 1206a, 1206b during the pad cleaning process. The use of two rollers can improve pad cleaning, for example, by increasing the amount of debris removed from the pad or by reducing the amount of time the cleaning pad needs to be cleaned to remove a given amount / percentage of debris. While FIG. 12 shows two rollers 1206a, 1206b extending horizontally (e.g., perpendicular to the extension direction of the rollers of fluid container assemblies 114a, 114b in FIG. 11), in some embodiments, the two rollers in a common fluid container assembly can be oriented as shown for fluid container assemblies 114a, 114b.

[0096] The features described with reference to FIGS. 2A-12 may provide advantages to pad cleaning compared to at least some other pad cleaning approaches. For example, as described with reference to FIGS. 3A-3D, hydraulic pad cleaning combined with pad agitation improves debris removal compared to pad scraping methods. Rapid extraction of contaminated fluid from the fluid container removes all or nearly all debris from the fluid container, reducing the amount of user interaction required to maintain the cleaning system (e.g., other than emptying the waste tank when it becomes full). For example, this reduces the amount of user interaction compared to sieve-based approaches, where users are expected to routinely interact with the soiled portions of the device. Furthermore, the use of a fluid container and roller combination may reduce the impact of pad cleaning-related contaminants, such as used cleaning fluid and debris, on the cleaning station. Excluding conduits and other flow-related components, only the fluid container and roller are exposed to used cleaning fluid and debris, requiring relatively little surface area for manual cleaning by the user, and the contaminants are contained in a relatively small, easily accessible fluid container that, in some embodiments, can be removed from the cleaning station. In some cases, manual cleaning (other than removal of larger debris) may not be necessary at all. In contrast, some alternative schemes result in large surface areas contaminated with used cleaning fluid and debris, which reduces pad cleaning performance over time without tedious manual cleaning by the user. Furthermore, because the cleaning fluid is reused throughout each cleaning cycle (drawn into the cleaning pad, directed into the fluid reservoir, and drawn back into the cleaning pad), the total amount of cleaning fluid used is reduced compared to other methods, reducing the costs and user time associated with refilling the cleaning fluid.

[0097] In various embodiments, various combinations and configurations of conduits, containers, and flow control system components may be used to capture and store waste. For example, dry debris and debris from the cleaning pad may be extracted separately or at least partially through a common path, and dry debris and debris from the cleaning pad may be stored separately or together in a common waste container. Figures 13-16 show some examples of waste capture devices and their components.

[0098] As shown in FIG. 13 , in some embodiments, a waste tank 110 is positioned to contain used cleaning solution and debris resulting from pad cleaning, and a separate dry debris canister 106 is positioned to contain dry debris from the cleaning robot. The waste tank 110 is fluidly coupled (e.g., by conduits) to one or more fluid containers 202, and the dry debris canister 106 is fluidly coupled to an intake port 116. In some embodiments, separate pumps / blowers are used to transfer the cleaning solution / debris to the separate waste tank 110 and dry debris canister 106. In some embodiments, a common pump / blower drives transfer to both containers. For example, as shown in FIG. 13 , the blower 1304 can apply a vacuum to either the waste tank 110 or the dry debris canister 106, depending on the configuration of the valve 1302. In a first configuration of the valve 1302, the blower 1304 applies a vacuum and sends a flow of cleaning solution and debris from the fluid containers 202 to the waste tank 110. In a second configuration of the valve 1302, the blower 1304 applies a vacuum to send a flow of dry debris from the inlet port 116 (e.g., the exhaust port of a cleaning robot) to the dry debris canister 106. The valve 1302 may be switched between configurations by the control system 104. One or more elements may prevent cleaning fluid / debris from flowing through the waste tank 110 or the dry debris canister 106 to the valve 1302, as described in FIG. 16 . In some embodiments, the dry debris canister 106 includes a filter, such as a mesh filter, to retain solid debris within the dry debris canister 106 and allow air sent by the blower 1304 to pass from the dry debris canister 106, for example, to the valve 1302.

[0099] 14, a common waste tank 110 is positioned to receive both the cleaning fluid / debris from the fluid container 202 and the dry debris from the inlet port 116. For example, a valve 1402 controlled by the control system 104 may switch between coupling the fluid container 202 to the waste tank 110 or coupling the inlet port 116 to the waste tank 110. When the pump or blower 1304 is activated, the generated vacuum draws the cleaning fluid and / or debris from the fluid container 202 or the inlet port 116, whichever is connected to the waste tank 110, through the valve 1402 and into the waste tank 110.

[0100] In some embodiments, the waste tank 110 includes features that separate liquid waste, such as used cleaning solution, from solid waste, such as debris removed from a cleaning pad or extracted from a cleaning robot's debris container. For example, as shown in FIG. 16 , the waste tank 110 may include a solid waste canister 1502, a liquid waste canister 1504, and an element 1506, such as a filter, that directs or retains solid waste into the solid waste canister 1502 and liquid waste into the liquid waste canister 1504. For example, the element 1506 may include a washable mesh strainer, a washable fabric filter, a disposable mesh or fabric filter, or an inertial separation device, for example, based on cyclonic motion. In some embodiments, the solid waste canister 1502 is disposed within the liquid waste canister 1504. For example, the solid waste canister 1502 may be separately removable from the liquid waste canister 1504 for easy emptying by a user.

[0101] In some embodiments, one or more air separation elements are provided to separate the liquid waste from the airflow generated by the pump or blower, so that the liquid is retained in the waste tank 110. As shown in FIG. 16, one or more air separation elements 1602a, 1602b may be provided within the waste tank 110, between the waste tank 110 and the blower 1304, or both, and / or at another location. For example, the air separation element 1602a (e.g., a post-filter) may be provided between the waste tank 110 and a valve, as in the configuration of FIG. 13. In some embodiments, the air separation element 1602b is integrated into the waste tank 110, e.g., disposed at least partially within the waste tank 110. For example, the air separation element 1602b may be integrated into the liquid waste canister 1504, e.g., within the liquid waste canister 1504. The air separation elements 1602a, 1602b may include one or more of the following: For example, a tortuous path that allows the passage of gas but not liquid (e.g., a tortuous path defined by a conduit); a chamber and / or conduit shaped to reduce fluid velocity so that the cleaning liquid falls out of the airflow, e.g., an inertial separator based on cyclonic motion; or an air-only permeable membrane that blocks the flow of liquid but allows the flow of gas.

[0102] In some embodiments, a drying element 1604 is included after the air separation element 1602 removes moisture from the air stream. For example, the drying element 1604 may include a foam or fabric filter, an evaporation chamber, and / or inertial separation. After the drying element 1604, the dry air is released from the cleaning station into the surrounding environment.

[0103] FIG. 17 illustrates an example of a mobile cleaning robot 122 according to some embodiments of the present disclosure. The mobile cleaning robot 122 includes a pad holder 126 sized and shaped to hold a corresponding cleaning pad. For example, in some embodiments, the pad holder has a shape that matches the shape of the cleaning pad. For example, the pad holder 126 may be crescent-shaped to hold a crescent-shaped cleaning pad 1108. A drive system 1702, such as a motor and one or more locomotion devices, operates to move the robot across a floor surface. For example, the locomotion devices may include wheels or track elements. In some embodiments, a vacuum system 1708 includes one or more suction elements operable to suck debris from the floor surface and store the debris in a debris container 1706. In some embodiments, the debris container 1706 is removable from the robot 122 for emptying. In some embodiments, the debris container 1706 is coupled to an exhaust port 508 for evacuation by a cleaning station. In some embodiments, the robot 122 does not include a vacuum element and cleans using only a cleaning pad attached to the pad holder 126 .

[0104] In some embodiments, the robot 122 includes a movement mechanism operable to move the pad holder 126 relative to the rest of the cleaning robot 122 (e.g., the body of the cleaning robot), e.g., as described with reference to Figures 7A and 7B. In some embodiments, the control system 1700 of the robot 122 is configured such that the drive system 1702 moves the robot 122 relative to the cleaning station when a cleaning pad attached to the pad holder 126 is to be cleaned by the cleaning station, e.g., as described with reference to Figures 6A and 6B.

[0105] The control system 1700 may include a computer system configured to control the operation of one or more components of the robot 122, for example, by receiving data / signals from the components and providing data / signals to the components. In some embodiments, the robot 122 includes a communication system 1704 configured to send and receive signals to one or more other devices, such as a cleaning station, a user device, and / or a remote computer system (e.g., a cloud computer system). For example, the communication system 1704 can send and receive wireless signals, such as short-range signals (e.g., Bluetooth), medium-range signals (e.g., Wi-Fi), and / or cellular network signals.

[0106] The disclosed and other exemplary operations related to pad cleaning, e.g., control operations performed by a control system (e.g., control system 104 and / or control system 1700) to cause fluid flow, signal transmission, roller rotation, translation, etc., may be implemented as one or more computer program products, e.g., one or more modules of computer program instructions encoded on a computer-readable medium for execution by or controlling the operation of a data processing device. The computer-readable medium may be a machine-readable storage device, a machine-readable storage substrate, a memory device, or one or more combinations thereof. The terms "data processing device" or "computer system" include all apparatuses, devices, and machines that process data, including, by way of example, a programmable processor, a computer, or multiple processors or computers. This apparatus may be included in a control system. In addition to hardware, this apparatus may include code that creates an execution environment for the subject computer program, such as code comprising processor firmware, a protocol stack, a database management system, an operating system, or one or more combinations thereof.

[0107] A system (e.g., a computer system) includes all apparatus, devices, and machines for processing data, such as a programmable processor, a computer, or multiple processors or computers. In addition to hardware, a system may include code that creates an execution environment for a subject computer program, such as code comprising processor firmware, a protocol stack, a database management system, an operating system, or one or more combinations thereof. Examples of computer systems may include control system 1700 and control system 104.

[0108] A computer program (also called a program, software, software application, script, or code) may be written in any form of programming language, including compiled or interpreted languages, and may be deployed in any form, such as a stand-alone program or as a module, component, subroutine, or other unit suitable for use in a computing environment. A computer program does not necessarily correspond to a file in a file system. A program may be stored as part of a file that holds other programs or data (e.g., one or more scripts stored in a markup language document), in a single file dedicated to the program, or in multiple coordinated files (e.g., a file storing one or more modules, subprograms, or portions of code). A computer program may be deployed to run on a single computer or on multiple computers located at a single site or distributed across multiple sites and interconnected by a communications network.

[0109] The processes and logic flows described herein may be performed by one or more programmable processors executing one or more computer programs to perform the functions described herein. The processes and logic flows may also be performed by, or devices may be implemented as, special purpose logic circuitry, such as an FPGA (Field Programmable Gate Array) or an ASIC (Application Specific Integrated Circuit).

[0110] Processors suitable for executing a computer program include, by way of example, both general-purpose and special-purpose microprocessors, as well as one or more processors of any kind of digital computer. Typically, a processor receives instructions and data from a read-only memory or a random-access memory, or both. Essential elements of a computer may include a processor for executing instructions and one or more memory devices for storing instructions and data. Typically, a computer will include one or more mass storage devices for storing data, such as magnetic disks, magneto-optical disks, or optical disks, or will be operatively coupled to receive data from, transfer data to, or both. However, a computer need not require such devices. Computer-readable media suitable for storing computer program instructions and data include all forms of non-volatile memory, media, and memory devices (e.g., semiconductor memory devices such as EPROMs, EEPROMs, flash memory devices, magnetic disks, etc.). The processor and memory may be supplemented by, or incorporated in, special-purpose logic circuitry.

[0111] While some examples have been set forth for illustrative purposes, the foregoing descriptions are not intended to limit the scope of the embodiments disclosed herein. Other examples and modifications exist and will continue to exist within the scope of the following claims. [Explanation of symbols]

[0112] 100 systems 102 Cleaning Station 104 Control System 106 Dry Debris Canister 108 Cleaning liquid tank 110 Waste Tank 112 Flow Control System 114 Fluid container assembly 116 Intake port 118 Conduit 120 Housing 122 Mobile cleaning robot 124 cleaning pad 126 Pad Holder 128 sensors 130 Moving mechanism 132 Motor 134 Communication Systems 200 Roller 201 Center axis 202 Fluid container 204 Orifice 206 Bearing 208 Conduit 210 Shaft 212 Tubular body 214 Bearing holder 216 Fletch 218 Side wall 220 cleaning solution 222 diameter 230 Holder 236 Liquid level 240 Shortest Distance 242 Upper 250 reservoir 300 Debris 301 Fluid containers 302 Bottom 304 Sensor 308, 312 direction 400 Roller 402 Fletch 404 center 406 Surface 408 Proximal end 410 Distal end 412 Protrusion 414 Surface 418 Robe 500 surface 502 recess 506 wheels 508 exhaust port 512 Compression mechanism 600 directions 700 base 702 recess 704 Motor 708 Moving mechanism 710 800 motor 802 directions 804 Moving mechanism 900 Conduit 1000 Bulkhead 1100, 1200 Cleaning Station 1108 Cleaning Pad 1202 Fluid Container Assembly 1204 Fluid containers 1206 Roller 1302, 1402 valves 1304 Blower 1502 Solid Waste Canister 1504 Liquid Waste Canister 1602 Air Separation Element 1604 Drying element 1700 Control System 1702 Drive System 1704 Communication Systems 1706 Debris container 1708 Vacuum System

Claims

1. 1. A cleaning station for a mobile robot, comprising: a fluid container; a roller disposed within the fluid reservoir, the fluid reservoir configured to hold a cleaning fluid that at least partially immerses the roller; a control system configured to rotate the roller when the mobile robot docks with the cleaning station to direct cleaning fluid from the fluid container onto a cleaning pad of the mobile robot and remove debris from the cleaning pad; A cleaning station comprising:

2. The cleaning station of claim 1 , wherein the roller is translatable relative to the mobile robot during rotation of the roller.

3. The cleaning station of claim 2 , further comprising a translation mechanism attached to the fluid container, the translation mechanism operable to translate the roller relative to the mobile robot during rotation of the roller.

4. The cleaning station of claim 1 , further comprising a docking surface for receiving the mobile robot, the fluid container being disposed in a recess in the docking surface.

5. the roller is positioned to contact the cleaning pad; 5. The cleaning station of claim 4, wherein the docking surface has a length that allows the mobile robot to move through the extent of the cleaning pad when the mobile robot is docked at the cleaning station with the roller in contact with the cleaning pad.

6. 10. The cleaning station of claim 1, wherein the control system is configured to rotate the roller so that a portion of the roller near the cleaning pad moves in a direction opposite to a direction of relative translation between the roller and the cleaning pad.

7. 10. The cleaning station of claim 1, wherein the roller comprises at least one of one or more fletches extending along the length of the surface of the roller, one or more nubs projecting from the surface of the roller, or one or more lobes smoothly distorting the surface of the roller.

8. The cleaning station of claim 1 , wherein the roller comprises an elastomer.

9. The cleaning station of claim 1 , wherein the roller is positioned to contact the cleaning pad when the mobile robot is docked at the cleaning station.

10. a spring-loaded mounting portion to which the roller is attached; The cleaning station of claim 9 , wherein the spring-loaded mounting is arranged to press the roller against the cleaning pad.

11. The cleaning station of claim 1 , wherein rotation of the roller directs cleaning fluid onto the cleaning pad and back into the fluid reservoir.

12. a conduit fluidly coupled to the fluid container; 2. The cleaning station of claim 1, wherein during a cleaning cycle, the control system is configured to cause cleaning fluid to flow into the fluid container and to expel the cleaning fluid from the fluid container through the conduit after the cleaning fluid has been forced into the cleaning pad.

13. The cleaning station of claim 12 , comprising a vacuum source configured to provide a vacuum to draw cleaning fluid from the fluid container.

14. 14. The cleaning station of claim 13, wherein the vacuum source creates a negative pressure of 5 kPa to 30 kPa against the fluid container when the control system draws cleaning fluid.

15. 13. The cleaning station of claim 12, wherein cleaning liquid is discharged through the conduit at a velocity of from 0.5 m / s to 4.0 m / s.

16. 13. The cleaning station of claim 12, further comprising a septum disposed within the conduit, the septum sized to limit the size of debris flowing through the conduit.

17. a sensor disposed within the fluid container and communicatively connected to the control system, the sensor configured to measure a contamination level of cleaning fluid within the fluid container; The cleaning station of claim 12 , wherein the control system is configured to drain the cleaning fluid from the fluid container in response to a contamination level exceeding a threshold.

18. the control system is configured to repeat the cleaning cycle until a threshold number of cycles have been performed or a threshold amount of cleaning fluid has passed through the cleaning pad; 13. The cleaning station of claim 12, wherein the threshold number of cycles or threshold volume of cleaning fluid is based on at least one of the duration of cleaning by the mobile robot, the area of the environment to be cleaned by the mobile robot, the type of cleaning by the mobile robot, the time a floor surface has not been cleaned by the mobile robot, the level of soiling detected by the mobile robot, the type of room to be cleaned by the mobile robot, the current season, or current or past weather.

19. a sensor disposed within the fluid container and communicatively connected to the control system, the sensor configured to measure a contamination level of cleaning fluid within the fluid container; 13. The cleaning station of claim 12, wherein the control system is configured to repeat the wash cycle until the contamination level falls below a threshold at a predetermined time during the wash cycle.

20. The cleaning station of claim 12, wherein the control system is configured to cause cleaning fluid to flow into the fluid container until between 15% and 50% of the height of the roller is submerged in cleaning fluid.

21. 10. The cleaning station of claim 1, comprising a waste tank fluidly coupled to a fluid container, a dry debris canister, a vacuum source, and a valve. In a first configuration of the valve, the valve fluidly couples the vacuum source to the waste tank, and a vacuum applied by the vacuum source draws cleaning fluid from the fluid container into the waste tank; 2. The cleaning station of claim 1, wherein in a second configuration of the valve, the valve fluidly couples the vacuum source to the dry debris canister, and a vacuum applied by the vacuum source draws dry debris stored within the mobile robot into the dry debris canister.

22. 10. The cleaning station of claim 1, comprising a waste tank, a vacuum source, and a valve. In a first configuration of the valve, the valve fluidly couples the waste tank to a fluid container, and a vacuum applied by the vacuum source draws cleaning fluid from the fluid container into the waste tank; 2. The cleaning station of claim 1, wherein in a second configuration of the valve, the valve fluidly couples the vacuum source to an exhaust port of a mobile robot such that a vacuum applied by the vacuum source draws dry debris stored within the mobile robot into the waste tank.

23. 10. The cleaning station of claim 1, comprising a waste tank fluidly coupled to a fluid container, a solid waste canister fluidly coupled to the fluid container, a vacuum source, and a filter. The cleaning station of claim 1 , wherein the filter is configured to receive a mixture of debris and cleaning fluid from the fluid container and direct the debris to the solid waste canister and the cleaning fluid to the waste tank.

24. 10. The cleaning station of claim 1, wherein the roller is a first roller and the cleaning station further comprises a second roller disposed within the fluid reservoir or within a second fluid reservoir of the cleaning station.

25. a drive system for maneuvering the mobile cleaning robot through an environment during a cleaning mission; a pad holder for receiving a fabric pad for removing and capturing debris from a floor surface; a control system configured to dock the mobile cleaning robot to a docking station for cleaning a fabric pad in a pad cleaning routine and to move the fabric pad relative to the docking station during the pad cleaning routine; A mobile cleaning robot comprising:

26. 26. The mobile cleaning robot of claim 25, comprising a movement mechanism attached to the pad holder, the movement mechanism operable to move the fabric pad relative to the docking station.

27. 26. The mobile cleaning robot of claim 25, wherein moving the fabric pad relative to the docking station comprises causing the drive system to maneuver the mobile cleaning robot relative to the docking station.

28. 26. The mobile cleaning robot of claim 25, wherein moving the fabric pad relative to the docking station comprises moving the fabric pad relative to the docking station in response to receiving a command from the docking station.

29. a cleaning station with a roller; a mobile robot having a pad holder for receiving a fabric pad for removing and capturing debris from a floor surface; A system comprising: the roller is positioned to contact the fabric pad when the mobile robot is docked at a cleaning station for a pad cleaning routine; At least one of the cleaning station or the mobile robot is configured to cause relative movement between the fabric pad and the roller during a pad cleaning routine.

Images