Mobile Cleaning Robot with Debris Compaction

This patent application claims the benefit of priority, under 35 U.S.C. Section 119 (e), to Timothy Ohm U.S. Patent Application Ser. No. 63/648,813, entitled “MOBILE CLEANING ROBOT WITH DEBRIS COMPACTION,” filed on May 17, 2024, which is hereby incorporated by reference herein in its entirety.

Autonomous mobile robots include autonomous mobile cleaning robots that can autonomously perform cleaning tasks within an environment, such as a home. Many kinds of cleaning robots are autonomous to some degree and in different ways. Some robots can perform vacuuming operations and some can perform mopping operations. Other robots can include components or systems to perform both vacuuming and mopping operations. Most types of mobile cleaning robots can interface with a docking station that can perform maintenance on the robot, such as charging and debris evacuation.

Certain mobile cleaning robots can be configured to collect and store debris within their body, such as in a debris bin. However, the bins must be emptied from time to time to allow for proper operation. It may be desirable to reduce a frequency of emptying a debris bin of debris; however, space is relatively limited within the body of the robot and it is therefore difficult to increase a size of the debris bin.

To help address these issues, this disclosure discusses solutions including a debris compactor located at least partially within the robot where the compactor can be configured to receive debris from the extractor of the robot and compact the debris into the debris bin, which can significantly reduce a frequency at which the debris bin must be emptied.

For example, a mobile cleaning robot can include a body, a debris bin connected to the body, and one or more drive wheels connected to the body and operable to move the mobile cleaning robot about an environment. The mobile cleaning robot can include an extractor connected to the body that can be operable to extract debris from the environment. The mobile cleaning robot can also include a vacuum system connected to the body and configured to generate a flow stream through the extractor. The mobile cleaning robot can include a compaction system connected to the body and a discharge of the extractor. The compaction system can include a plenum configured to receive debris and the flow stream from the discharge and a compactor located at least partially within the plenum and operable to compact debris from the plenum into the debris bin.

The above discussion is intended to provide an overview of subject matter of the present patent application. It is not intended to provide an exclusive or exhaustive explanation of the invention. The description below is included to provide further information about the present patent application.

illustrates a plan view of a mobile cleaning robotin an environment. The environmentcan be a dwelling, such as a home or an apartment, and can include rooms-. Obstacles, such as a bed, a table, and an islandcan be located in the roomsof the environment. Each of the rooms-can have a floor surface-, respectively. Some rooms, such as the room, can include a rug, such as a rug. The floor surfacescan be of one or more types such as hardwood, ceramic, low-pile carpet, medium-pile carpet, long (or high)-pile carpet, stone, or the like.

The mobile cleaning robotcan be operated, such as by a user, to autonomously clean the environmentin a room-by-room fashion. In some examples, the robotcan clean the floor surfaceof one room, such as the room, before moving to the next room, such as the room, to clean the surface of the room. Different rooms can have different types of floor surfaces. For example, the room(which can be a kitchen) can have a hard floor surface, such as wood or ceramic tile, and the room(which can be a bedroom) can have a carpet surface, such as a medium pile carpet. Other rooms, such as the room(which can be a dining room) can include multiple surfaces where the rugis located within the room. The robotcan be configured to navigate over various floor types through one or more components such as a suspension. The suspension of the robot can also allow the robotto navigate over obstacles, such as thresholds between rooms or over rugs, such as the rug.

Also during cleaning or traveling operations, the robotcan use data collected from various sensors (such as optical sensors) and calculations (such as odometry and obstacle detection) to develop a map of the environment. Once the map is created, the usercan define rooms or zones (such as the rooms) within the map. The map can be presentable to the useron a user interface, such as a mobile device, where the usercan direct or change cleaning preferences, for example.

Also, during operation, the robotcan detect surface types within each of the rooms, which can be stored in the robot or another device. The robotcan update the map (or data related thereto) such as to include or account for surface types of the floor surfaces-of each of the respective roomsof the environment. In some examples, the map can be updated to show the different surface types such as within each of the rooms.

illustrates a bottom view of the mobile cleaning robot.illustrates a bottom view of the mobile cleaning robot.illustrates a cross-section view across indicators-ofof the mobile cleaning robot.also shows orientation indicators Bottom, Top, Front, and Rear.are discussed together below.

The cleaning robotcan be a mobile cleaning robot that can autonomously traverse the floor surfacewhile ingesting the debrisfrom different parts of the floor surface. As depicted in, the robotcan include a bodymovable across the floor surface. The bodycan include multiple connected structures to which movable components of the cleaning robotcan be mounted. The connected structures can include an outer housing to cover internal components of the cleaning robot, a chassis to which drive wheelsandand the cleaning rollersand(of a cleaning assembly or extractor) are mounted, and a bumpermounted to the outer housing.

As shown in, the bodycan include a front portionthat has a substantially semicircular shape and a rear portionthat has a substantially semicircular shape. As shown in, the robotcan include a drive system including actuatorsand, e.g., motors, operable with drive wheelsand. The actuatorsandcan be mounted in the bodyand can be operably connected to the drive wheelsand, which are rotatably mounted to the body. The drive wheelsandcan support the bodyabove the floor surface. The actuatorsand, when driven, can rotate the drive wheelsandto enable the robotto move across the floor surface.

The controller (or processor)can be located within the housingand can be a programable controller, such as a single or multi-board computer, a direct digital controller (DDC), a programable logic controller (PLC), or the like. In other examples the controllercan be any computing device, such as a handheld computer, for example, a smart phone, a tablet, a laptop, a desktop computer, or any other computing device including a processor and communication capabilities. The memorycan be one or more types of memory, such as volatile or non-volatile memory, read-only memory (ROM), random-access memory (RAM), magnetic disk storage media, optical storage media, flash-memory devices, and other storage devices and media. The memorycan be located within the housingand can be connected to the controllerand accessible by the controller.

The controllercan operate the actuatorsandto autonomously navigate the robotabout the floor surfaceduring a cleaning operation. The actuatorsandare operable to drive the robotin a forward drive direction, in a backwards direction, and to turn the robot. The robotcan include a caster wheel(or alternatively skids) that supports the bodyabove the floor surface. The castercan support the front portionof the bodyabove the floor surface, and the drive wheelsandsupport a middle and rear portionof the bodyabove the floor surface.

As shown in, a vacuum assemblycan be located within the bodyof the robot, e.g., in the middle of the body. The controllercan operate the vacuum assemblyto generate an airflow that flows through the air gap near the cleaning rollersand, through the body, and out of the body. The vacuum assemblycan include, for example, an impeller that generates the airflow when rotated. The airflow and the cleaning rollersand, when rotated, cooperate to ingest debrisinto the robot, such as into a dischargeof the extractor, where the dischargecan be a tube, duct, or the like. A debris bincan be mounted in the bodyand connected to the discharge. The debris bincan be configured to receive and contain the debrisingested by the robot. A filter(that can be located at least partially within the debris bin) can separate the debrisfrom the airflow before the airflowenters the vacuum assemblyand is exhausted out of the body. In this regard, the debrisis captured in both the debris binand the filter before the airflowis exhausted from the body.

The cleaning rollersandcan operably connected to actuatorsand, e.g., motors, respectively. The cleaning headand the cleaning rollersandcan positioned forward of the debris bin. The cleaning rollersandcan be mounted to a housingof the cleaning headand mounted, e.g., indirectly or directly, to the bodyof the robot. For example, the cleaning rollersandcan be mounted to an underside of the bodyso that the cleaning rollersandengage debrison the floor surfaceduring the cleaning operation when the underside faces the floor surface.

The housingof the cleaning headcan be mounted to the bodyof the robot. In this way, the cleaning rollersandcan also mounted to the bodyof the robot, e.g., indirectly mounted to the bodythrough the housing. The cleaning headcan also be a removable assembly of the robotwhere the housingwith the cleaning rollersandmounted therein is removably mounted to the bodyof the robot. The housingand the cleaning rollersandcan be removable from the bodyas a unit so that the cleaning headis easily interchangeable with a replacement cleaning head.

The control system can further include a sensor system with one or more electrical sensors. The sensor system, as described herein, can generate a signal indicative of a current location of the robot, and can generate signals indicative of locations of the robotas the robottravels along the floor surface.

Cliff sensors(shown in) can be located along a bottom portion of the housing. Each of the cliff sensorscan be an optical sensor that can be configured to detect a presence or absence of an object below the optical sensor, such as the floor surface. The cliff sensorscan be connected to the controller. A bumpercan be removably secured to the bodyand can be movable relative to bodywhile mounted thereto. In some examples, the bumperform part of the body. The bump sensorsand(the bump sensors) can be connected to the bodyand engageable or configured to interact with the bumper. The bump sensorscan include break beam sensors, capacitive sensors, switches, or other sensors that can detect contact between the robot, i.e., the bumper, and objects in the environment. The bump sensorscan be in communication with the controller.

An image capture devicecan be a camera connected to the bodyand can extend through the bumperof the robot, such as through an openingof the bumper. The image capture devicecan be a camera, such as a front-facing camera, configured to generate a signal based on imagery of the environmentof the robotas the robotmoves about the floor surface. The image capture devicecan transmit the signal to the controllerfor use for navigation and cleaning routines.

Obstacle following sensors(shown in) can include an optical sensor facing outward from the bumperand that can be configured to detect the presence or the absence of an object adjacent to a side of the body. The obstacle following sensorcan emit an optical beam horizontally in a direction perpendicular (or nearly perpendicular) to the forward drive direction of the robot. The optical emitter can emit an optical beam outward from the robot, e.g., outward in a horizontal direction, and the optical detector detects a reflection of the optical beam that reflects off an object near the robot. The robot, e.g., using the controller, can determine a time of flight of the optical beam and thereby determine a distance between the optical detector and the object, and hence a distance between the robotand the object.

A side brushcan be connected to an underside of the robotand can be connected to a motoroperable to rotate the side brushwith respect to the bodyof the robot. The side brushcan be configured to engage debris to move the debris toward the cleaning assemblyor away from edges of the environment. The motorconfigured to drive the side brushcan be in communication with the controller. The brushcan rotate about a non-horizontal axis, e.g., an axis forming an angle between 75 degrees and 90 degrees with the floor surface. The non-horizontal axis, for example, can form an angle between 75 degrees and 90 degrees with the longitudinal axesandof the rollersand

The brushcan be a side brush laterally offset from a center of the robotsuch that the brushcan extend beyond an outer perimeter of the bodyof the robot. Similarly, the brushcan also be forwardly offset of a center of the robotsuch that the brushalso extends beyond the bumper. Optionally, the robotcan include multiple side brushes, such as one located on each side of the body, such as in line with drive wheelsand, respectively. The robotcan also include a button(or interface) that can be a user-operable interface configured to provide commands to the robot, such as to pause a mission, power on, power off, or return to a docking station.

In operation of some examples, the robotcan be propelled in a forward drive direction or a rearward drive direction. The robotcan also be propelled such that the robotturns in place or turns while moving in the forward drive direction or the rearward drive direction.

When the controllercauses the robotto perform a mission, the controllercan operate the motorsto drive the drive wheelsand propel the robotalong the floor surface. In addition, the controllercan operate the motorsto cause the rollersandto rotate, can operate the motorto cause the brushto rotate, and can operate the motor of the vacuum systemto generate airflow. The controllercan execute software stored on the memoryto cause the robotto perform various navigational and cleaning behaviors by operating the various motors of the robot.

The various sensors of the robotcan be used to help the robot navigate and clean within the environment. For example, the cliff sensorscan detect obstacles such as drop-offs and cliffs below portions of the robotwhere the cliff sensorsare disposed. The cliff sensorscan transmit signals to the controllerso that the controllercan redirect the robotbased on signals from the cliff sensors.

In some examples, a bump sensorcan be used to detect movement of the bumperalong a fore-aft axis of the robot. A bump sensorcan also be used to detect movement of the bumperalong one or more sides of the robot. The bump sensorscan transmit signals to the controllerso that the controllercan redirect the robotbased on signals from the bump sensors.

The image capture devicecan be configured to generate a signal based on imagery of the environmentof the robotas the robotmoves about the floor surface. The image capture devicecan transmit such a signal to the controller. The image capture devicecan be angled in an upward direction, e.g., angled between 5 degrees and 45 degrees from the floor surfaceabout which the robotnavigates. The image capture device, when angled upward, can capture images of wall surfaces of the environment so that features corresponding to objects on the wall surfaces can be used for localization.

In some examples, the obstacle following sensorscan detect detectable objects, including obstacles such as furniture, walls, persons, and other objects in the environment of the robot. In some implementations, the sensor system can include an obstacle following sensor along a side surface, and the obstacle following sensor can detect the presence or the absence an object adjacent to the side surface. The one or more obstacle following sensorscan also serve as obstacle detection sensors, similar to the proximity sensors described herein.

The robotcan also include sensors for tracking a distance travelled by the robot. For example, the sensor system can include encoders associated with the motorsfor the drive wheels, and the encoders can track a distance that the robothas travelled. In some implementations, the sensor can include an optical sensor facing downward toward a floor surface. The optical sensor can be positioned to direct light through a bottom surface of the robottoward the floor surface. The optical sensor can detect reflections of the light and can detect a distance travelled by the robotbased on changes in floor features as the robottravels along the floor surface.

The controllercan use data collected by the sensors of the sensor system to control navigational behaviors of the robotduring the mission. For example, the controllercan use the sensor data collected by obstacle detection sensors of the robot, (the cliff sensors, the bump sensors, and the image capture device) to enable the robotto avoid obstacles within the environment of the robotduring the mission.

The sensor data can also be used by the controllerfor simultaneous localization and mapping (SLAM) techniques in which the controllerextracts features of the environment represented by the sensor data and constructs a map of the floor surfaceof the environment. The sensor data collected by the image capture devicecan be used for techniques such as vision-based SLAM (VSLAM) in which the controllerextracts visual features corresponding to objects in the environmentand constructs the map using these visual features. As the controllerdirects the robotabout the floor surfaceduring the mission, the controllercan use SLAM techniques to determine a location of the robotwithin the map by detecting features represented in collected sensor data and comparing the features to previously stored features. The map formed from the sensor data can indicate locations of traversable and non-traversable space within the environment. For example, locations of obstacles can be indicated on the map as non-traversable space, and locations of open floor space can be indicated on the map as traversable space.

The sensor data collected by any of the sensors can be stored in the memory. In addition, other data generated for the SLAM techniques, including mapping data forming the map, can be stored in the memory. These data produced during the mission can include persistent data that are produced during the mission and that are usable during further missions. In addition to storing the software for causing the robotto perform its behaviors, the memorycan store data resulting from processing of the sensor data for access by the controller. For example, the map can be a map that is usable and updateable by the controllerof the robotfrom one mission to another mission to navigate the robotabout the floor surface.

The persistent data, including the persistent map, helps to enable the robotto efficiently clean the floor surface. For example, the map enables the controllerto direct the robottoward open floor space and to avoid non-traversable space. In addition, for subsequent missions, the controllercan use the map to optimize paths taken during the missions to help plan navigation of the robotthrough the environment.

is a diagram showing a communication networkthat enables networking between the mobile robotand one or more other devices, a docking station(or any of the docking stations discussed herein), a mobile device(including a controller), a cloud computing system(including a controller), or another autonomous robot separate from the mobile robot. Using the communication network, the robot, the mobile device, the docking station, and the cloud computing systemcan communicate with one another to transmit and receive data from one another. In some examples, the robot, the docking station, or both the robotand the docking stationcan communicate with the mobile devicethrough the cloud computing system. Alternatively, or additionally, the robot, the docking station, or both the robotand the docking stationcan communicate directly with the mobile device. Various types and combinations of wireless networks (e.g., Bluetooth, radio frequency, optical based, etc.) and network architectures (e.g., wi-fi or mesh networks) can be employed by the communication network.

In some examples, the mobile devicecan be a remote device that can be linked to the cloud computing systemand can enable a user to provide inputs. The mobile devicecan include user input elements such as, for example, one or more of a touchscreen display, buttons, a microphone, a mouse, a keyboard, or other devices that respond to inputs provided by the user. The mobile devicecan also include immersive media (e.g., virtual reality or augmented reality) with which the user can interact to provide input. The mobile device, in these examples, can be a virtual reality headset or a head-mounted display.

The user can provide inputs corresponding to commands for the mobile robot. In such cases, the mobile devicecan transmit a signal to the cloud computing systemto cause the cloud computing systemto transmit a command signal to the mobile robot. In some implementations, the mobile devicecan present augmented reality images. In some implementations, the mobile devicecan be a smart phone, a laptop computer, a tablet computing device, or other mobile device.

In some examples, the communication networkcan include additional nodes. For example, nodes of the communication networkcan include additional robots. Also, nodes of the communication networkcan include network-connected devices that can generate information about the environment. Such a network-connected device can include one or more sensors, such as an acoustic sensor, an image capture system, or other sensor generating signals, to detect characteristics of the environmentfrom which features can be extracted. Network-connected devices can also include home cameras, smart sensors, or the like.

In the communication network, the wireless links can utilize various communication schemes, protocols, etc., such as, for example, Bluetooth classes, Wi-Fi, Bluetooth-low-energy, also known as BLE, 802.15.4, Worldwide Interoperability for Microwave Access (WiMAX), an infrared channel, satellite band, or the like. In some examples, wireless links can include any cellular network standards used to communicate among mobile devices, including, but not limited to, standards that qualify as 1G, 2G, 3G, 4G, 5G, or the like. The network standards, if utilized, qualify as, for example, one or more generations of mobile telecommunication standards by fulfilling a specification or standards such as the specifications maintained by International Telecommunication Union. For example, the 4G standards can correspond to the International Mobile Telecommunications Advanced (IMT-Advanced) specification. Examples of cellular network standards include AMPS, GSM, GPRS, UMTS, LTE, LTE Advanced, Mobile WiMAX, and WiMAX-Advanced. Cellular network standards can use various channel access methods, e.g., FDMA, TDMA, CDMA, or SDMA.

illustrates an isometric view of a mobile cleaning robot. The mobile cleaning robotcan be consistent with the robots discussed above.shows how the mobile cleaning robot(or any of the robots discussed above) can include a body(which can be similar to the body) and a debris bin(which can be similar to the debris bin) that can be connected to the body. The mobile cleaning robotcan also include a compactor assemblythat can be located at least partially within the bodyor at least partially within the debris bin. The compactor assemblycan be driven by an actuatorthat can be located at least partially within the bodyor the debris bin. The actuatorcan be connected to the controllerand in communication therewith. The compactor assemblycan be configured or operable to be driven by the actuatorto compact debris within (or traveling to) the debris bin. The compactor assemblyand related features are discussed in further detail below.

illustrates an isometric view of a portion of the mobile cleaning robot.illustrates an isometric view of a portion of the mobile cleaning robot.illustrates an isometric view of a portion of the mobile cleaning robot.are discussed together below. The mobile cleaning robotofcan be consistent withdiscussed above;show additional details of the mobile cleaning robot. For example,shows that the debris bincan include or define a plenumand an openingconnected to a discharge of the extractor (such as to the dischargeof the extractor). The plenumcan be or include an independent duct connected to the extractor, can be part of the debris bin, can be part of the duct connecting the extractor to the debris bin, or the like. The openingcan extend at least partially through one or more wallsof the debris bin. The one or more wallscan also at least partially define a first debris chamberand a second debris chamber(collectively referred to as debris chambers). Each of the debris chamberscan be configured to receive and store debris including compacted debris.

also shows that compactor assemblycan be located at least partially within the plenum. The compactor assemblycan be located at least partially in the plenum, at least partially within an upstream plenum or discharge duct, or at least partially within a debris bin. The compactor assemblycan be operable to compact debris from the plenum into the debris chambers. The compactor assemblycan include a piston(which can be a piston, plunger, sled, shuttle, rack, or the like) that can be located at least partially within the debris bin. The pistoncan be configured to reciprocate relative to and within the plenum. The pistoncan include a first headand a second headthat can be configured to engage debris within the plenumto compact debris into the debris chambersand, respectively. The pistoncan also include a rack(e.g., a gear rack including teeth) that can be engaged with a pinion. The pinioncan be connected to the actuator (e.g., the debris bin) such that the pinioncan be driven to rotate by the actuator to translate the pistonback and forth (e.g., reciprocate) within and relative to the plenum.

The compactor assemblycan also include a filter screenthat can be connected to the plenum(or to one or more walls). The filter screencan be located downstream of the compactor (e.g., the piston). The filter screencan include a plurality of holes, bores, or openings, such that the filter screencan separate debris from the flow stream based on size, allowing small debris to pass through the filter screenand relatively larger debris to be compacted by the piston.

The compactor assemblycan also include a shuttlethat can be located at least partially downstream of the pistonand the filter screen. The shuttlecan include a shuttle rack(e.g., a gear rack including teeth) that can be engaged with a secondary pinion. The secondary pinioncan be connected to the actuator (e.g., the debris bin) such that the secondary pinioncan be driven to rotate by the actuator to translate the shuttleback and forth (e.g., reciprocate) within and relative to the plenum.

The compactor assemblycan also include a first rollerand a second roller(collectively referred to as rollers). The rollerscan be connected to an upstream side of the shuttle. The rollerscan be individually rotatable relative to the filter screen, the shuttle, and to each other. The rollerscan be engaged with a downstream side of the filter screensuch that the rollerscan translate with the shuttleand can roll along the filter screento move debris upstream for engagement by the piston.

The compactor assemblycan also include a first brushand a second brush(collectively referred to as brushes). The brushescan be brushes including bristles or other flexible members configured to move items, such as particulate or debris. The brushescan be connected to the shuttleand configured to translate or reciprocate within and relative to the plenum. The mobile cleaning robotcan also include filter modulesand(collectively referred to as filter modules) that can include one or more filters such as a pre-filterand one or more final filters (or other filter stage). In operation, the brushescan translate with the shuttleto agitate or brush an upstream surface of the pre-filterto help keep debris moving, help limit clogging, and help evenly load the filter modules.

In operation of some examples, as shown in, the pistoncan translate laterally such that the first headextends into the first debris chambersuch as to compact or compress debris received from the extractor through the openingand into the plenumfor storage in the debris chamber. As the first headis compacting, the controller (e.g., controller) can hold the location or position of the pistonto allow debris to enter an opening in the plenumbetween the second headand the second debris chamber. After a brief pause to allow debris to collect, as shown in, the pistoncan translate away from the first debris chamberand towards the second debris chamberto compact debris into the second debris chamberusing the second head. The pistoncan continue to translate or reciprocate back and forth between the first debris chamberand the second debris chamberto compact debris into the chambers, helping to increase a storage capacity of the debris binand therefore helping to reduce a frequency at which the debris binrequires emptying by a user.

As shown in, the debris chamberscan be asymmetrically sized and shaped. In other examples, the debris chamberscan be symmetrically sized or shaped. However, in such an example where the debris chambersare asymmetrically sized, it may be desirable to operate the pistonin such a manner to load the debris chambersequally. To accomplish this, the controllercan control the actuatorto operate the pistonto move in a manner that allows for relatively even loading of the debris chambers.

For example, because the second debris chambercan have a larger volume that the first debris chamber, the controllercan pause the pistonfor a first duration when the first headis in the first debris chamberand a second duration when the second headis in the second debris chamber. When the second debris chamberis larger than the first debris chamber, the first duration can be longer than the second duration to allow for the plenumto collect more debris, relatively, between the second headand the debris chambersbefore the second debris chambermoves toward the second debris chamber. This can allow for relatively more debris to be collected in the second debris chamberthan the first debris chamber