Patent Publication Number: US-2023145869-A1

Title: Surface Wiping Tool for a Robot

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims priority to U.S. Provisional Patent Application No. 63/263,837, filed Nov. 10, 2021, the disclosure of which is incorporated by reference herein in its entirety. 
    
    
     BACKGROUND 
     As technology advances, various types of robotic devices are being created for performing a variety of functions that may assist users. Robotic devices may be used for applications involving material handling, transportation, welding, assembly, and dispensing, among others. Over time, the manner in which these robotic systems operate is becoming more intelligent, efficient, and intuitive. As robotic systems become increasingly prevalent in numerous aspects of modern life, it is desirable for robotic systems to be efficient. Therefore, a demand for efficient robotic systems has helped open up a field of innovation in actuators, movement, sensing techniques, as well as component design and assembly. 
     SUMMARY 
     Example embodiments involve a surface wiping tool for a robot. The wiping tool may include an attachment component that attaches to a portion of the robot (e.g., a robotic wrist) in an arrangement that positions a container of fluid between fingers of the robot. When the robot actuates the fingers, the container may then dispense the fluid to a wiping component (e.g., a sponge) of the tool. With the fluid applied, the robot may control the wiping component to clean a surface such as a table or a whiteboard. 
     In an embodiment, a robotic device includes one or more robotic fingers and an attachable wiping tool. The attachable wiping tool includes a wiping component, a container configured to dispense a fluid, and an attachment component coupled to the robotic device. The attachment component is configured to align the one or more robotic fingers with the container such that the one or more robotic fingers, when actuated, engage the container to cause the container to dispense the fluid to the wiping component. 
     In another embodiment, an attachable wiping tool for a robotic device includes a wiping component, a container configured to dispense a fluid, and an attachment component configured to couple to the robotic device. The attachment component is configured to align one or more robotic fingers of the robotic device with the container such that the one or more robotic fingers, when actuated, engage the container to cause the container to dispense the fluid to the wiping component. 
     In a further embodiment, a method includes causing one or more robotic fingers of a robotic device to engage a container of an attachable wiping tool which is attached to the robotic device, wherein the attachable wiping tool is attached to the robotic device by an attachment component which aligns the one or more robotic fingers with the container in order to enable the one or more robotic fingers to engage the container to cause the container to dispense a fluid to a wiping component of the attachable wiping tool. The method also includes causing the wiping component of the attachable wiping tool to wipe a surface with the fluid dispensed from the container. 
     In a further embodiment, a system is provided that includes means for causing one or more robotic fingers of a robotic device to engage a container of an attachable wiping tool which is attached to the robotic device, wherein the attachable wiping tool is attached to the robotic device by an attachment component which aligns the one or more robotic fingers with the container in order to enable the one or more robotic fingers to engage the container to cause the container to dispense a fluid to a wiping component of the attachable wiping tool. The system also includes means for causing the wiping component of the attachable wiping tool to wipe a surface with the fluid dispensed from the container. 
     The foregoing summary is illustrative only and is not intended to be in any way limiting. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features will become apparent by reference to the figures and the following detailed description and the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    illustrates a configuration of a robotic system, in accordance with example embodiments. 
         FIG.  2    illustrates a mobile robot, in accordance with example embodiments. 
         FIG.  3    illustrates an exploded view of a mobile robot, in accordance with example embodiments. 
         FIG.  4    illustrates a robotic arm, in accordance with example embodiments. 
         FIGS.  5 A- 5 D  illustrate a surface wiping tool, in accordance with example embodiments. 
         FIG.  6    illustrates robotic fingers associated with a surface wiping tool, in accordance with example embodiments. 
         FIG.  7    illustrates a tray for a robot, in accordance with example embodiments. 
         FIG.  8    is a block diagram of a method, in accordance with example embodiments. 
         FIG.  9    illustrates another surface wiping tool, in accordance with example embodiments. 
         FIG.  10    illustrates a surface wiping tool with removable sponge and detachable cloth, in accordance with example embodiments. 
         FIG.  11    illustrates a captive fastener for a surface wiping tool, in accordance with example embodiments. 
     
    
    
     DETAILED DESCRIPTION 
     Example methods, devices, and systems are described herein. It should be understood that the words “example” and “exemplary” are used herein to mean “serving as an example, instance, or illustration.” Any embodiment or feature described herein as being an “example” or “exemplary” is not necessarily to be construed as preferred or advantageous over other embodiments or features unless indicated as such. Other embodiments can be utilized, and other changes can be made, without departing from the scope of the subject matter presented herein. 
     Thus, the example embodiments described herein are not meant to be limiting. It will be readily understood that the aspects of the present disclosure, as generally described herein, and illustrated in the figures, can be arranged, substituted, combined, separated, and designed in a wide variety of different configurations. 
     Throughout this description, the articles “a” or “an” are used to introduce elements of the example embodiments. Any reference to “a” or “an” refers to “at least one,” and any reference to “the” refers to “the at least one,” unless otherwise specified, or unless the context clearly dictates otherwise. The intent of using the conjunction “or” within a described list of at least two terms is to indicate any of the listed terms or any combination of the listed terms. 
     The use of ordinal numbers such as “first,” “second,” “third” and so on is to distinguish respective elements rather than to denote a particular order of those elements. For purpose of this description, the terms “multiple” and “a plurality of” refer to “two or more” or “more than one.” 
     Further, unless context suggests otherwise, the features illustrated in each of the figures may be used in combination with one another. Thus, the figures should be generally viewed as component aspects of one or more overall embodiments, with the understanding that not all illustrated features are necessary for each embodiment. In the figures, similar symbols typically identify similar components, unless context dictates otherwise. Further, unless otherwise noted, figures are not drawn to scale and are used for illustrative purposes only. Moreover, the figures are representational only and not all components are shown. For example, additional structural or restraining components might not be shown. 
     Additionally, any enumeration of elements, blocks, or steps in this specification or the claims is for purposes of clarity. Thus, such enumeration should not be interpreted to require or imply that these elements, blocks, or steps adhere to a particular arrangement or are carried out in a particular order. 
     I. Overview 
     A robotic device may be configured to perform various tasks in an environment, such as a residential environment, an office space, or a factory. In some examples, the tasks may include cleaning one or more surfaces in the environment, such as a table top or a white board. In order to facilitate robotic cleaning of such surfaces, an integrated liquid dispensing tool (also referred to as an attachable wiping tool) is disclosed herein. The tool may facilitate precise surface cleaning while leveraging existing robotic end-of-arm instructure. 
     More specifically, a robotic device may be equipped with one or more robotic fingers as part of an end-of-arm gripper. The gripper and finger(s) may be leveraged to engage a container of fluid (e.g., a cleaning fluid or water) to cause the container to dispense the fluid for cleaning a surface. The wiping tool may include an attachment component which fixedly attaches the tool to the robot. For instance, a mounting bracket may be coupled to a wrist of the robot to attach the tool to the robot. When the tool is attached by the attachment component, the fluid container may be positioned to enable contact by one or more fingers of the robot&#39;s gripper. For instance, the container may be positioned between opposable fingers of an end-of-arm gripper so that when the fingers are actuated, they contact the container and cause the container to dispense the fluid. 
     When the fluid is dispensed by the container, the fluid may be provided to a wiping component, such as a sponge, to wipe a surface. In examples where a sponge is used, the sponge may be replaceable (e.g., removable from the wiping component via a sliding motion). In some examples, the fluid may be provided to the back of the wiping component at one or more points in order to saturate the wiping component. In other examples, the wiping component may include a cut-out portion to allow the fluid to be applied through the wiping component directly to the surface. In some examples, a tubing attached to the container may connect with at least one hose which transports the fluid to the wiping component. Such examples may facilitate removing and replacing of an empty container. 
     Further examples and variations of an attachable wiping tool for a robot are discussed in reference to the Figures of this application. In addition, methods for improving robotic operation in the context of using the attachable wiping tool and/or performing cleaning tasks or other types of robot tasks are described as well. 
     II. Example Robotic Systems 
       FIG.  1    illustrates an example configuration of a robotic system that may be used in connection with the implementations described herein. Robotic system  100  may be configured to operate autonomously, semi-autonomously, or using directions provided by user(s). Robotic system  100  may be implemented in various forms, such as a robotic arm, industrial robot, or some other arrangement. Some example implementations involve a robotic system  100  engineered to be low cost at scale and designed to support a variety of tasks. Robotic system  100  may be designed to be capable of operating around people. Robotic system  100  may also be optimized for machine learning. Throughout this description, robotic system  100  may also be referred to as a robot, robotic device, or mobile robot, among other designations. 
     As shown in  FIG.  1   , robotic system  100  may include processor(s)  102 , data storage  104 , and controller(s)  108 , which together may be part of control system  118 . Robotic system  100  may also include sensor(s)  112 , power source(s)  114 , mechanical components  110 , and electrical components  116 . Nonetheless, robotic system  100  is shown for illustrative purposes, and may include more or fewer components. The various components of robotic system  100  may be connected in any manner, including wired or wireless connections. Further, in some examples, components of robotic system  100  may be distributed among multiple physical entities rather than a single physical entity. Other example illustrations of robotic system  100  may exist as well. 
     Processor(s)  102  may operate as one or more general-purpose hardware processors or special purpose hardware processors (e.g., digital signal processors, application specific integrated circuits, etc.). Processor(s)  102  may be configured to execute computer-readable program instructions  106 , and manipulate data  107 , both of which are stored in data storage  104 . Processor(s)  102  may also directly or indirectly interact with other components of robotic system  100 , such as sensor(s)  112 , power source(s)  114 , mechanical components  110 , or electrical components  116 . 
     Data storage  104  may be one or more types of hardware memory. For example, data storage  104  may include or take the form of one or more computer-readable storage media that can be read or accessed by processor(s)  102 . The one or more computer-readable storage media can include volatile or non-volatile storage components, such as optical, magnetic, organic, or another type of memory or storage, which can be integrated in whole or in part with processor(s)  102 . In some implementations, data storage  104  can be a single physical device. In other implementations, data storage  104  can be implemented using two or more physical devices, which may communicate with one another via wired or wireless communication. As noted previously, data storage  104  may include the computer-readable program instructions  106  and data  107 . Data  107  may be any type of data, such as configuration data, sensor data, or diagnostic data, among other possibilities. 
     Controller  108  may include one or more electrical circuits, units of digital logic, computer chips, or microprocessors that are configured to (perhaps among other tasks), interface between any combination of mechanical components  110 , sensor(s)  112 , power source(s)  114 , electrical components  116 , control system  118 , or a user of robotic system  100 . In some implementations, controller  108  may be a purpose-built embedded device for performing specific operations with one or more subsystems of the robotic system  100 . 
     Control system  118  may monitor and physically change the operating conditions of robotic system  100 . In doing so, control system  118  may serve as a link between portions of robotic system  100 , such as between mechanical components  110  or electrical components  116 . In some instances, control system  118  may serve as an interface between robotic system  100  and another computing device. Further, control system  118  may serve as an interface between robotic system  100  and a user. In some instances, control system  118  may include various components for communicating with robotic system  100 , including a joystick, buttons, or ports, etc. The example interfaces and communications noted above may be implemented via a wired or wireless connection, or both. Control system  118  may perform other operations for robotic system  100  as well. 
     During operation, control system  118  may communicate with other systems of robotic system  100  via wired or wireless connections, and may further be configured to communicate with one or more users of the robot. As one possible illustration, control system  118  may receive an input (e.g., from a user or from another robot) indicating an instruction to perform a requested task, such as to pick up and move an object from one location to another location. Based on this input, control system  118  may perform operations to cause the robotic system  100  to make a sequence of movements to perform the requested task. As another illustration, a control system may receive an input indicating an instruction to move to a requested location. In response, control system  118  (perhaps with the assistance of other components or systems) may determine a direction and speed to move robotic system  100  through an environment en route to the requested location. 
     Operations of control system  118  may be carried out by processor(s)  102 . Alternatively, these operations may be carried out by controller(s)  108 , or a combination of processor(s)  102  and controller(s)  108 . In some implementations, control system  118  may partially or wholly reside on a device other than robotic system  100 , and therefore may at least in part control robotic system  100  remotely. 
     Mechanical components  110  represent hardware of robotic system  100  that may enable robotic system  100  to perform physical operations. As a few examples, robotic system  100  may include one or more physical members, such as an arm, an end effector, a head, a neck, a torso, a base, and wheels. The physical members or other parts of robotic system  100  may further include actuators arranged to move the physical members in relation to one another. Robotic system  100  may also include one or more structured bodies for housing control system  118  or other components, and may further include other types of mechanical components. The particular mechanical components  110  used in a given robot may vary based on the design of the robot, and may also be based on the operations or tasks the robot may be configured to perform. 
     In some examples, mechanical components  110  may include one or more removable components. Robotic system  100  may be configured to add or remove such removable components, which may involve assistance from a user or another robot. For example, robotic system  100  may be configured with removable end effectors or digits that can be replaced or changed as needed or desired. In some implementations, robotic system  100  may include one or more removable or replaceable battery units, control systems, power systems, bumpers, or sensors. Other types of removable components may be included within some implementations. 
     Robotic system  100  may include sensor(s)  112  arranged to sense aspects of robotic system  100 . Sensor(s)  112  may include one or more force sensors, torque sensors, velocity sensors, acceleration sensors, position sensors, proximity sensors, motion sensors, location sensors, load sensors, temperature sensors, touch sensors, depth sensors, ultrasonic range sensors, infrared sensors, object sensors, or cameras, among other possibilities. Within some examples, robotic system  100  may be configured to receive sensor data from sensors that are physically separated from the robot (e.g., sensors that are positioned on other robots or located within the environment in which the robot is operating). 
     Sensor(s)  112  may provide sensor data to processor(s)  102  (perhaps by way of data  107 ) to allow for interaction of robotic system  100  with its environment, as well as monitoring of the operation of robotic system  100 . The sensor data may be used in evaluation of various factors for activation, movement, and deactivation of mechanical components  110  and electrical components  116  by control system  118 . For example, sensor(s)  112  may capture data corresponding to the terrain of the environment or location of nearby objects, which may assist with environment recognition and navigation. 
     In some examples, sensor(s)  112  may include RADAR (e.g., for long-range object detection, distance determination, or speed determination), LIDAR (e.g., for short-range object detection, distance determination, or speed determination), SONAR (e.g., for underwater object detection, distance determination, or speed determination), VICON® (e.g., for motion capture), one or more cameras (e.g., stereoscopic cameras for 3D vision), a global positioning system (GPS) transceiver, or other sensors for capturing information of the environment in which robotic system  100  is operating. Sensor(s)  112  may monitor the environment in real time, and detect obstacles, elements of the terrain, weather conditions, temperature, or other aspects of the environment. In another example, sensor(s)  112  may capture data corresponding to one or more characteristics of a target or identified object, such as a size, shape, profile, structure, or orientation of the object. 
     Further, robotic system  100  may include sensor(s)  112  configured to receive information indicative of the state of robotic system  100 , including sensor(s)  112  that may monitor the state of the various components of robotic system  100 . Sensor(s)  112  may measure activity of systems of robotic system  100  and receive information based on the operation of the various features of robotic system  100 , such as the operation of an extendable arm, an end effector, or other mechanical or electrical features of robotic system  100 . The data provided by sensor(s)  112  may enable control system  118  to determine errors in operation as well as monitor overall operation of components of robotic system  100 . 
     As an example, robotic system  100  may use force/torque sensors to measure load on various components of robotic system  100 . In some implementations, robotic system  100  may include one or more force/torque sensors on an arm or end effector to measure the load on the actuators that move one or more members of the arm or end effector. In some examples, the robotic system  100  may include a force/torque sensor at or near the wrist or end effector, but not at or near other joints of a robotic arm. In further examples, robotic system  100  may use one or more position sensors to sense the position of the actuators of the robotic system. For instance, such position sensors may sense states of extension, retraction, positioning, or rotation of the actuators on an arm or end effector. 
     As another example, sensor(s)  112  may include one or more velocity or acceleration sensors. For instance, sensor(s)  112  may include an inertial measurement unit (IMU). The IMU may sense velocity and acceleration in the world frame, with respect to the gravity vector. The velocity and acceleration sensed by the IMU may then be translated to that of robotic system  100  based on the location of the IMU in robotic system  100  and the kinematics of robotic system  100 . 
     Robotic system  100  may include other types of sensors not explicitly discussed herein. Additionally or alternatively, the robotic system may use particular sensors for purposes not enumerated herein. 
     Robotic system  100  may also include one or more power source(s)  114  configured to supply power to various components of robotic system  100 . Among other possible power systems, robotic system  100  may include a hydraulic system, electrical system, batteries, or other types of power systems. As an example illustration, robotic system  100  may include one or more batteries configured to provide charge to components of robotic system  100 . Some of mechanical components  110  or electrical components  116  may each connect to a different power source, may be powered by the same power source, or be powered by multiple power sources. 
     Any type of power source may be used to power robotic system  100 , such as electrical power or a gasoline engine. Additionally or alternatively, robotic system  100  may include a hydraulic system configured to provide power to mechanical components  110  using fluid power. Components of robotic system  100  may operate based on hydraulic fluid being transmitted throughout the hydraulic system to various hydraulic motors and hydraulic cylinders, for example. The hydraulic system may transfer hydraulic power by way of pressurized hydraulic fluid through tubes, flexible hoses, or other links between components of robotic system  100 . Power source(s)  114  may charge using various types of charging, such as wired connections to an outside power source, wireless charging, combustion, or other examples. 
     Electrical components  116  may include various mechanisms capable of processing, transferring, or providing electrical charge or electric signals. Among possible examples, electrical components  116  may include electrical wires, circuitry, or wireless communication transmitters and receivers to enable operations of robotic system  100 . Electrical components  116  may interwork with mechanical components  110  to enable robotic system  100  to perform various operations. Electrical components  116  may be configured to provide power from power source(s)  114  to the various mechanical components  110 , for example. Further, robotic system  100  may include electric motors. Other examples of electrical components  116  may exist as well. 
     Robotic system  100  may include a body, which may connect to or house appendages and components of the robotic system. As such, the structure of the body may vary within examples and may further depend on particular operations that a given robot may have been designed to perform. For example, a robot developed to carry heavy loads may have a wide body that enables placement of the load. Similarly, a robot designed to operate in tight spaces may have a relatively tall, narrow body. Further, the body or the other components may be developed using various types of materials, such as metals or plastics. Within other examples, a robot may have a body with a different structure or made of various types of materials. 
     The body or the other components may include or carry sensor(s)  112 . These sensors may be positioned in various locations on the robotic system  100 , such as on a body, a head, a neck, a base, a torso, an arm, or an end effector, among other examples. 
     Robotic system  100  may be configured to carry a load, such as a type of cargo that is to be transported. In some examples, the load may be placed by the robotic system  100  into a bin or other container attached to the robotic system  100 . The load may also represent external batteries or other types of power sources (e.g., solar panels) that the robotic system  100  may utilize. Carrying the load represents one example use for which the robotic system  100  may be configured, but the robotic system  100  may be configured to perform other operations as well. 
     As noted above, robotic system  100  may include various types of appendages, wheels, end effectors, gripping devices and so on. In some examples, robotic system  100  may include a mobile base with wheels, treads, or some other form of locomotion. Additionally, robotic system  100  may include a robotic arm or some other form of robotic manipulator. In the case of a mobile base, the base may be considered as one of mechanical components  110  and may include wheels, powered by one or more of actuators, which allow for mobility of a robotic arm in addition to the rest of the body. 
       FIG.  2    illustrates a mobile robot, in accordance with example embodiments.  FIG.  3    illustrates an exploded view of the mobile robot, in accordance with example embodiments. More specifically, a robot  200  may include a mobile base  202 , a midsection  204 , an arm  206 , an end-of-arm system (EOAS)  208 , a mast  210 , a perception housing  212 , and a perception suite  214 . The robot  200  may also include a compute box  216  stored within mobile base  202 . 
     The mobile base  202  includes two drive wheels positioned at a front end of the robot  200  in order to provide locomotion to robot  200 . The mobile base  202  also includes additional casters (not shown) to facilitate motion of the mobile base  202  over a ground surface. The mobile base  202  may have a modular architecture that allows compute box  216  to be easily removed. Compute box  216  may serve as a removable control system for robot  200  (rather than a mechanically integrated control system). After removing external shells, the compute box  216  can be easily removed and/or replaced. The mobile base  202  may also be designed to allow for additional modularity. For example, the mobile base  202  may also be designed so that a power system, a battery, and/or external bumpers can all be easily removed and/or replaced. 
     The midsection  204  may be attached to the mobile base  202  at a front end of the mobile base  202 . The midsection  204  includes a mounting column which is fixed to the mobile base  202 . The midsection  204  additionally includes a rotational joint for arm  206 . More specifically, the midsection  204  includes the first two degrees of freedom for arm  206  (a shoulder yaw J 0  joint and a shoulder pitch J 1  joint). The mounting column and the shoulder yaw J 0  joint may form a portion of a stacked tower at the front of mobile base  202 . The mounting column and the shoulder yaw J 0  joint may be coaxial. The length of the mounting column of midsection  204  may be chosen to provide the arm  206  with sufficient height to perform manipulation tasks at commonly encountered height levels (e.g., coffee table top and counter top levels). The length of the mounting column of midsection  204  may also allow the shoulder pitch J 1  joint to rotate the arm  206  over the mobile base  202  without contacting the mobile base  202 . 
     The arm  206  may be a  7 DOF robotic arm when connected to the midsection  204 . As noted, the first two DOFs of the arm  206  may be included in the midsection  204 . The remaining five DOFs may be included in a standalone section of the arm  206  as illustrated in  FIGS.  2    and  3 . The arm  206  may be made up of plastic monolithic link structures. Inside the arm  206  may be housed standalone actuator modules, local motor drivers, and thru bore cabling. 
     The EOAS  208  may be an end effector at the end of arm  206 . EOAS  208  may allow the robot  200  to manipulate objects in the environment. As shown in  FIGS.  2  and  3   , EOAS  208  may be a gripper, such as an underactuated pinch gripper. The gripper may include one or more contact sensors such as force/torque sensors and/or non-contact sensors such as one or more cameras to facilitate object detection and gripper control. EOAS  208  may also be a different type of gripper such as a suction gripper or a different type of tool such as a drill or a brush. EOAS  208  may also be swappable or include swappable components such as gripper digits. 
     The mast  210  may be a relatively long, narrow component between the shoulder yaw J 0  joint for arm  206  and perception housing  212 . The mast  210  may be part of the stacked tower at the front of mobile base  202 . The mast  210  may be fixed relative to the mobile base  202 . The mast  210  may be coaxial with the midsection  204 . The length of the mast  210  may facilitate perception by perception suite  214  of objects being manipulated by EOAS  208 . The mast  210  may have a length such that when the shoulder pitch J 1  joint is rotated vertical up, a topmost point of a bicep of the arm  206  is approximately aligned with a top of the mast  210 . The length of the mast  210  may then be sufficient to prevent a collision between the perception housing  212  and the arm  206  when the shoulder pitch J 1  joint is rotated vertical up. 
     As shown in  FIGS.  2  and  3   , the mast  210  may include a 3D lidar sensor configured to collect depth information about the environment. The 3D lidar sensor may be coupled to a carved-out portion of the mast  210  and fixed at a downward angle. The lidar position may be optimized for localization, navigation, and for front cliff detection. 
     The perception housing  212  may include at least one sensor making up perception suite  214 . The perception housing  212  may be connected to a pan/tilt control to allow for reorienting of the perception housing  212  (e.g., to view objects being manipulated by EOAS  208 ). The perception housing  212  may be a part of the stacked tower fixed to the mobile base  202 . A rear portion of the perception housing  212  may be coaxial with the mast  210 . 
     The perception suite  214  may include a suite of sensors configured to collect sensor data representative of the environment of the robot  200 . The perception suite  214  may include an infrared(IR)-assisted stereo depth sensor. The perception suite  214  may additionally include a wide-angled red-green-blue (RGB) camera for human-robot interaction and context information. The perception suite  214  may additionally include a high resolution RGB camera for object classification. A face light ring surrounding the perception suite  214  may also be included for improved human-robot interaction and scene illumination. In some examples, the perception suite  214  may also include a projector configured to project images and/or video into the environment. 
       FIG.  4    illustrates a robotic arm, in accordance with example embodiments. The robotic arm includes  7  DOFs: a shoulder yaw J 0  joint, a shoulder pitch J 1  joint, a bicep roll J 2  joint, an elbow pitch J 3  joint, a forearm roll J 4  joint, a wrist pitch J 5  joint, and wrist roll J 6  joint. Each of the joints may be coupled to one or more actuators. The actuators coupled to the joints may be operable to cause movement of links down the kinematic chain (as well as any end effector attached to the robot arm). 
     The shoulder yaw J 0  joint allows the robot arm to rotate toward the front and toward the back of the robot. One beneficial use of this motion is to allow the robot to pick up an object in front of the robot and quickly place the object on the rear section of the robot (as well as the reverse motion). Another beneficial use of this motion is to quickly move the robot arm from a stowed configuration behind the robot to an active position in front of the robot (as well as the reverse motion). 
     The shoulder pitch J 1  joint allows the robot to lift the robot arm (e.g., so that the bicep is up to perception suite level on the robot) and to lower the robot arm (e.g., so that the bicep is just above the mobile base). This motion is beneficial to allow the robot to efficiently perform manipulation operations (e.g., top grasps and side grasps) at different target height levels in the environment. For instance, the shoulder pitch J 1  joint may be rotated to a vertical up position to allow the robot to easily manipulate objects on a table in the environment. The shoulder pitch J 1  joint may be rotated to a vertical down position to allow the robot to easily manipulate objects on a ground surface in the environment. 
     The bicep roll J 2  joint allows the robot to rotate the bicep to move the elbow and forearm relative to the bicep. This motion may be particularly beneficial for facilitating a clear view of the EOAS by the robot&#39;s perception suite. By rotating the bicep roll J 2  joint, the robot may kick out the elbow and forearm to improve line of sight to an object held in a gripper of the robot. 
     Moving down the kinematic chain, alternating pitch and roll joints (a shoulder pitch J 1  joint, a bicep roll J 2  joint, an elbow pitch J 3  joint, a forearm roll J 4  joint, a wrist pitch J 5  joint, and wrist roll J 6  joint) are provided to improve the manipulability of the robotic arm. The axes of the wrist pitch J 5  joint, the wrist roll J 6  joint, and the forearm roll J 4  joint are intersecting for reduced arm motion to reorient objects. The wrist roll J 6  point is provided instead of two pitch joints in the wrist in order to improve object rotation. 
     In some examples, a robotic arm such as the one illustrated in  FIG.  4    may be capable of operating in a teach mode. In particular, teach mode may be an operating mode of the robotic arm that allows a user to physically interact with and guide robotic arm towards carrying out and recording various movements. In a teaching mode, an external force is applied (e.g., by the user) to the robotic arm based on a teaching input that is intended to teach the robot regarding how to carry out a specific task. The robotic arm may thus obtain data regarding how to carry out the specific task based on instructions and guidance from the user. Such data may relate to a plurality of configurations of mechanical components, joint position data, velocity data, acceleration data, torque data, force data, and power data, among other possibilities. 
     During teach mode the user may grasp onto the EOAS or wrist in some examples or onto any part of robotic arm in other examples, and provide an external force by physically moving robotic arm. In particular, the user may guide the robotic arm towards grasping onto an object and then moving the object from a first location to a second location. As the user guides the robotic arm during teach mode, the robot may obtain and record data related to the movement such that the robotic arm may be configured to independently carry out the task at a future time during independent operation (e.g., when the robotic arm operates independently outside of teach mode). In some examples, external forces may also be applied by other entities in the physical workspace such as by other objects, machines, or robotic systems, among other possibilities. 
     III. Example Surface Wiping Tools 
       FIGS.  5 A- 5 D  show an attachable wiping tool for a robotic device, in accordance with example embodiments. More specifically,  FIG.  5 A  illustrates an attachable wiping tool  500  attached to a robotic device  520 . The attachable wiping tool  500  includes an attachment component  502  coupled to a wrist  522  of the robotic device  520 . The wrist  522  may be operable to rotate the end effector of the robotic device  520 . In this case, the end effector includes two opposable robotic fingers  524 . The fingers  524  may be customized to interface with the attachable wiping tool  500 . 
     In the illustrated example, the attachable component  502  is a mounting bracket which holds a fluid container  504  in position relative to the two opposable fingers  524  of the robotic device  520 . Accordingly, when the robotic device  520  actuates the opposable fingers  524  to rotate inward, the fingers  524  will engage with the fluid container  504 . As pressure is applied to the fluid container  504 , fluid may be dispensed to the wiping component  506  of the attachable wiping tool  500 . In the illustrated example, the wiping component  506  includes a tube and sponge oriented perpendicular to the fluid container  504 . In some examples, the tube of the wiping component may further include one or more circular internal support stiffeners. Fluid may be applied to the back of the sponge to saturate the sponge to enable cleaning of surface  530  in environment  500 . 
       FIGS.  5 B,  5 C, and  5 D  illustrate additional views of the attachable wiping tool  500 . More specifically,  FIG.  5 B  provides an isometric view,  FIG.  5 C  provides a side view, and  FIG.  5 D  provides a top down view. In each view of the attachable wiping tool  500 , the attachment component  502 , the fluid container  504 , and the wiping component  506  are displayed. The attachable wiping component  500  additionally includes a screw on lid  508  to hold the container  504 . More specifically, the container  504  may take the form of a removable bottle (e.g., a soft plastic bottle) which may be removed and refilled or replaced via the screw on lid  508 . In further examples, the lid  508  may instead include a snap in connection to hold the container  504 . 
     In order for the container  504  to dispense the fluid to the wiping component  506 , the container  504  may include a tubing  510  which attaches to one or more hoses of the attachable wiping tool  500 . The one or more hoses may distribute the fluid to the back of the wiping component  506  (e.g., to saturate a sponge for surface cleaning). In some examples, the attachable wiping tool  500  may include two or more such hoses. A splitter may be provided to divide fluid among each of the hoses. Each hose may then distribute the fluid to a different portion of the wiping component  506 . For instance, each hose may provide fluid to a different portion of a sponge of the wiping component  506 . In further examples, the wiping component  506  may include multiple sponges, and each hose may provide fluid to a different sponge of the wiping component  506 . 
     As noted, the wiping component  506  of the attachable wiping tool  500  may generally be positioned perpendicular to the container  504 . In some examples, the attachable wiping tool  500  may include one or more hardstops to maintain the wiping component within a certain threshold from a perpendicular orientation to the container. The hardstop(s) may be configured to limit rotation of the wiping component, keep the wiping component centered, and/or keep the wiping component within a bounding box. In further examples, the hardstop(s) may act as a clutch to allow slippage before the wiping component  506  completely breaks off. 
     In further examples, the wiping component  506  may comprise a different material and/or form factor. In some such examples, the wiping component  506  may include a stiff rubber support backing to act as a squeegee. In further examples, the wiping component  506  may include a rubber strip in combination with another material, such as a sponge. 
       FIG.  6    illustrates robotic fingers associated with a surface wiping tool, in accordance with example embodiments. More specifically, different types of robotic fingers may be used in conjunction with a surface wiping tool. In some examples, a robotic gripper may include interchangeable digits. In such examples, a particular set of digits may be attached to the gripper specifically to interface with the fluid container of a surface wiping tool. The particular set of digits may be designed to apply an increased amount of force to the fluid container in comparison to a set of digits typically used by the robot. 
     In reference to  FIG.  6   , a robotic gripper  600  may include digits  602  and  604 . In some examples, a typical digit used by the robotic device may be an underactuated digit with unactuated joints to allow for conforming to objects, such as illustrated by digit  602 . When the digits are actuated with a surface wiping tool attached to the robot, pressure may be applied to a fluid container  650  from at least three directions  612 ,  614 , and  616 . More specifically, while a finite amount of force can be applied to the container  650  via gripper finger torque alone, additional reactionary normal force can be applied opposite to the fingers by securing the container  650  from moving within the surface wiping tool. The direction of the reactionary normal force is illustrated by arrow  616 . 
     In some examples, one or more digits may be designed specifically for use with a particular container size and associated surface wiping tool. More specifically, a shorter digit  606  may be used to apply greater force to the container  650 . Two digits with the form factor illustrated by digit  606  may be used to apply increased force to the container  650  in comparison to, e.g., digits of the form factor illustrated by digit  602 . In some examples, a pair of digits having the form factor illustrated by digit  606  may be interchangeable digits which can be attached to the gripper  600  specifically for operating the surface wiping tool. As illustrated in  FIG.  6   , digits of the form factor illustrated by digit  606  may be configured to be attached to the same dovetail component of the gripper as digits of the form factor illustrated by digit  602 . 
       FIG.  7    illustrates a tray for a robot, in accordance with example embodiments. More specifically, a robot  700  may be equipped with a tray  702  for collecting debris, including debris that may be collected while employing a surface wiping tool as described herein. The robot  700  may be configured with a form factor that allows for positioning of the tray underneath surfaces in the environment, such as table tops. The robot  700  may then easily sweep debris from the surfaces into the tray  702 . In some examples, the tray  702  may be removable to facilitate emptying of the tray  702 . More specifically, the tray  702  may be connected to the base of the robot  700  via a sliding connection to allow a user to slide out the tray  702  and empty the tray  702 . 
     In further examples, a removable tray may also take on the form factor illustrated by tray  704  as well. A captured plate mechanism may be used to slide the tray on and off without requiring any additional tools. In reference to  FIG.  7   , the dark colored plates of tray  704  are designed to be attached to the robot base while the light colored plates of tray  704  are designed to be attached to the tray  704  itself. 
       FIG.  9    illustrates another surface wiping tool, in accordance with example embodiments. More specifically, surface wiping tool  902  may be similar to the surface wiping tool described in reference to  FIGS.  5 A- 5 D . Surface wiping tool  904  illustrates an alternative form factor with increased length. Surface wiping tool  904  may operate similarly as surface wiping tool  902  in allowing fluid to reach the sponge from the fluid container through operation of robotic fingers. Surface wiping tool  904  may provide improved flexibility for a robotic device in allowing the robotic device to reach surfaces in the environment for wiping. 
       FIG.  10    illustrates a surface wiping tool with removable sponge and detachable cloth, in accordance with example embodiments. More specifically, the sponge  1002  may be an off-the-shelf sponge capable of sliding on and off of the surface wiping tool  1000 . Removable sponge  1002  may generally be easy to manufacture and attach to or detach from the surface wiping tool  1000 . In further examples, a less thick sponge may be used in order to absorb less fluid to avoid putting excessive torque on the robot. Cloth  1004  surrounding sponge  1002  may be attached to the sponge  1002  using the illustrated attachment mechanism or another suitable attachment mechanism. Cloth  1004  may be removable to allow for easy replacement of cloth  1004  after use by a robotic device. 
       FIG.  11    illustrates a captive fastener for a surface wiping tool, in accordance with example embodiments. More specifically, a surface wiping tool, such as surface wiping tool  904  from  FIG.  9   , may include a captive fastener  1100  using magnets  1102  and associated steel retaining rings  1104  around shoulder bolt thumb screws. The captive fastener  1100  may allow the surface wiping tool to be attached to the robot, but may also prevent fasteners from being separated from the tool. Each steel retaining ring  1104  is attracted to the corresponding magnet  1102 , which creates a stable retracted position that pulls the screw out of the hole, to allow for the easy removal of the surface wiping tool from the wrist of a robotic device. 
     IV. Example Methods 
       FIG.  8    is a block diagram of method  800 , in accordance with example embodiments. Blocks  802  and  804  may collectively be referred to as method  800 . In some examples, method  800  of  FIG.  8    may be carried out by a control system, such as control system  118  of robotic system  100 . In further examples, method  800  of  FIG.  8    may be carried out by a computing device or a server device remote from the robotic device. In still further examples, method  800  may be carried out by one or more processors, such as processor(s)  102 , executing program instructions, such as program instructions  106 , stored in a data storage, such as data storage  104 . Execution of method  800  may involve a robotic device, such as the robotic device illustrated and described with respect to  FIGS.  1 - 4   . Other robotic devices may also be used in the performance of method  800 . Execution of method  800  may further involve an attachable wiping tool attached to a robotic device as described herein. 
     Those skilled in the art will understand that the block diagram of  FIG.  8    illustrates functionality and operation of certain implementations of the present disclosure. In this regard, each block of the block diagram may represent a module, a segment, or a portion of program code, which includes one or more instructions executable by one or more processors for implementing specific logical functions or steps in the process. The program code may be stored on any type of computer readable medium, for example, such as a storage device including a disk or hard drive. 
     In addition, each block may represent circuitry that is wired to perform the specific logical functions in the process. Alternative implementations are included within the scope of the example implementations of the present application in which functions may be executed out of order from that shown or discussed, including substantially concurrent or in reverse order, depending on the functionality involved, as would be understood by those reasonably skilled in the art. 
     At block  802 , method  800  involves causing one or more robotic fingers of a robotic device to engage a container of an attachable wiping tool. The attachable wiping tool may be attached to the robotic device by an attachment component, for instance, a brace mounted to a wrist of the robotic device. The attachment component may align the one or more robotic fingers with the container. The attachment component may therefore enable the one or more robotic fingers to engage the container to cause the container to dispense a fluid. The fluid may be dispensed to a wiping component of the attachable wiping tool. 
     At block  804 , method  800  involves causing the wiping component of the attachable wiping tool to wipe a surface with the fluid dispensed from the container. In some examples, the fluid may first be applied to the wiping component (e.g., a sponge), which is then moved by the robot across a surface to clean the surface. In further examples, the fluid may be applied through a cutout portion of the wiping component so that the fluid is directly applied to a surface in the environment of the robot. The robot may then control the wiping component to move the wiping component across the surface in order to wipe the surface with the fluid. 
     Method  800  or other methods contemplated herein may additionally involve further control steps as well or instead. Such additional functions may be performed while cleaning surfaces of an environment with a robot. Further additional functions may be performed while performing one or more other services with a robot in the environment as well or instead. 
     A. Using Machine Learning to Identify a Broken Tool 
     In some examples, an attachable wiping tool may periodically be bumped askew, for instance, due to imprecise control of the robot in determining where to wipe. In such examples, an intervention may be added (e.g., in the form of a human operator) to determine a state of the tool (e.g., a misaligned tool, a broken tool, etc.) and correct any issues. Data from such interventions may be used to train a machine learning model such as a neural network to use image data to identify such issues with the tool. In some examples, a pretrained network from publicly available image caption data may be used as a baseline model. The baseline model may then be fine tuned using data from operations, such as interventions. After training, when the trained model indicates that a tool is askew or damaged, a robot may be configured to pause operation and raise an alert to an operator to come and fix the tool. This methodology may be applied to other types of tools as well or instead. 
     B. Using Queues to Parallelize for Speed 
     In some examples, robotic cleaning operations may be improved and made faster by using two or more independent control systems that feed into each other with queues. As an example, three independent systems may be used to control robotic operation: a head and graphics processing unit (GPU) for perception, a central processing unit (CPU) for motion planning, and an arm that can execute manipulation plans. The head and perception module may be configured to find a next section of a table or other surface and add the section to a “to wipe” list. The CPU may perform arm motion planning to find collision-free paths to wipe. The arm and base may execute these wiping plans to wipe the table or other surface. In further examples, different combinations of two or more control systems may be used with different divisions of sub-tasks. Additionally, this methodology of using independent control systems with queues may be applied to other types of robot manipulation tasks as well or instead. 
     C. Automatic Coverage Metric 
     In some examples, a robot may be configured to automatically measure its performance in performing a task such as a cleaning task and provide data about the task that the robot is performing. This data may be data from table detection perception. This process may involve full building localization to understand which parts of a surface have already been wiped if the robot comes around to wipe from the other side. The robot may understand where its wiping tool is positioned in order to obtain an understanding of which parts of surfaces have been contacted. Additionally, the robot may be configured to sense forces so that the robot can tell the difference between almost touching a surface or grazing the surface in comparison to fully wiping the surface. Performance data may be used to adjust robot behavior in real time and/or train one or more models to improve future performance. Similar methodology may be applied to other types of robot tasks besides cleaning tasks as well or instead. 
     D. Scenario Testing For Continuous Improvement 
     In some examples, examples of challenging environments (e.g., challenging types of tables for a cleaning task) may be harvested from robot logs. Updated versions of software to control robot operations (e.g., surface wiping operations) may be run on logged robot data to determine if one or more metrics of robot performance (e.g., success rate and wiping coverage) improve over time. Tools may be developed to turn a failed test into a scenario for training. Automated tests may be run on new software code to identify regressions in robot performance. This methodology may also provide information about improvements so that requirement thresholds can be increased over time as robot performance improves. This methodology may be applied to other types of robot tasks besides cleaning or surface wiping tasks as well or instead. 
     E. Multi-Robot Coordination 
     In some examples, performance of some robot tasks may depend on performance of other types of robot tasks. For example, a robot may be better able to wipe tables when the chairs around the table are pushed in all the way, but it may be easier for a robot to push in chairs if the robot is not currently equipped with an attachable wiping tool. In such a case, one robot may be controlled to navigate around the environment and note where chairs are pushed all the way in and otherwise pushing the chairs in. Tables with chairs that are fully pushed in may then be added to a work queue by the robot. One or more other robots designated as wiping robots with attached wiping tools may then be controlled to select tables in the queue and claim tables to clean. This methodology may be applied to other types of robot tasks (besides cleaning or wiping tasks) that depend upon the performance of other types of robot tasks as well or instead. 
     V. Conclusion 
     The present disclosure is not to be limited in terms of the particular embodiments described in this application, which are intended as illustrations of various aspects. Many modifications and variations can be made without departing from its spirit and scope, as will be apparent to those skilled in the art. Functionally equivalent methods and apparatuses within the scope of the disclosure, in addition to those enumerated herein, will be apparent to those skilled in the art from the foregoing descriptions. Such modifications and variations are intended to fall within the scope of the appended claims. 
     The above detailed description describes various features and functions of the disclosed systems, devices, and methods with reference to the accompanying figures. In the figures, similar symbols typically identify similar components, unless context dictates otherwise. The example embodiments described herein and in the figures are not meant to be limiting. Other embodiments can be utilized, and other changes can be made, without departing from the spirit or scope of the subject matter presented herein. It will be readily understood that the aspects of the present disclosure, as generally described herein, and illustrated in the figures, can be arranged, substituted, combined, separated, and designed in a wide variety of different configurations, all of which are explicitly contemplated herein. 
     A block that represents a processing of information may correspond to circuitry that can be configured to perform the specific logical functions of a herein-described method or technique. Alternatively or additionally, a block that represents a processing of information may correspond to a module, a segment, or a portion of program code (including related data). The program code may include one or more instructions executable by a processor for implementing specific logical functions or actions in the method or technique. The program code or related data may be stored on any type of computer readable medium such as a storage device including a disk or hard drive or other storage medium. 
     The computer readable medium may also include non-transitory computer readable media such as computer-readable media that stores data for short periods of time like register memory, processor cache, and random access memory (RAM). The computer readable media may also include non-transitory computer readable media that stores program code or data for longer periods of time, such as secondary or persistent long term storage, like read only memory (ROM), optical or magnetic disks, compact-disc read only memory (CD-ROM), for example. The computer readable media may also be any other volatile or non-volatile storage systems. A computer readable medium may be considered a computer readable storage medium, for example, or a tangible storage device. 
     Moreover, a block that represents one or more information transmissions may correspond to information transmissions between software or hardware modules in the same physical device. However, other information transmissions may be between software modules or hardware modules in different physical devices. 
     The particular arrangements shown in the figures should not be viewed as limiting. It should be understood that other embodiments can include more or less of each element shown in a given figure. Further, some of the illustrated elements can be combined or omitted. Yet further, an example embodiment can include elements that are not illustrated in the figures. 
     While various aspects and embodiments have been disclosed herein, other aspects and embodiments will be apparent to those skilled in the art. The various aspects and embodiments disclosed herein are for purposes of illustration and are not intended to be limiting, with the true scope being indicated by the following claims.