Washing Machine Appliance and Method of Operation

The present subject matter relates generally to washing machine appliances, or more specifically, to systems and methods for assessing agitation effectiveness in a washing machine appliance.

Washing machine appliances generally include a cabinet which receives a wash tub for containing water or wash fluid (e.g., water and detergent, bleach, or other wash additives). The wash tub may be suspended within the cabinet by a suspension system to allow some movement relative to the cabinet during operation. A wash basket is rotatably mounted within the wash tub and defines a wash chamber for receipt of articles for washing. A drive assembly is coupled to the wash tub and is configured to selectively rotate the wash basket within the wash tub.

Washing machine appliances are typically equipped to operate in one or more modes or cycles, such as wash, rinse, and spin cycles. For example, during a wash or rinse cycle, the wash fluid is directed into the wash tub in order to wash and/or rinse articles within the wash chamber. In addition, the wash basket and/or an agitation element can rotate to agitate or impart motion to articles within the wash chamber.

Washing machine appliances may attempt to agitate articles within the wash basket even with a wash basket that is overloaded with articles. Additionally, washing machine appliances may attempt to agitate items within the wash basket; however, operational malfunctions can impede the washing machine from achieving an intended level of agitation or prevent agitation entirely. For example, the agitation element may malfunction or the wash basket may be overloaded with articles. Further, a malfunctioning agitator or an overloaded wash basket may lead to poor cleaning performance of the articles, an uneven distribution of wash fluids, tangled or even damages articles, an extended wash cycle operation, and the like.

As such, a system and method for operating a washing machine appliance that can detect and assess agitation effectiveness would be desirable. Furthermore, a system and method for determining fault or failure of an agitation element would be advantageous.

Advantages of the invention will be set forth in part in the following description, or may be apparent from the description, or may be learned through practice of the invention.

An aspect of the present disclosure is directed to a washing machine appliance includes a wash tub and a wash basket mounted therewithin. The appliance includes a motor assembly coupled to the wash basket to rotate the wash basket. The appliance includes a camera configured by a controller to capture images of articles within the wash basket. The appliance includes the controller operably coupled to the motor assembly and the camera. The controller is configured to rotate the wash basket. The controller is configured to analyze the images to determine that the articles are rotated less than at least the set distance. The controller is configured to generate an output signal configured to alert a user based on the wash basket failing to rotate at least the set distance within the period of time.

Another aspect of the present disclosure is directed to a method of operating a washing machine appliance. The method includes rotating a wash basket a rotated distance. The method includes obtaining a plurality of images. The method includes analyzing the plurality of images to determine that articles within the wash basket are rotated less than a set distance within a period of time based on a travel distance of the articles among the captured images. The method includes generating an output signal configured to alert a user based on the wash basket failing to rotate at least the set distance within the period of time.

These and other features, aspects and advantages of the present invention will become better understood with reference to the following description and appended claims. The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.

Repeat use of reference characters in the present specification and drawings is intended to represent the same or analogous features or elements of the present invention.

Reference now will be made in detail to embodiments of the invention, one or more examples of which are illustrated in the drawings. Each example is provided by way of explanation of the invention, not limitation of the invention. In fact, it will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the scope or spirit of the invention. For instance, features illustrated or described as part of one embodiment can be used with another embodiment to yield a still further embodiment. Thus, it is intended that the present invention covers such modifications and variations as come within the scope of the appended claims and their equivalents.

As used herein, the terms “includes” and “including” are intended to be inclusive in a manner similar to the term “comprising.” Similarly, the term “or” is generally intended to be inclusive (i.e., “A or B” is intended to mean “A or B or both”). Approximating language, as used herein throughout the specification and claims, is applied to modify any quantitative representation that could permissibly vary without resulting in a change in the basic function to which it is related. Accordingly, a value modified by a term or terms, such as “about,” “generally,” “approximately,” and “substantially,” are not to be limited to the precise value specified. In at least some instances, the approximating language may correspond to the precision of an instrument for measuring the value. For example, the approximating language may refer to being within a 10 percent margin.

1 FIG. As used herein, the terms “first,” “second,” and “third” may be used interchangeably to distinguish one component from another and are not intended to signify location or importance of the individual components. Terms such as “inner” and “outer” refer to relative directions with respect to the interior and exterior of the washing machine appliance. For example, “inner” or “inward” refers to the direction towards the interior of the washing machine appliance. Terms such as “left,” “right,” “front,” “back,” “top,” or “bottom” are used with reference to the perspective of the washing machine appliance as illustrated in. For example, a user faces a front of the washing machine appliance to place articles through a top of the washing machine appliance.

1 FIG. 100 100 Referring now to the drawings,illustrates a perspective view of one embodiment of a washing machine appliancein accordance with aspects of the present subject matter. It should be appreciated that, although the washing machine applianceillustrated herein may generally correspond to any suitable washing machine appliance such as a top-loader or front-loader washing machine appliance.

1 3 FIGS.through 1 5 FIGS.through 100 With reference to, the transverse direction, denoted by the arrow labeled “T,” corresponds to the axis along which terms such as “front” and “back” are oriented. The vertical direction, indicated by the arrow labeled “V,” aligns with the axis associated with terms such as “top” and “bottom.” The lateral direction, represented by the arrow labeled “L,” defines the axis along which terms such as “left” and “right” are referenced. These directional conventions provide a standardized framework for the spatial orientation of the washing machine appliancedescribed herein and among.

It should be appreciated that where a value is at a threshold, one skilled in the art may determine whether an action at the threshold may correspond to actions below the threshold or above the threshold. For instance, an action “below a threshold” may include values “at or below a threshold”. In another instance, an action “above a threshold” may include values “at or above a threshold”. One skilled in the art may alter the corresponding action of a value at or equal to a threshold without deviating from the scope of the present disclosure.

Embodiments of a washing machine appliance, a controller for a washing machine appliance, and a method for operating a washing machine appliance are provided. Embodiments provided herein allow for detection of presence of fluid (e.g., water or water-based solution) in a washer tub. Methods provided herein allow for determination of the presence of fluid within or outside of a wash cycle without requiring utilization of a fluid level sensor (e.g., a pressure sensor or switch, a load sensor or switch, a moisture sensor or switch, etc.). Embodiments provided herein may allow for detection of fluid presence in the wash tub while utilizing a fluid sensor, allowing for failure detection of a fluid level sensor or component, such as a drain pump assembly. Embodiments provided herein also allow for sensor-less flood protection or fluid detection.

1 5 FIGS.through 1 2 FIGS.and 3 FIG. 4 5 FIGS.and 100 100 100 100 114 200 illustrate an example embodiment of a vertical axis washing machine appliance. Specifically,illustrate perspective views of washing machine appliancein a closed and an open position, respectively.provides a side cross-sectional view of washing machine appliance. Washing machine appliancegenerally defines a vertical direction V, a lateral direction L, and a transverse direction T, each of which is mutually perpendicular, such that an orthogonal coordinate system is generally defined.illustrate a top view of a wash basketcontaining articles.

100 102 104 106 108 102 110 100 112 108 3 FIG. 2 FIG. Washing machine appliancehas a cabinetthat extends between a top portionand a bottom portionalong the vertical direction V, between a first side (left) and a second side (right) along the lateral direction L, and between a front and a rear along the transverse direction T. As best shown in, a wash tubis positioned within cabinet, defines a wash chamber, and is generally configured for retaining wash fluids during an operating cycle. Washing machine appliancefurther includes a primary dispenser() for dispensing wash fluid into wash tub. The term “wash fluid” refers to a liquid used for washing and/or rinsing articles during an operating cycle and may include any combination of water, detergent, fabric softener, bleach, and other wash additives or treatments.

100 114 108 116 114 108 100 100 100 In addition, washing machine applianceincludes the wash basketthat is positioned within wash tuband generally defines an openingfor receipt of articles for washing. More specifically, wash basketis rotatably mounted within wash tubsuch that it is rotatable about an axis of rotation A. According to the illustrated embodiment, the axis of rotation A is substantially parallel to the vertical direction V. While described in the context of a specific embodiment of vertical axis washing machine appliance, it should be appreciated that vertical axis washing machine applianceis provided by way of example only. It will be understood that aspects of the present subject matter may be used in any other suitable washing machine appliance, such as a horizontal axis washing machine appliance. Indeed, modifications and variations may be made to washing machine appliance, including different configurations, different appearances, and/or different features while remaining within the scope of the present subject matter.

102 100 118 118 116 114 114 100 120 118 116 120 120 114 114 122 120 114 120 100 120 124 120 120 118 120 102 2 FIG. 1 3 FIGS.and 2 FIG. As illustrated, cabinetof washing machine appliancehas a top panel. Top paneldefines an opening () that coincides with openingof wash basketto permit a user access to wash basket. Washing machine appliancefurther includes a doorwhich is rotatably mounted to top panelto permit selective access to opening. In particular, doorselectively rotates between the closed position (as shown in) and the open position (as shown in). In the closed position, doorinhibits access to wash basket. Conversely, in the open position, a user can access wash basket. A windowin doorpermits viewing of wash basketwhen dooris in the closed position, e.g., during operation of washing machine appliance. Dooralso includes a handlethat, e.g., a user may pull and/or lift when opening and closing door. Further, although dooris illustrated as mounted to top panel, doormay alternatively be mounted to cabinetor any other suitable support.

2 3 FIGS.and 3 FIG. 114 126 114 108 114 108 110 110 126 128 108 100 130 108 114 108 As best shown in, wash basketfurther defines a plurality of perforationsto facilitate fluid communication between an interior of wash basketand wash tub. In this regard, wash basketis spaced apart from wash tubto define a space for wash fluid to escape wash chamber. During a spin cycle, wash fluid within articles of clothing and within wash chamberis urged through perforationswherein it may collect in a sumpdefined by wash tub. Washing machine appliancefurther includes a pump assembly() that is located beneath wash tuband wash basketfor gravity assisted flow when draining wash tub.

132 114 114 132 114 114 100 132 132 114 3 FIG. 3 FIG. An impeller or agitation element(), such as a vane agitator, impeller, auger, oscillatory basket mechanism, or some combination thereof is disposed in wash basketto impart an oscillatory motion to articles and liquid in wash basket. More specifically, agitation elementextends into wash basketand assists agitation of articles disposed within wash basketduring operation of washing machine appliance, e.g., to facilitate improved cleaning. In different embodiments, agitation elementincludes a single action element (i.e., oscillatory only), a double action element (oscillatory movement at one end, single direction rotation at the other end) or a triple action element (oscillatory movement plus single direction rotation at one end, single direction rotation at the other end). As illustrated in, agitation elementand wash basketare oriented to rotate about axis of rotation A (which is substantially parallel to vertical direction V).

3 FIG. 100 138 114 114 100 138 132 138 114 132 100 As best illustrated in, washing machine applianceincludes a drive assembly or motor assemblyin mechanical communication with wash basketto selectively rotate wash basket(e.g., during an agitation or a rinse cycle of washing machine appliance). In addition, motor assemblymay also be in mechanical communication with agitation element. In this manner, motor assemblymay be configured for selectively rotating or oscillating wash basketand/or agitation elementduring various operating cycles of washing machine appliance.

138 140 142 114 132 140 140 140 138 More specifically, motor assemblymay generally include one or more of a drive motorand a transmission assembly, e.g., such as a clutch assembly, for engaging and disengaging wash basketand/or agitation element. According to the illustrated embodiment, drive motoris a brushless DC electric motor, e.g., a pancake motor. However, according to alternative embodiments, drive motormay be any other suitable type or configuration of motor. For example, drive motormay be an AC motor, an induction motor, a permanent magnet synchronous motor, or any other suitable type of motor. In addition, motor assemblymay include any other suitable number, types, and configurations of support bearings or drive mechanisms.

1 3 FIGS.through 100 180 1 200 114 180 102 120 100 1 180 100 180 1 2 180 1 186 Referring to, washing machine appliancemay include one or more imaging devices(e.g., cameras, LiDAR, radar, etc.) for detecting a travel distance Dof the articleswithin the wash basket. The cameramay be mounted to the cabinet, the door, or any other appropriate position at the washing machine appliancefor detecting the travel distance D. The cameramay be configured to determine one or more discrete or transient movements of rotary components of the washing machine appliance. Certain embodiments may configure the cameraconfigured to determine whether the travel distance Dhas met or exceeded a set distance D, such as described with regard to one or methods herein. The cameramay include various components for detecting the travel distance D, such as a light.

1 3 FIGS.through 1 FIG. 150 152 118 150 152 154 150 Referring still to, a control panelwith at least one input selector() extends from top panel. Control paneland input selectorcollectively form a user interface input for operator selection of machine cycles and features. A displayof control panelindicates selected features, operation mode, a countdown timer, and/or other items of interest to appliance users regarding operation.

100 156 150 150 156 100 150 156 180 170 156 156 150 100 156 Operation of washing machine applianceis controlled by a controller or processing devicethat is operatively coupled to control panelfor user manipulation to select washing machine cycles and features. In response to user manipulation of control panel, controlleroperates the various components of washing machine applianceto execute selected machine cycles and features. The control paneland/or controlleris configured in operative communication with the cameraand other sensors (e.g., sensor), such as to receive and communicate via output signals, fault signals, validation signals, power output or consumption signals, current signal, voltage signal, or other energy parameter signal, speed signals, or thresholds, such as further described herein. According to an example embodiment, controllermay include a memory and microprocessor, such as a general or special purpose microprocessor operable to execute programming instructions or micro-control code associated with methods described herein. Alternatively, controllermay be constructed without using a microprocessor, e.g., using a combination of discrete analog and/or digital logic circuitry (such as switches, amplifiers, integrators, comparators, flip-flops, AND gates, and the like) to perform control functionality instead of relying upon software. Control paneland other components of washing machine appliancemay be in communication with controllervia one or more signal lines or shared communication busses.

1 FIG. 190 190 100 100 190 Referring still to, a schematic diagram of an external communication systemwill be described according to an example embodiment of the present subject matter. In general, external communication systemis configured for permitting interaction, data transfer, and other communications between washing machine applianceand one or more external devices. For example, this communication may be used to provide and receive operating parameters, user instructions or notifications, performance characteristics, user preferences, or any other suitable information for improved performance of washing machine appliance. In addition, it should be appreciated that external communication systemmay be used to transfer data or other information to improve performance of one or more external devices or appliances and/or improve user interaction with such devices.

190 156 100 100 192 194 192 100 192 For example, external communication systempermits controllerof washing machine applianceto communicate with a separate device external to washing machine appliance, referred to generally herein as an external device. As described in more detail below, these communications may be facilitated using a wired or wireless connection, such as via a network. In general, external devicemay be any suitable device separate from washing machine appliancethat is configured to provide and/or receive communications, information, data, or commands from a user. In this regard, external devicemay be, for example, a personal phone, a smartphone, a tablet, a laptop or personal computer, a wearable device, a smart home system, or another mobile or remote device.

196 100 192 194 196 196 192 196 194 100 192 196 100 In addition, a remote servermay be in communication with washing machine applianceand/or external devicethrough network. In this regard, for example, remote servermay be a cloud-based server, and is thus located at a distant location, such as in a separate state, country, etc. According to an example embodiment, external devicemay communicate with a remote serverover network, such as the Internet, to transmit/receive data or information, provide user inputs, receive user notifications or instructions, interact with or control washing machine appliance, etc. In addition, external deviceand remote servermay communicate with washing machine applianceto communicate similar information.

100 192 196 192 100 194 194 In general, communication between washing machine appliance, external device, remote server, and/or other user devices or appliances may be carried using any type of wired or wireless connection and using any suitable type of communication network, non-limiting examples of which are provided below. For example, external devicemay be in direct or indirect communication with washing machine appliancethrough any suitable wired or wireless communication connections or interfaces, such as network. For example, networkmay include one or more of a local area network (LAN), a wide area network (WAN), a personal area network (PAN), the Internet, a cellular network, any other suitable short-or long-range wireless networks, etc. In addition, communications may be transmitted using any suitable communications devices or protocols, such as via Wi-Fi®, Bluetooth®, Zigbee®, wireless radio, laser, infrared, Ethernet type devices and interfaces, etc. In addition, such communication may use a variety of communication protocols (e.g., TCP/IP, HTTP, SMTP, FTP), encodings or formats (e.g., HTML, XML), and/or protection schemes (e.g., VPN, secure HTTP, SSL).

190 190 External communication systemis described herein according to an example embodiment of the present subject matter. However, it should be appreciated that the example functions and configurations of external communication systemprovided herein are used only as examples to facilitate description of aspects of the present subject matter. System configurations may vary, other communication devices may be used to communicate directly or indirectly with one or more associated appliances, other communication protocols and steps may be implemented, etc. These variations and modifications are contemplated as within the scope of the present subject matter.

100 114 116 152 114 112 100 108 114 114 114 132 114 During operation of washing machine appliance, laundry items are loaded into wash basketthrough opening, and washing operation is initiated through operator manipulation of input selectors. Wash basketis filled with water and detergent and/or other fluid additives via primary dispenser. One or more valves can be controlled by washing machine applianceto provide for filling wash tuband wash basketto the appropriate level for the amount of articles being washed and/or rinsed. By way of example for a wash mode, once wash basketis properly filled with fluid, the contents of wash basketcan be agitated (e.g., with agitation elementas discussed previously) for washing of laundry items in wash basket.

3 FIG. 100 160 162 164 110 100 166 160 156 156 166 108 More specifically, referring again to, a water fill process will be described according to an example embodiment. As illustrated, washing machine applianceincludes a water supply conduitthat provides fluid communication between a water supply source(such as a municipal water supply) and a discharge nozzlefor directing a flow of water into wash chamber. In addition, washing machine applianceincludes a water fill valve or water control valvewhich is operably coupled to water supply conduitand communicatively coupled to controller. In this manner, controllermay regulate the operation of water control valveto regulate the amount of water within wash tub.

160 162 164 166 110 160 162 100 170 108 170 108 108 156 110 170 170 Although water supply conduit, water supply source, discharge nozzle, and water control valveare all described and illustrated herein in the singular form, it should be appreciated that these terms may be used herein generally to describe a supply plumbing for providing hot and/or cold water into wash chamber. In this regard, water supply conduitmay include separate conduits for receiving hot and cold water, respectively. Similarly, water supply sourcemay include both hot-and cold-water supplies regulated by dedicated valves. In addition, washing machine appliancemay include one or more fluid level sensorsfor detecting the amount of water and or clothes within wash tub. For example, fluid level sensormay be operably coupled to a side of tubfor detecting the weight, load, or pressure of wash tub, which controllermay use to determine a volume of water in wash chamberand a sub-washer load weight. The fluid level sensormay form a sensor configured to determine one or more discrete values of pressure, load, weight, or moisture. Certain embodiments of the fluid level sensormay form a switch configured to determine whether a threshold value has been met or exceeded.

108 114 130 114 132 114 114 126 130 108 114 114 114 116 After wash tubis filled and the agitation phase of the wash cycle is completed, wash basketcan be drained, e.g., by drain pump assembly. Laundry articles can then be rinsed by again adding fluid to wash basketdepending on the specifics of the cleaning cycle selected by a user. The impeller or agitation elementmay again provide agitation within wash basket. One or more spin cycles may also be used as part of the cleaning process. In particular, a spin cycle may be applied after the wash cycle and/or after the rinse cycle in order to wring wash fluid from the articles being washed. During a spin cycle, wash basketis rotated at relatively high speeds to help wring fluid from the laundry articles through perforations. During or prior to the spin cycle, drain pump assemblymay operate to discharge wash fluid from wash tub, e.g., to an external drain. After articles disposed in wash basketare cleaned and/or washed, the user can remove the articles from wash basket, e.g., by reaching into wash basketthrough opening.

2 3 FIGS.and 100 180 110 100 180 120 100 120 180 110 110 180 108 180 110 114 Referring now specifically to, washing machine appliancemay further include the imaging devicethat is generally positioned and configured for obtaining images within wash chamberof washing machine appliance. Specifically, according to the illustrated embodiment, the camera assemblymay be mounted to an underside of doorof washing machine appliance. In this manner, when dooris in the closed position, cameramay be positioned over wash chamberand may be oriented for obtaining images within wash chamber. Specifically, camerais mounted such that is faces toward a bottom side of wash tub. In this manner, cameracan take unobstructed images or video of an inside of wash chamber, e.g., including images of wash basket.

180 110 180 180 110 180 164 100 It should be appreciated that cameramay include any suitable number, type, size, and configuration of camera(s) for obtaining images of wash chamber. In general, camerasmay include a lens that is constructed from a clear hydrophobic material or which may otherwise be positioned behind a hydrophobic clear lens. So positioned, cameramay obtain one or more images or videos within wash chamber, as described in more detail below. It should be appreciated that other locations for mounting the cameraare possible, such as below or adjacent a discharge nozzleof washing machine appliance.

2 3 FIGS.through 2 FIG. 100 186 102 110 110 186 180 186 102 100 102 Referring still to, washing machine appliancemay further include the tub lightthat is positioned within cabinetor wash chamberfor selectively illuminating wash chamberand the load of articles, or clothes, positioned therein. Specifically, as shown in, tub lightmay be integrated with the cameraand may be positioned thereupon. According to still other embodiments, tub lightmay be positioned at any other suitable location within cabinet. It should be appreciated that according to alternative embodiments, washing machine appliancemay include any other camera or system of imaging devices for obtaining images of the load of clothes. In addition, these cameras may be positioned at any suitable location within cabinet, may include any suitable lighting features, and may utilize any suitable photography or imaging technology.

156 100 180 186 100 156 180 100 Notably, controllerof washing machine appliance(or any other suitable dedicated controller) may be communicatively coupled to camera, tub light, and other components of washing machine appliance. As explained in more detail below, controllermay be programmed or configured for analyzing the images obtained by camera, e.g., in order to assess agitation effectiveness, and may use this information to make informed decisions regarding the operation of washing machine appliance.

100 156 300 300 300 100 300 156 300 156 300 138 180 130 156 300 Now that the construction of washing machine applianceand the configuration of controlleraccording to example embodiments have been presented, an example methodof operating a washing machine appliance will be described (hereinafter, “method”). Although the discussion below refers to the example methodof operating washing machine appliance, one skilled in the art will appreciate that the example methodis applicable to the operation of a variety of other washing machine appliances, such as horizontal axis washing machine appliances. In the example embodiments, the various method steps as disclosed herein may be performed by controlleror a separate, dedicated controller. Steps of the methodmay be stored as instructions in one or more memory devices associated with the controller. Steps of the methodmay be executed by embodiments of the motor assembly, camera, and drain pump assemblysuch as provided herein. Accordingly, the controlleror other control device may be configured to perform operations such as provided in one or more steps of the method.

5 FIG. 300 300 302 302 152 156 152 Referring now to, a flowchart outlining example steps of the methodof operating a washing machine appliance is provided. The methodincludes atreceiving a wash cycle operation signal. Stepmay include a user manually selecting at the input selectors, which wash cycle operation should be completed. The controllermay receive the wash cycle operation signal from the input selectors.

304 300 110 180 304 138 114 3 304 At, the methodincludes initiating the wash cycle operation including capturing a plurality of images of the wash chamber (e.g., wash chamber) with the camera. Stepmay also include instructing the motor assemblyto rotate the wash basket (e.g., wash basket) to at least a rotated distance D. In this regard, for example, initiation of the wash cycle operation generally involves the identification of a variety of wash parameters based on the type of wash cycle desired. For example, the load size for a given wash may be associated with a predetermined targeted water level within the wash tub. In another example, the agitation profile, which may depend upon the wash cycle type (e.g., delicates, heavy-duty, etc.), may be associated with a predetermined intensity of movement targeted by the agitation element or impeller, such as, for example, the agitator ramp up speed or the length of time the agitator is activated. In still other examples, the temperature setting of the washing machine appliance may be associated with a given water temperature to be used with each particular setting. Accordingly, at step, a wash cycle operation may be initiated employing the predetermined parameters associated with the various settings for the particular cycle.

166 108 114 138 114 114 132 114 114 200 114 114 132 156 138 114 132 156 100 114 114 132 Continuing the example from above, at the beginning of the wash cycle operation, water control valvemay be regulated to supply wash fluid into wash tubafter the load of articles has been added to wash basket. Motor assemblymay be activated when the wash fluid reaches the desired fill level in order to agitate and clean the load of clothes within wash basket. More specifically, agitation may be achieved by selectively rotating wash basketand/or agitation element, thereby generating rotation of the load of clothes within wash basket. As explained above, rotation is generally a measure of the movement of articles of clothing within wash basketduring a period of time. The period of time starts at an initial change of direction (e.g., clockwise) and resets (i.e., ends and starts again) at a subsequent change of direction (e.g., counterclockwise) of the articleswithin the wash basket. Additionally, or alternatively, the period of time may start and reset based on respective initial change of direction and a subsequent change of direction of the wash basketand/or agitation element. For example, the direction the controllerinstructs the motor assemblyto rotate the wash basketand/or the agitation elementmay be stored in memory of the controller. According to an exemplary embodiment, washing machine appliances that include central agitation element, e.g., such as washing machine appliance, facilitate a rotational process where the clothes at the top of wash basketgenerally move arcuately around the center of the wash basketand/or agitation element.

304 180 1 114 Stepalso generally includes obtaining a series of image frames using a camera. In this regard, for example, cameramay obtain one or more images, a series of frames, a video, or any other suitable visual representation of the load of articles. As will be explained in more detail below, this series of image frames may be used to monitor the motion or rotation (e.g., travel distance D) of the load of articles within wash basket.

114 400 402 110 180 114 400 114 180 404 400 114 180 404 400 According to the illustrated embodiment, wash basketincludes bottom walland a cylindrical outer wallwhich collectively define at least a portion of wash chamber. As illustrated, camerais generally mounted above wash basketand has a field of view directed toward bottom wallof wash basket. For example, according to the illustrated embodiment, camera assemblyis positioned directly over a centera bottom wallof wash basket. According to such an embodiment, the field of view of camera assemblymay be directed directly down along the vertical direction V toward centerof bottom wall.

306 1 306 410 200 114 416 4 5 FIGS.and Stepincludes calculating the travel distance Dof the articles. Stepmay generally include identifying a tracking point on one article from the load of articles using a first image frame from the series of image frames. In this regard, as a starting point for monitoring the rotation of the load of articles within a wash basket, the first image frame of the series of image frames may be used to identify a specific location or feature on a specific garment within the load of clothes for tracking purposes. For example, referring briefly to, a first image frameof the series of images is provided and shows a load of articlesillustrated within a wash basketaccording to an example embodiment of the present subject matter. A tracking pointmay be identified using any suitable image processing technique or analysis, examples of which may be described below.

4 6 FIGS.through 5 FIG. 5 FIG. 306 1 416 200 410 420 416 1 1 114 114 1 114 1 Referring again to, stepmay generally include generating the travel distance Dof the tracking point over the series of image frames using an optical flow technique. In this regard, by analyzing the series of image frames, the tracking pointon load of articlesmay be identified in each frame (e.g., a first image frameand a subsequent image frame), and the path of travel of that specific point may be determined. A schematic representation of the motion path of tracking pointthrough a series of image frames is provided within a horizontal plane inand identified generally by D. In this regard, travel distance Dgenerally begins at one location of wash basketand moves arcuately along the center of the basket. It should be appreciated that travel distance Dillustrated inis overlaid on wash basketonly for purposes of describing aspects of the present subject matter. The travel distance Dis only exemplary and may vary while remaining within the scope of the present subject matter.

180 156 196 As used herein, the terms “optical flow” and the like are generally intended to refer to any suitable process for analyzing a series of image frames or processing a video for tracking a target object or point. These algorithms or techniques may be used to track the motion of object, surfaces, edges, corners, etc. in a two-dimensional or three-dimensional space. This technique may be applied to a series of images or video frames that have a small time step between them and may include calculating a velocity for points within the images as well as an estimation of where points could be in the next frame. For example, an optical flow algorithm may generally analyze or track the pixels of consecutive frames of a video file to track a specific point or object within the video. This optical flow algorithm may be implemented using cameraand controlleror may be implemented using a remote analysis device (e.g., located on remote server).

Various optical flow algorithms may be utilized according to exemplary embodiments of the present subject matter. In this regard, for example, suitable flow algorithms may include dense optical flow (e.g., which may estimate flow vectors for all pixels within a frame), sparse optical flow (e.g., which may estimate flow vectors for pixels containing objects of interest, edges, corners, etc.), or variations therebetween. According to still other embodiments, optical flow techniques may include phase correlation, block-based methods, discrete optimization methods, or differential methods of estimating optical flow (e.g., based on partial derivatives of the image signal and/or the sought flow field and higher-order partial derivatives). For example, differential methods may include a Lucas-Kanade method, a Horn-Schunck method, a Buxton-Buxton method, a Black-Jepson method, and/or general variational methods (e.g., modifications or extension of the methods described herein).

In addition, or alternatively, various techniques for identifying tracking points within a region of interest may be used, such as Shi-Tomasi corner detection, Harris corner detection, Farneback optical flow, Lucas-Kanade techniques, or any other suitable techniques may be used. It should be appreciated that other known techniques of optical flow analysis are possible and within the scope of the present subject matter. Corner detection methods may be used to identify corners or edges for use as tracking points. In general, corner detections may include, but are not limited to Moravec corner detection algorithms, Harris and Stephens corner detection algorithms, Shi-Tomasi corner detection algorithms, Förstner corner detection algorithms, multi-scale Harris operators, level curve curvature approaches, Laplacian of Gaussian methods, Wang and Brady corner detection algorithms, SUSAN (smallest uni-value segment assimilating nucleus) methods, Trajkovic and Hedley corner detector, AST-based (accelerated segment test) feature detectors, or any other suitable corner detection method known to one having ordinary skill in the art, or combinations therebetween.

One exemplary implementation of the optical flow technique includes the use of a frame-by-frame analysis of a specific pixel window that includes the target tracking point. In this regard, for example, a target tracking point may be identified in the first frame along with a pixel window surrounding the tracking point (e.g., with the tracking point as its center). The size of the pixel window may vary depending on the projected movement of the tracking point, but for purposes of explanation the size of the pixel window may be a 20×20 pixel window (i.e., 400 total pixels). For the second frame, the optical flow process may analyze the original pixel window from the first frame to again identify the tracking point, which has now moved from the center of the pixel window. A new pixel window with the new tracking point may be identified and the process may proceed through the series of image frames to track the coordinates or location of the tracking point over time.

414 1 1 300 410 414 1 300 200 300 As described above, a single tracking pointis used to generate a single travel distance Dfor assessing agitation effectiveness. However, it should be appreciated that according to alternative embodiments, multiple travel distances Dmay be used to obtain a more accurate assessment of the agitation effectiveness. For example, methodmay include identifying a plurality of tracking points at the start of the period of time from the load of articles from within the first image frameand may simultaneously track these tracking pointsto generate multiple travel distances Dfor each tracking point over the series of images. The methodmay include selecting new tracking points when the period of time resets. The data associated with each of these travel distances may be averaged for an improved estimation of the agitation effectiveness of the load of articles. For example, according to example embodiments, methodmay include simultaneously tracking between about 10 and about 200 tracking points, between about 20 and about 100 tracking points, or about 50 tracking points.

414 114 In addition, although the process of resetting tracking pointis described herein with reference to wash basket, it should be appreciated the process may vary for a wash basket that includes an agitator that generally facilitates cloth movement from the outside toward a center of the wash basket. Specifically, according to such an embodiment, the tracking point may be reset when falls inside a predetermined radial distance defined around the center of the wash basket. It should be appreciated that other methods of resetting one or more tracking points are possible and within the scope of the present subject matter.

308 308 156 3 114 132 114 132 3 200 1 3 200 1 3 156 3 1 The method may include a step. At, the controllercalculates a rotation distance Dof the wash basketand/or the agitation element. For example, as the wash basketand/or the agitation elementrotates a rotation distance D, forces act on the articles(e.g., frictional forces) to lessen a magnitude of the travel distance Dcompared to the rotation distance D. The small the load, the fewer forces act on the articlesto decrease the travel distance Drelative to the rotation distance D. The controllermay calculate the rotation distance Dusing a look-up table stored in memory or a suitable equation stored in memory based on the measured travel distance D, load size, water volume, etc.

310 300 1 2 2 2 At, the methodincludes comparing the travel distance Dto a set distance D. In this regard, the set distance Dmay correspond to a minimum desired magnitude of the travel distance Dof the load of clothes for facilitating suitable agitation and cleaning action for a given operating cycle and parameters.

2 3 2 1 414 200 404 2 1 2 2 414 200 402 114 2 2 114 200 114 404 2 114 404 402 2 114 402 2 404 The set distance Dmay be programmed by the manufacturer, set by the user, and may be dependent on a variety of operating parameters or conditions. For example, according to an exemplary embodiment, the set distance may be based on at least one of a load size, a load type, a cycle selection, rotation distance D, etc. The set distance Dmay also depend on a first space Sbetween the tracking pointof the articleand the center. The set distance Dmay increase as the first space Sincreases due to, for example, rotation about a fixed axis increasing total distance as rotation occurs further from the fixed axis within a period of time. Additionally, or alternatively, the set distance Dmay depend on a second space Sbetween the tracking pointof the articleand that outer wallof the wash basket. The set distance Dmay increase as the second space Sincreases due to, for example, less frictional interact between the wash basketand the article. For example, a first area of the wash basketproximal the centermay have a set distance Dof about 50 pixels to 150 pixels, about 75 pixels to 125 pixels, or about 100 pixels; a second area of wash basketbetween the centerand the outer wallmay have a set distance Dof about 100 pixels to about 350 pixels, 150 pixels to about 250 pixels, or about 200 pixels; and a third area of the wash basketproximal the outer wallmay have a set distance Dof about 50 pixels to 150 pixels, about 75 pixels to 125 pixels, or about 100 pixels. The first region, the second region, and the third region may be spaced from the centerin about equal increments of a third (e.g., about equal bands where band width is outer diameter less the respective inner diameter).

312 1 2 1 2 156 314 1 2 316 318 At, the controller determines whether the travel distance Dis at least as great as the set distance D. In response to the travel distance Dbeing equal to or greater than the set distance D, the controllerwill complete the wash cycle operation (step). In response to the travel distance Dbeing less than the set distance D, the method will proceed to stepsand.

316 318 300 100 154 1 2 190 192 1 2 308 114 132 156 138 114 132 Atand, the methodgenerally includes generating an output signal. The output signal is based on the articles within the wash basket failing to rotate at least the set distance within the period of time. The output signal may be configured to alert a user. The alert may include indicating, at the washing machine appliance(e.g., via the display, that the travel distance Dis less than the set distance D. The alert may also include communicating via the external communication system, e.g., a user notification to the remote deviceof the user, that the travel distance Dis less than the set distance D. The alert may include a generic message, such as “Ineffective Wash Cycle Operation,” for example only. The alert may also be based on step. For example, the alert may indicate that the wash basketand/or the agitation elementhave rotated less than expected. The alert may, for example, indicate that there is a malfunction with one of the controller, motor assembly, the wash basket, and/or the agitation element, etc.

100 130 170 300 The washing machine appliancemay include a drain pumpand implementing the responsive action may include operating the drain pump to decrease a water level within the wash tub. Decreasing the water level within the wash tub may include emptying the wash tub of water. The water level may be determined by the sensor(e.g., a fluid level sensor, a pressure sensor, moisture sensor, a load sensor, or other appropriate device for determining the presence of fluid in a wash tub). Thus, methodmay include automatically stopping, or abating, a wash cycle operation or otherwise adjusting the duration of the wash cycle based on the generated output signal that is based on the articles within the wash basket failing to rotate at least the set distance within the period of time.

As explained above, aspects of the present subject matter are directed to a method of assessing agitation effectiveness within a washing machine using a camera fixed in the unit and pointing towards a load during agitation. Article movements may be tracked by placing a set of points in the center for impeller models since the starting point of cloth movement in impeller models is in the center. The starting point placement may be set using a corner detection method like Shi Tomasi corner detection or Harris corner detection to locate good features to track in the specified starting region of interest (ROI). The ROI can be different based on the washer model (impellor vs. agitator models). After starting points are placed, Lucas-Kanade method may be used to calculate optical flow while agitation is in progress. The travel distance of the articles may be estimated by calculating distance from the starting points to the new points generated using optical flow during agitation. The points may reset to a new starting location based on a period of time (e.g., directional change). Based on the travel distance, the agitation profile and the water level may be adjusted to maximize agitation which in turn will improve washing performance.

This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they include structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal languages of the claims.