Patent Description:
Besides just aesthetic appearance, cleaning the surfaces of manufactured parts is an essential, and in many applications required, process to prepare the part for further processing, such as applying a new finish or assembling the part into a larger component. Conventional methods for removing contaminants, debris or other contamination from objects or surfaces may depend on many factors, such as the nature of the contamination, the requirements for the cleanliness, the shape and size of the object or surface and the like. Generally, conventional cleaning methods fall into two main categories, namely, chemical cleaning and mechanical cleaning.

Conventional cleaning methods have various limitations, such as inconsistent cleaning quality and certain surfaces (e.g., complex surfaces or interior surfaces) may be difficult to reach or access.

Accordingly, those skilled in the art continue with research and development efforts in the field of surface cleaning of objects.

<CIT> describes, according to its abstract, a robotically operated device using an ultrasonic transducer for the cleaning of ships' hulls. The device may also be used for spraying paints or other chemicals on the sides of ships' hulls. The device includes a housing having an open face adapted to confront a ship's hull and apparatus disposed in the housing for impinging a flow of fluid through the open face onto the ship's hull. An ultrasonic transducer is disposed in the housing for impinging a flow of ultrasonic energy through the open face onto the ship's hull. Apparatus connected to the outside of the housing retains the housing on the ship's hull and moves the housing on the ship's hull. In an additional embodiment, apparatus for spraying paint or other chemicals on a ship's hull is disposed in the housing.

German patent document <CIT> describes, according to its abstract, a system for cleaning sheet- or plate-like objects, in particular for cleaning electrodes and/or separators for constructing an electrochemical energy storage means or cleaning parts of such electrodes or separators, wherein the sheet- or plate-like objects have a first object side and a second object side, which is situated opposite the first object side, and at least one side surface which connects the first object side and the second object side. The cleaning system has: a first conveyor belt for moving the object to a first cleaning apparatus, wherein the first conveyor belt is arranged and designed in such a way that it holds the object such that the second object side faces the first conveyor belt; the first cleaning apparatus which is arranged and designed in such a way that it can clean the first object side and at least one side surface of the object on the first conveyor belt; a second conveyor belt for taking the object from the first conveyor belt and moving the object to a second cleaning apparatus, wherein the second conveyor belt is arranged and configured in such a way that it holds the object such that the first object side faces the second conveyor belt; and the second cleaning apparatus which is arranged and designed in such a way that it can clean the second object side and at least one side surface of the object on the second conveyor belt.

<CIT> describes, according to its abstract, a method for cleaning a substrate that includes applying a liquid medium to a surface of the substrate such that the liquid medium substantially covers a portion of the substrate that is being cleaned. One or more transducers are used to generate acoustic energy. The generated acoustic energy is applied to the substrate and the liquid medium meniscus such that the applied acoustic energy to the liquid medium prevents cavitation within the liquid medium. The acoustic energy applied to the substrate provides maximum acoustic wave displacement to acoustic waves introduced into the liquid medium. The acoustic energy introduced into the substrate and the liquid medium enables dislodging of the particle contaminant from the surface of the substrate. The dislodged particle contaminants become entrapped within the liquid medium and are carried away from the surface of the substrate by the liquid medium.

<CIT> describes, according to its abstract, a system for cleaning a workpiece or wafer, in which a boundary layer of heated liquid is formed on the workpiece surface. Ozone is provided around the workpiece. The ozone diffuses through the boundary layer and chemically reacts with contaminants on the workpiece surface. A jet of high velocity heated liquid is directed against the workpiece, to physically dislodge or remove a contaminant from the workpiece. The jet penetrates through the boundary layer at the point of impact. The boundary layer otherwise remains largely undisturbed. Preferably, the liquid includes water, and may also include a chemical. Steam may also be jetted onto the workpiece, with the steam also physically removing contaminants, and also heating the workpiece to speed up chemical cleaning. The workpiece and the jet of liquid are moved relative to each other, so that substantially all areas of the workpiece surface facing the jet are exposed at least momentarily to the jet. Sonic or electromagnetic energy may also be introduced to the workpiece.

According to an aspect of the present invention to which this European patent is directed there is provided a system of claim <NUM> for cleaning
an object comprising a surface, said system comprising: a steam source comprising a water tank and a heating mechanism to generate steam; a cleaning head including a vacuum chamber having an open end; a cleaning medium dispenser comprising a nozzle configured to deliver the steam to said surface, wherein said steam dislodges and captures debris from said surface; a plurality of ultrasonic devices configured to deliver ultrasonic waves to said object, wherein said ultrasonic waves atomize said steam and captured debris from said surface; wherein at least one of the plurality of ultrasonic devices is located within the vacuum chamber, and at least one of the ultrasonic devices is located outside of the vacuum chamber; and a vacuum configured to provide a vacuum airflow within the vacuum chamber, wherein said vacuum airflow collects atomized steam and captured debris.

Optionally said ultrasonic waves generate ultrasonic vibrations on said surface of said object.

Optionally said ultrasonic waves generate ultrasonic vibrations in said object.

Optionally said ultrasonic waves comprise at least one of longitudinal waves, shear waves, surface waves and plate waves.

Optionally a position of said cleaning medium dispenser, said plurality of ultrasonic devices and said vacuum are adjustable with respect to said surface.

Optionally said cleaning medium dispenser, said plurality of ultrasonic devices and said vacuum are mounted to the cleaning head.

Optionally said cleaning head is mounted to a movable assembly, wherein said movable assembly positions said cleaning head relative to said surface.

Optionally said ultrasonic waves are focused to a cleaning zone on said surface.

Optionally the system further comprises a holding fixture configured to hold said object, wherein said holding fixture defines an acoustically resonating system, and wherein said ultrasonic waves generate ultrasonic vibrations in said object.

Preferably said plurality of ultrasonic devices is coupled to said holding fixture; and said cleaning medium dispenser and said vacuum are mounted to a cleaning head.

Optionally said plurality of ultrasonic devices is coupled to said holding fixture; and a position of said cleaning medium dispenser and said vacuum are adjustable with respect to said object.

Optionally said plurality of ultrasonic devices is physically coupled to said holding fixture.

Preferably said plurality of ultrasonic devices is air coupled to at least one of said holding fixture and said object.

Optionally said cleaning medium dispenser, said plurality of ultrasonic devices and said vacuum are mounted to the cleaning head; said holding fixture comprises a second ultrasonic device configured to deliver second ultrasonic waves through said holding fixture and into said object; and said ultrasonic waves and said second ultrasonic waves generate said ultrasonic vibrations in said object to atomize said steam from said surface.

Preferably said holding fixture is a part of said object.

Optionally the system further comprises a second ultrasonic device configured to deliver second ultrasonic waves to said object.

Optionally said ultrasonic device is air coupled to said object;.

Optionally the system further comprises a holding fixture configured to hold said object, wherein said holding fixture defines an acoustically resonating system, and wherein said ultrasonic waves and said second ultrasonic waves generate said ultrasonic vibrations in said object to atomize said steam from said surface.

Preferably said second ultrasonic device is physically coupled to said holding fixture.

Preferably said ultrasonic device is air coupled to at least one of said object and said holding fixture.

Optionally the system further comprises a plurality of ultrasonic devices arranged in an acoustic array, wherein said plurality of ultrasonic devices deliver said ultrasonic waves to said object.

Preferably said ultrasonic waves generate a pattern of ultrasonic vibrations in said obj ect.

Preferably said acoustic array comprises at least one of a parametric array and a phased array.

Preferably said plurality of ultrasonic devices is air coupled to said object.

Optionally the system further comprises a holding fixture configured to hold said object, and wherein said holding fixture defines an acoustically resonating system.

Optionally at least a portion of said plurality of ultrasonic devices is physically coupled to said holding fixture.

Preferably at least a portion of said plurality of ultrasonic devices is air coupled to at least one of said holding fixture and said object.

Optionally said steam disintegrates and dislodges said debris from said surface.

Optionally said ultrasonic waves reduce adhesion between said surface and said debris.

According to another aspect of the present invention to which this European patent is directed there is provided a method of claim <NUM>
for cleaning an object comprising a surface, said method comprises: generating steam using a water tank and a heating mechanism; delivering the steam to said surface; delivering ultrasonic waves emitted by a plurality of ultrasonic devices to said object to atomize said steam; and applying a vacuum airflow to collect atomized steam; wherein at least one of the plurality of ultrasonic devices is located within a vacuum chamber, and at least one of the plurality of ultrasonic devices is located outside of the vacuum chamber.

Optionally the method further comprises: mounting said object to a holding fixture, wherein said holding fixture defines an acoustically resonating system; and delivering said ultrasonic waves to at least one of said holding fixture and said object to generate ultrasonic vibrations in said object.

Optionally the method further comprises: focusing said ultrasonic waves on a cleaning zone on said surface; and generating a pattern of ultrasonic vibrations in said obj ect.

Preferably said step of generating said pattern of ultrasonic vibrations comprises defining an ultrasonic interaction volume around at least a portion of said surface through interference of said ultrasonic waves.

Optionally said steam dislodges a debris from said surface.

Other aspects of the disclosed system and method will become apparent from the following detailed description, the accompanying drawings and the appended claims.

The following detailed description refers to the accompanying drawings, which illustrate specific aspects of the disclosure. Other aspects having different structures and operations do not depart from the scope of the present disclosure. Like reference numerals may refer to the same element or component in the different drawings.

Referring to Fig.l, one aspect of the disclosed system, generally designated <NUM>, for surface cleaning of an object may include a cleaning assembly <NUM> utilized for cleaning one or more surfaces <NUM> of one or more objects <NUM>, such as during fabrication, assembly and/or maintenance of the object <NUM>. For example, the object <NUM> may include any manufactured part, component, assembly or sub-assembly having a large and/or complex surface <NUM>, including, but not limited to, complex three-dimensional objects <NUM> and/or large two-dimensional objects <NUM>, such as an aircraft component (e.g., an airplane wing).

The cleaning assembly <NUM> includes at least one ultrasonic device <NUM>, at least one cleaning medium dispenser <NUM> and at least one vacuum <NUM>. The cleaning medium dispenser <NUM> delivers a cleaning medium <NUM> to the surface <NUM> of the object <NUM>. The ultrasonic device <NUM> delivers ultrasonic waves <NUM> to the object <NUM> to generate ultrasonic vibrations within (e.g., throughout at least a portion of) the object <NUM> and/or on the surface <NUM> of the object to atomize the cleaning medium <NUM>. The vacuum <NUM> removes the atomized cleaning medium <NUM> along with any debris <NUM> collected by the cleaning medium <NUM> from the surface <NUM> of the object <NUM>.

As used herein, debris <NUM> may include any contaminant, substance and/or other unwanted constituent material disposed on the surface <NUM> of the object <NUM>. Debris <NUM> may include any solid, semi-solid, liquid and/or semi-liquid material of any type, without limitation.

The ultrasonic device <NUM>, the cleaning medium dispenser <NUM> and the vacuum <NUM> may be mounted to a cleaning head <NUM>. The cleaning head <NUM> may deliver cleaning medium <NUM> (e.g., from the cleaning medium dispenser <NUM>), ultrasonic waves <NUM> (e.g., from the ultrasonic device <NUM>) and vacuum airflow <NUM> (e.g., from the vacuum <NUM>) directly to a cleaning zone <NUM> on the surface <NUM> of the object <NUM>.

An ultrasonic generator <NUM> may be coupled to the cleaning head <NUM>. The ultrasonic generator <NUM> (e.g., an ultrasonic power amplifier and function generator) may supply energy to the ultrasonic device <NUM>. The ultrasonic supply line <NUM> (e.g., a flexible acoustic waveguide) may couple the ultrasonic generator <NUM> to the cleaning head <NUM> such that ultrasonic waves <NUM> may be applied from the ultrasonic devices <NUM> to the surface <NUM> of the object <NUM> (e.g., about the cleaning zone <NUM>).

The cleaning medium source <NUM> may be fluidly coupled to the cleaning head <NUM>. The cleaning medium source <NUM> may supply the cleaning medium <NUM> to the cleaning medium dispenser <NUM>. The cleaning medium supply line <NUM> may fluidly couple the cleaning medium source <NUM> to the cleaning head <NUM> such that cleaning medium <NUM> may be provided from the cleaning medium dispenser <NUM> within the vacuum chamber <NUM> (<FIG>) and/or to the surface <NUM> of the object <NUM> (e.g., about the cleaning zone <NUM>).

The vacuum source <NUM> may be fluidly coupled to the cleaning head <NUM>. The vacuum source <NUM> may supply a vacuum airflow <NUM> (e.g., vacuum suction) to the vacuum <NUM>. The vacuum supply line <NUM> may fluidly couple the vacuum source <NUM> to the cleaning head <NUM> such that vacuum suctioning (e.g., vacuum airflow <NUM>) may be applied from the vacuum <NUM> within the vacuum chamber <NUM> and/or to the surface <NUM> of the object <NUM> (e.g., about the cleaning zone <NUM>).

The disclosed system <NUM> may be incorporated into a movable assembly <NUM>. The object <NUM> (e.g., one or more surfaces <NUM> of the object <NUM>) may be cleaned with the cleaning head <NUM>, which may be moved alongside the object <NUM> by the movable assembly <NUM>. A position (e.g., location) of the cleaning head <NUM> with respect to the object <NUM> (e.g., the surface <NUM> of the object <NUM>) and a desired distance between the cleaning head <NUM> and the object <NUM> may be set and/or maintained by the movable assembly <NUM>.

The cleaning medium <NUM> may include any suitable substance and/or material that are able to perform the cleaning action in combination with the ultrasonic waves <NUM> and vacuum airflow <NUM>. The cleaning medium <NUM> may include any cleaning fluid. The cleaning fluid may include a liquid or a gas. As an example, the cleaning medium <NUM> may include liquid water (e.g., hot water and/or cold water). As another example, the cleaning medium <NUM> may include any aqueous solutions (e.g., organic solvents, surfactants, detergents or other chemicals). According to the invention to which this European patent is directed,
the cleaning medium <NUM> is steam (e.g., vaporized water). As another example,
the cleaning medium <NUM> may be air (e.g., forced and/or pressurized air). As another example, the cleaning medium <NUM> may include a blasting media (e.g., solid plastic pellets, sand, gel capsules, liquid CO2, solid CO2, and the like). As yet another example, the cleaning medium <NUM> may include any combination of cleaning fluids and/or blasting media.

Thus, the removal of debris <NUM> is achieved by the combination of the cleaning medium <NUM>, the ultrasonic waves <NUM> and the vacuum airflow <NUM> and, therefore, may be completely non-contact. For example, the cleaning medium dispenser <NUM>, the ultrasonic devices <NUM> and the vacuum <NUM> may be positioned at a distance (e.g., spaced away) from the object <NUM> to be cleaned and do not impose any risk of contamination of the surface <NUM> of the object <NUM>.

In an example implementation, during a cleaning operation, the cleaning medium <NUM> may form droplets and/or thin films on the surface <NUM> of the object <NUM>. The debris <NUM> may be captured, suspended and/or dissolved in the cleaning medium <NUM>. Ultrasonic waves <NUM> delivered to the surface <NUM> by the ultrasonic devices <NUM> may facilitate atomization and/or evaporation of the droplets and/or films and, thus, removal of the debris <NUM> from the surface <NUM> by the vacuum <NUM>.

In a particular, non-limiting example, the disclosed system <NUM> may perform two major types of cleaning operations, a wet cleaning operation or a dry cleaning operation. The wet cleaning operation and the dry cleaning operation may be combined into a unitary cleaning action.

During a wet cleaning operation, the cleaning medium <NUM> may include wet steam jets (e.g., having at least <NUM>% - <NUM>% water) and may form droplets (e.g., water droplets) and/or thin liquid films (e.g., thin films of water) on the surface <NUM> of the object <NUM>. Optionally, the cleaning medium <NUM> may include the addition of cleaning solutions. The debris <NUM> may be dissolved and/or suspended in the cleaning medium <NUM> (e.g., particles of debris <NUM> captured within a liquid envelope). Ultrasonic waves <NUM> delivered to the surface <NUM> by the ultrasonic devices <NUM> may facilitate atomization and/or evaporation of the droplets and/or films and, thus, removal of the debris <NUM> from the surface <NUM> by the vacuum <NUM>.

During a dry cleaning operation, the cleaning medium <NUM> may include dry steam jets (e.g., having less than <NUM>% - <NUM>% water) and may disintegrate the debris <NUM> on the surface <NUM> of the object <NUM>. Ultrasonic waves <NUM> delivered to the surface <NUM> by the ultrasonic devices <NUM> may reduce adhesion of the debris <NUM> to the surface <NUM> and, thus, facilitate removal of the debris <NUM> from the surface <NUM> by the vacuum <NUM>. Referring to <FIG>, in one implementation, the movable assembly <NUM> may be a robotic assembly <NUM>. The robotic assembly <NUM> may provide for automated or semi-automated cleaning of one or more objects <NUM>. For example, the cleaning head <NUM> (e.g., including at least one ultrasonic device <NUM>, at least one cleaning medium dispenser <NUM> and at least one vacuum <NUM>) may be mounted to an end adaptor <NUM> of a robotic arm <NUM> of the robotic assembly <NUM>. The end adaptor <NUM> may be mounted to a movable joint <NUM> located on an end of the robotic arm <NUM> of the robotic assembly <NUM>. The movable joint <NUM> may facilitate positioning of the cleaning head <NUM> in a desired position and orientation approximating the surface <NUM> of the object <NUM> being cleaned. For example, the movable joint <NUM> may include a rotary joint for positioning the cleaning head <NUM> (e.g., positioning of the end adaptor <NUM>) during cleaning of the surface <NUM> and/or articles protruding from the surface <NUM> (e.g., fasteners) of the object <NUM>.

A supply line <NUM> may extend from the cleaning head <NUM> to a cleaning source <NUM> that may, for example, be mounted to a base <NUM> of the robotic assembly <NUM>. The supply line <NUM> may include an ultrasonic supply line <NUM>, a cleaning medium supply line <NUM> and a vacuum supply line <NUM>. Similarly, the cleaning source <NUM> may include an ultrasonic generator <NUM>, a cleaning medium source <NUM> and a vacuum source <NUM>.

Additionally, a fluid injection unit <NUM>, a cleaning filter <NUM> and a contamination-accumulating container <NUM> (e.g., a waste receptacle) may be included in the movable assembly <NUM> (e.g., in the base <NUM> of the robotic assembly <NUM>). The fluid injection unit <NUM> may inject a cleaning solution <NUM> into the cleaning medium supply line <NUM> or to the surface <NUM> of the object <NUM>. The contamination-accumulating container <NUM> may be coupled to the vacuum supply line <NUM> for receiving cleaning medium <NUM> and debris <NUM> (e.g., water vapor, detergent, chemicals, or other materials) that may be suctioned from the surface <NUM> of the object <NUM>.

Referring to <FIG>, in another implementation, the robotic assembly <NUM> may include one or more manufacturing devices <NUM> mounted, for example, on the end adaptor <NUM>. The manufacturing device <NUM> may include a device for performing operations on the object <NUM> (<FIG>). For example, the manufacturing device <NUM> may include one or more devices for machining, drilling, painting, sealing, imaging, testing, inspecting, sensing, and other operations on the object <NUM> (e.g., during fabrication, assembly and/or maintenance). The manufacturing device <NUM> may be coupled via a supply line <NUM> to a power supply/material supply unit <NUM>, for example, at the base <NUM> of the robotic assembly <NUM> for delivery of materials and/or power to the manufacturing device <NUM>.

The supply line <NUM> may deliver lubricant, sealant, coating material, or other materials to the manufacturing device <NUM>. The supply line <NUM> may also deliver electrical power, pressurized air, hydraulic fluid, and other mediums for operating the manufacturing device <NUM>. The cleaning head <NUM> may be employed in the robotic assembly <NUM> to perform a cleaning operation on the object <NUM> prior to or following the performance of one or more manufacturing, inspection, repair, or maintenance operations on the object <NUM> by one or more of the manufacturing devices <NUM>.

Referring to <FIG>, and according to the invention to which this European patent is directed, the cleaning head <NUM> includes a vacuum
chamber <NUM> having an open end <NUM>. For example, a plurality of sidewalls <NUM> may define a partially enclosed vacuum chamber <NUM> having a rectangular cross-sectional shape. As another example, a continuous sidewall <NUM> may define a partially enclosed vacuum chamber <NUM> having an annular cross-sectional shape. The vacuum chamber <NUM> may be sized and configured according to a given cleaning operation and/or application, such as the size of the object <NUM>, the shape of the object <NUM> and/or the complexity of the object <NUM>. Similarly, the size of the cleaning zone <NUM> may be determined by area covered by the cleaning medium <NUM>, the vacuum airflow <NUM> and ultrasonic waves <NUM> (e.g., waves 28a and 28b).

In an example construction, the cleaning head <NUM> may be removably attached to (e.g., detachable from) the movable assembly <NUM> (e.g., the end adaptor <NUM> of the robotic arm <NUM>). In order to facilitate detachment of the cleaning head <NUM> and replacement of a cleaning head <NUM> having the same or a different configuration, the cleaning head <NUM> may include at least one end fitting (not shown). For example, the end fitting may be provided as a quick release mechanism. The quick release mechanism may be provided in any one of a variety of configurations for releasably attaching the cleaning head <NUM> to the supply line <NUM> and/or the movable assembly <NUM> (e.g., the end adaptor <NUM>). The detachable arrangement of the cleaning head <NUM> may facilitate mounting of any one of a variety of different cleaning heads <NUM> having different sizes, shapes, and configurations (e.g., quantity and/or configurations of ultrasonic devices <NUM>, cleaning medium dispensers <NUM> and/or vacuums <NUM>) to correspond to a given cleaning application.

The cleaning head <NUM> includes a plurality of ultrasonic devices <NUM> (identified individually as 20a, 20b, 20c, 20d and 20e). Each ultrasonic device <NUM> may be an air coupled (e.g., non-contact) ultrasonic transducer (e.g., an actuator and a receiver) that converts energy into ultrasound (e.g., sound waves). For example, the ultrasonic device <NUM> may be a piezoelectric transducer that converts electrical energy into sound. Piezoelectric crystals may change size when a voltage is applied, thus applying an alternating current ("AC") across the piezoelectric transducer may cause it to oscillate at a very high frequency and produce very high frequency sound waves (e.g., ultrasonic waves <NUM>). The plurality of ultrasonic devices <NUM> may be configured into an array of ultrasonic devices <NUM>. The array of ultrasonic devices <NUM> may include a geometry that directs and concentrates the ultrasonic waves <NUM> onto particular areas (e.g., cleaning zones <NUM>) on the surface <NUM> of the object <NUM> to be cleaned.

The high frequency ultrasonic vibrations generated by the ultrasonic waves <NUM> may atomize or aerosolize the droplets and/or thin films of cleaning medium <NUM> that are formed on the surface <NUM> of the object <NUM>. The vacuum <NUM> may then collect the atomized cleaning medium <NUM> and debris <NUM> (e.g., particles of debris <NUM>) within the vacuum airflow <NUM>, which may be deposited in the contamination-accumulating container <NUM>.

In addition, the ultrasonic waves <NUM> (e.g., focused energy) may promote and/or facilitate evaporation of the cleaning medium <NUM> from the surface <NUM> of the object <NUM> (e.g., about the cleaning zone <NUM>). This evaporation may result from excitation (e.g., at the molecular level) of the cleaning medium <NUM> on the surface <NUM> of the object <NUM>. This excitation may cause friction and thus turns the acoustic energy from the ultrasonic waves <NUM> into heat. This heat may cause the water molecules of the cleaning medium <NUM> to move apart forming gas.

The ultrasonic waves <NUM> may be modulated, such that the interaction of the modulated ultrasonic waves <NUM> with the object <NUM> and air medium (e.g., air between the ultrasonic devices <NUM> and the surface <NUM> of the object <NUM>) generates desired patterns of ultrasonic vibrations. For example, the ultrasonic devices <NUM> may generate ultrasonic waves <NUM> having different frequencies and/or amplitudes such that when the ultrasonic waves <NUM> impinge on the object <NUM>, desired patterns of ultrasonic vibrations may be generated on the surface <NUM> of the object <NUM> and in the air medium.

The initial patterns generated by the ultrasonic waves <NUM> may be complex but eventually, after many reflections and as the ultrasonic waves <NUM> travel from one boundary to another, a modal pattern may be established at a resonant frequency. There may be many resonant frequencies fairly close together because of the ultrasonic excitation. Removal of the cleaning medium <NUM> and debris <NUM> may often occur at a resonant or a non-resonant situation.

Various types of guided ultrasonic wave modes and stress focal points may be created on the surface <NUM> of the object <NUM> at desired locations (e.g., the cleaning zone <NUM>) by placing, activating and tuning the ultrasonic devices <NUM> to form an acoustically resonating system. The acoustically resonating system may deliver the desired patterns of ultrasonic vibrations to the entire object <NUM>, which, for example, may be fixed with a holding fixture <NUM> (<FIG>). The air coupled ultrasonic devices <NUM>, which are located outside the object <NUM>, may create the desired patterns of ultrasonic vibrations directed about the cleaning zone <NUM>. Focusing ultrasonic stresses may be achieved electronically (e.g., tuning the ultrasonic devices <NUM>) and/or mechanically (e.g., positioning the ultrasonic devices <NUM>). Air-coupled, parametric acoustic arrays (e.g., parametric arrays or phased arrays) of ultrasonic devices <NUM> may be specifically configured to impinge ultrasonic vibrations on complex three-dimensional objects to facilitate atomization of the droplets and thin films of cleaning medium <NUM> containing the debris <NUM>.

As used herein, a parametric array may include a plurality of ultrasonic devices <NUM> (e.g., piezoelectric transducers) configured to produce a narrow primary beam of sound (e.g., ultrasonic waves <NUM>). In general, the larger the dimensions of the parametric array, the narrower the beam. As a general, non-limiting example, the parametric array may be driven at two closely spaced ultrasonic frequencies (e.g., ω<NUM> and ω<NUM>) at high enough amplitudes to produce a difference frequency (e.g., ω<NUM> - ω<NUM>).

As used herein, a phased array may include a plurality of ultrasonic devices <NUM> (e.g., piezoelectric transducers) individually connected so that the signals they transmit or receive may be treated separately or combined as desired. For example, multiple ultrasonic devices <NUM> may be arranged in patterns in a common housing. The patterns may include, but are not limited to, linear, matrix, and/or annular in shape. The ultrasonic devices <NUM> may be pulsed simultaneously or independently of each other in varying patterns to achieve specific beam characteristics.

As illustrated in <FIG>, ultrasonic device 20a, 20b and 20c may be located within the vacuum chamber <NUM>. For example, ultrasonic device 20a may be positioned at a generally central location within the vacuum chamber <NUM> and ultrasonic devices 20b and 20c may be positioned proximate (e.g., at or near) edges of the vacuum chamber <NUM> (e.g., proximate the open end <NUM>. ) Ultrasonic devices 20d and 20e may be located outside of the vacuum chamber <NUM>. For example, ultrasonic devices 20d and 20e may be attached to one or more holding fixtures <NUM>. The holding fixture <NUM> may be attached (e.g., removably attached) to the cleaning head <NUM> and/or end effector <NUM>. Ultrasonic devices 20d and 20e may be positioned at a fixed location on an associated holding fixture <NUM> or may be movable (e.g., manually or electromechanically) relative to the associated holding fixture <NUM>.

For example, the plurality of ultrasonic devices <NUM> (e.g., the array of ultrasonic devices <NUM>) may be tuned and/or positioned to alter wave interference phenomenon in order to create a one or more interference zones or stress focal points (e.g., at the cleaning zones <NUM>) that may be moved around the object <NUM> as position, frequency and/or wave mode are changed. The cleaning zone <NUM> may be moved, through user selection, allowing cleaning at specific points on the surface <NUM> of the object <NUM>.

Specific ultrasonic mode and frequency excitation over a frequency range (e.g., from <NUM> to <NUM>) may be provided, wherein frequency tuning over a selected frequency range may be achieved by optimally positioning the ultrasonic devices <NUM> and/or by modal vibration combinations. How the ultrasonic stresses are focused for effective atomization and/or evaporation of the cleaning medium <NUM> and debris <NUM> from the surface <NUM> of the object <NUM> may depend on the particular cleaning operation. For example, the type of debris <NUM>, the thickness of the debris <NUM>, the structural geometry of the object <NUM>, environmental conditions and the like may affect the configuration of the ultrasonic devices <NUM>.

As an example, the frequency of one or more of the ultrasonic devices <NUM> may be tuned to a particular frequency or frequency range depending upon the particle size of the debris <NUM>. As an example, relatively low frequencies (e.g., below approximately <NUM>) may atomize the cleaning medium <NUM> into a relatively large mist (e.g., approximately <NUM> microns and above). Thus, the mist of atomized cleaning medium <NUM> may capture relatively large particles of debris <NUM> (e.g., approximately <NUM> microns and above). As another example, relatively high frequencies (e.g., above approximately <NUM>) may atomize the cleaning medium <NUM> into a relatively small mist (e.g., approximately <NUM> microns and below). Thus, the mist of atomized cleaning medium <NUM> may capture relatively small particles of debris <NUM> (e.g., approximately <NUM> microns and below).

As another example, the frequency of one or more of the ultrasonic devices <NUM> may be tuned to a particular frequency or frequency range depending upon the size and/or shape of the surface <NUM> to be cleaned. As an example, large and/or generally flat surfaces may have relatively large particles of debris <NUM> (e.g., approximately <NUM> microns and above). Thus, relatively low frequencies (e.g., below approximately <NUM>) may be used to atomize the cleaning medium <NUM> and the debris <NUM> from the surface <NUM>. As another example, small and/or complex surfaces may have relatively small particles of debris <NUM> (e.g., approximately <NUM> microns and below). Thus, relatively high frequencies (e.g., above approximately <NUM>) may be used to atomize the cleaning medium <NUM> and the debris <NUM> from the surface <NUM>.

The ultrasonic devices <NUM> may be configured to generate a variety of different types of ultrasonic waves <NUM> (<FIG>) applied to the surface <NUM> of the object <NUM>, including, but not limited to, longitudinal waves, shear waves, surface waves and/or plate waves. For example, ultrasonic device 20a may generate ultrasonic waves 28a (e.g., longitudinal and/or shear waves) in the object <NUM> and ultrasonic devices 20b, 20c, 20d and 20e may generate ultrasonic waves 28b (e.g., surface and/or plate waves) on the surface <NUM> of the object <NUM>. As another example, ultrasonic devices 20a, 20b and 20c may generate ultrasonic waves 28a (e.g., longitudinal waves and/or shear waves) in the object <NUM> and ultrasonic devices 20d and 20e may generate ultrasonic waves 28b (e.g., surface waves and/or plate waves) on the surface <NUM> of the object <NUM>. Those skilled in the art will appreciate that any individual ultrasonic device <NUM> and/or combination of ultrasonic devices <NUM> (e.g., arrays of ultrasonic devices <NUM>) may be configured to generate any combination of ultrasonic waves <NUM> (e.g., longitudinal waves and/or shear waves in the object <NUM> and/or surface waves and/or plate waves on the surface <NUM> of the object <NUM>).

Additionally, the ultrasonic devices <NUM> may also be used for non-destructive inspection of the object <NUM> and/or structural health monitoring of the object <NUM>. For example, at least two ultrasonic devices <NUM> (e.g., transmitter and receiver) may be positioned above the surface <NUM> of the object <NUM>. The positions of the devices <NUM> may be adjusted relative to each other and relative to and along the surface <NUM> in order to define the directions of sonic propagation at appropriate angles to generate and detect surface and/or plate waves on the surface <NUM>. The generation and detection of the ultrasonic waves <NUM> may depend on several factors including, but not limited to, the elastic properties of the material of the surface <NUM> and the presence of contamination (e.g., debris <NUM>) and water. A reference library of various patterns of the ultrasonic waves <NUM> generated and detected by the ultrasonic devices <NUM> on the reference surfaces may be built and used in non-destructive inspection of the conditions (e.g., cleanliness) of the monitored surface <NUM> of the object <NUM>.

The cleaning medium dispenser <NUM> may be located within the vacuum chamber <NUM> at an orientation sufficient to deliver the cleaning medium <NUM> to the surface <NUM> of the object <NUM>. The cleaning medium dispenser <NUM> may include a nozzle <NUM> fluidly coupled to the cleaning medium supply line <NUM>. The nozzle <NUM> may include a nozzle outlet <NUM> configured to discharge the cleaning medium <NUM> directly into the vacuum chamber <NUM> and/or on the surface <NUM> of the object <NUM> (e.g., within the cleaning zone <NUM>). The cleaning medium <NUM> (e.g., a water spray or steam cloud) may facilitate the removal of debris <NUM> (<FIG>) from one or more surfaces <NUM> of the object <NUM>.

The cleaning medium dispenser <NUM> (e.g., the nozzle <NUM>) may be configured to discharge cleaning medium <NUM> in a manner such that one or more surfaces <NUM> of the object <NUM> may be exposed to the cleaning medium <NUM> for dislodging and removing debris <NUM> from the surface <NUM> of the object <NUM>. For example, the nozzle outlet <NUM> may be configured to discharge cleaning medium <NUM> along a generally axial direction toward one or more surfaces <NUM> of the object <NUM> at the open end <NUM> of the cleaning head <NUM>. However, the nozzle outlet <NUM> may be configured to discharge cleaning medium <NUM> in any one of a variety of directions and/or angles.

Although a single nozzle <NUM> with a single nozzle outlet <NUM> is shown, any number of nozzles <NUM> and/or nozzle outlets <NUM> in any size and location may be provided. For example, a plurality of nozzles <NUM> and/or a plurality of nozzle outlets <NUM> may extend into the vacuum chamber <NUM> at different locations to provide a more uniform distribution of cleaning medium <NUM>. Further, although the nozzle <NUM> is illustrated as being fluidly coupled to an end (e.g., opposite the open end <NUM>) of the vacuum chamber <NUM>, one or more nozzles <NUM> may be included to provide cleaning medium <NUM> from one or more locations along the sidewalls <NUM> of the vacuum chamber <NUM> (e.g., proximate the open end <NUM>).

In an example implementation, the cleaning medium <NUM> may be water (e.g., hot water), the cleaning medium dispenser <NUM> may include a nozzle <NUM> suitable to discharge water (e.g., in the form of a drip, a stream, a spray or a mist), the cleaning medium supply line <NUM> may be a water supply line, and the cleaning medium source <NUM> may be a water source (e.g., water tank). Optionally, the cleaning medium source <NUM> may include a heating mechanism <NUM> (<FIG>) to heat the water to a desired cleaning temperature.

According to the invention to which this European patent is directed, the cleaning medium <NUM> is steam (e.g., wet
steam and/or dry steam), the cleaning medium dispenser <NUM> includes a nozzle <NUM> suitable to discharge steam (e.g., in the form a spray, a mist, or a jet), the cleaning medium supply line <NUM> may be a steam supply line and the cleaning medium source <NUM> is a steam source, namely a water tank and a heating mechanism <NUM> (<FIG>) to generate steam.

For example, the cleaning
head <NUM> may be configured such that a steam jet is discharged from the nozzle outlet <NUM> resulting in the formation of a steam cloud within the vacuum chamber <NUM> and/or on the surface <NUM> of the object <NUM>.

The cleaning medium <NUM> (e.g., steam, hot water, and/or an aqueous cleaning solution) may facilitate the removal of debris <NUM> (<FIG>) from one or more surfaces <NUM> of the object <NUM>. For example, the steam cloud may promote the dislodgement of debris <NUM> (<FIG>) from the surface <NUM> of the object <NUM> by releasing and breaking up bonds between the debris <NUM> and the surface <NUM> of the object <NUM>. The breaking up of the debris <NUM> may result from a plurality of micro-condensations that may occur when relatively tiny hot water vapor molecules contact the relatively cooler debris <NUM>. The micro-condensations may provide energy to break the bonds within the debris <NUM> and bonds between the debris <NUM> and the surface <NUM> of the object <NUM>. The result of the micro-condensations and the breaking of the bonds may be a plurality of relatively small particles of debris <NUM> that may become entrained in water suspension (e.g., within a liquid envelope) in the cleaning medium <NUM> (e.g., the steam cloud).

Additionally, steam may have a relatively low moisture content such as between approximately <NUM> percent and <NUM> percent moisture and, more preferably, between approximately <NUM> percent and <NUM> percent moisture which may enable the surface <NUM> of the object <NUM> to dry relatively quickly. Further, the low moisture content of steam may result in relatively low water usage during cleaning operations.

The flow of cleaning medium <NUM> into the vacuum chamber <NUM> and/or to the surface <NUM> of the object <NUM> may be provided by the cleaning medium supply line <NUM>. In an example construction, the cleaning medium supply line <NUM> may extend from the cleaning medium source <NUM> (e.g., at the base <NUM> of the robotic assembly <NUM>) (<FIG>) to the cleaning head <NUM>. Thermal insulation may cover a substantial portion of the cleaning medium supply line <NUM> to preserve the temperature of the cleaning medium <NUM> (e.g., steam) within the cleaning medium supply line <NUM> and as a safety precaution for personnel using the system <NUM>. The flow of cleaning medium <NUM> from the cleaning medium supply line <NUM> into the cleaning medium dispenser <NUM> (e.g., the nozzle <NUM>) may be controlled by a valve (e.g., a steam valve or water valve (not shown)) that may be mounted to the cleaning medium supply line <NUM> and/or to the cleaning head <NUM>.

The temperature and/or the pressure of the cleaning medium <NUM> (e.g., water temperature and/or pressure or steam temperature and/or pressure) may be regulated, adjusted and/or otherwise controlled to correspond to a given cleaning operation. For example, the temperature may of the cleaning medium <NUM> be controlled to provide cleaning medium <NUM> at a temperature that may avoid heat damage to the material composition of the object <NUM> and/or the surface <NUM> being cleaned. Similarly, the pressure of the cleaning medium <NUM> may be regulated (e.g., by means of the valve) such that cleaning medium <NUM> may be discharged from the nozzle outlet <NUM> in a manner that the velocity of the cleaning medium <NUM> is high enough to contact the surface <NUM> of the object <NUM> prior to atomization of the cleaning medium <NUM> (e.g., by the ultrasonic waves <NUM>) and vacuum suctioning of the cleaning medium <NUM> and any collected debris <NUM> into the vacuum <NUM> (<FIG>). Control of cleaning medium <NUM> from the cleaning medium source <NUM> (<FIG>) may be preprogrammed, for example, into the movable assembly <NUM>.

The vacuum <NUM> (<FIG>) may be fluidly coupled to the vacuum supply line <NUM> (e.g., a vacuum hose) to provide vacuum suctioning (e.g., vacuum airflow <NUM>) within the vacuum chamber <NUM> and/or to the surface <NUM> of the object <NUM>. The corresponding vacuum airflow <NUM> may be directed to the vacuum source <NUM> (<FIG>) through one or more vacuum inlet manifolds <NUM>. The vacuum inlet manifold <NUM> may be located inside the vacuum chamber <NUM>.

The size, quantity, location, relative position, orientation angle, and distance from the surface <NUM> of the object <NUM> may be considered when sizing and configuring the cleaning head <NUM> for a given cleaning operation. Similarly, the overall size, shape, and configuration of the cleaning head <NUM> and/or the vacuum chamber <NUM> may also be configured complementary to the size, shape and configuration of the object <NUM> to be cleaned by the cleaning head <NUM>.

Referring again to <FIG>, in another implementation, the system <NUM> may also include the fluid injection unit <NUM> for injecting cleaning solution <NUM> into the cleaning medium supply line <NUM> for mixing with the cleaning medium <NUM> that is provided to the cleaning head <NUM> (e.g., to the cleaning medium dispenser <NUM>).

The cleaning solution <NUM> of the fluid injection unit <NUM> may be provided in a composition that may promote or expedite the cleaning of the object <NUM>. For example, the cleaning solution <NUM> may include detergent and/or chemicals for injection into the cleaning medium supply line <NUM>, which results in a mixture of molecules of detergent and/or chemicals in the cleaning medium <NUM>. The detergent and/or chemicals may include, but are not limited to, solvents for breaking up or dissolving certain type of debris <NUM> into smaller debris particles. The detergent and/or chemicals may surround the debris <NUM> once the debris particles are broken loose from the surface <NUM> of the object <NUM>. The detergent and/or chemicals may encapsulate the debris particles and prevent the debris particles from re-attaching to one another and/or re-bonding to the surface <NUM> of the object <NUM>.

For example, the cleaning solution <NUM> may include a composition for enhancing the cleaning of certain types of debris <NUM>, such as water- and/or oil-based fluids (e.g., hydraulic fluids and greases). The cleaning solution <NUM> may be injected into the cleaning medium <NUM> in a predetermined amount (e.g., upon activation of a release valve). The mixture of detergent and chemical molecules in the cleaning medium <NUM> (e.g., the steam cloud or hot water) may penetrate the relatively cooler debris <NUM> on the surface <NUM> of the object <NUM> and may further facilitate dislodgment of the debris <NUM>. In this regard, the cleaning solution <NUM> may include any one of a variety of other compositions, without limitation, for expediting or enhancing the cleaning of certain types of debris <NUM>.

Alternatively, the cleaning solution <NUM> (e.g., detergent and/or chemicals) may be applied directly to the surface <NUM> of the object <NUM>.

Referring to <FIG>, in another implementation of the cleaning head <NUM>, ultrasonic devices <NUM> (referred to individually as ultrasonic devices 20f and <NUM>) may be located only outside of the vacuum chamber <NUM>. For example, ultrasonic devices 20f and <NUM> may be attached to one or more holding fixtures <NUM>. The holding fixture <NUM> may be attached (e.g., removably attached) to the end effector <NUM>. Ultrasonic devices 20f and <NUM> may be positioned at a fixed location on an associated holding fixture <NUM> or may be movable (e.g., manually or electromechanically) relative to the associated holding fixture <NUM>. Ultrasonic devices 20f and <NUM> may generate ultrasonic waves <NUM> (e.g., longitudinal waves and/or shear waves) in the object <NUM>.

The cleaning medium dispenser <NUM> may deliver cleaning medium <NUM> (e.g., steam) to the surface <NUM> of the object <NUM> to dislodge the debris <NUM> (<FIG>). The ultrasonic waves <NUM> (e.g., longitudinal and/or shear waves) may atomize the cleaning medium <NUM> holding the debris <NUM> (e.g., particles of debris <NUM>), which may them be collected by the vacuum airflow <NUM>.

Referring to <FIG>, in another aspect, the disclosed system may include a holding fixture <NUM> configured to hold and/or support the object <NUM>. For example, the holding fixture <NUM> may be a component assembly fixture used to hold the object <NUM> during a fabrication, assembly and/or maintenance operation (e.g., as part of an assembly line) and during a cleaning operation. As another example, the holding fixture <NUM> may be used to hold the object <NUM> only during a cleaning operation. As yet another example, the holding fixture <NUM> may be a part of the object <NUM>.

At least one ultrasonic device <NUM> may be coupled to the holding fixture <NUM>. The ultrasonic devices <NUM> may deliver ultrasonic waves <NUM> to the object <NUM> through the holding fixture <NUM>. At least one ultrasonic generator <NUM> may supply energy to the ultrasonic devices <NUM>. An ultrasonic supply line <NUM> may electrically couple the ultrasonic generator <NUM> to the ultrasonic devices <NUM> such that ultrasonic waves <NUM> may be applied through the entire object <NUM>.

Each ultrasonic device <NUM> may be an ultrasonic transducer that converts energy into ultrasound (e.g., sound waves). For example, the ultrasonic device <NUM> may be a piezoelectric transducer that converts electrical energy into sound.

During a cleaning operation, the cleaning head <NUM> may be positioned in close proximity to the surface <NUM> of the object <NUM>, for example by the robotic assembly <NUM>. The cleaning medium <NUM> may be delivered to the surface <NUM> of the object <NUM> (e.g., about the cleaning zone <NUM>) from the cleaning medium dispenser <NUM> to dislodge debris <NUM> on the surface <NUM>. The ultrasonic waves <NUM> generated by the ultrasonic devices <NUM> in the cleaning head <NUM> and delivered to the surface <NUM> of the object <NUM> may work in concert with the ultrasonic waves <NUM> generated by the ultrasonic devices <NUM> of the holding fixture <NUM> and delivered into the object <NUM> to atomize the cleaning medium <NUM>. The vacuum <NUM> may vacuum the atomized cleaning medium <NUM> and the dislodged debris <NUM> (e.g., debris particles held within the cleaning medium <NUM>).

As used herein, close proximity may include a position close to the surface <NUM> of the object <NUM> without touching the object <NUM>. As an example, close proximity may include positions of at most approximately <NUM> inches from the surface <NUM>. As another example, close proximity may include positions of at most approximately <NUM> inches from the surface <NUM>. As another example, close proximity may include positions of at most approximately <NUM> inches from the surface <NUM>. As another example, close proximity may include positions of at most approximately <NUM> inch from the surface <NUM>. As yet another example, close proximity may include positions as close to the surface <NUM> as possible without contacting the surface <NUM>.

Those skilled in the art will appreciate that the proximity to the surface <NUM> of the object <NUM> may depend upon the size, power and/or configuration of the ultrasonic devices <NUM>, the cleaning medium dispenser <NUM>, the vacuum <NUM>, the ultrasonic devices <NUM> and/or the ultrasonic devices <NUM> in order to effectively perform a cleaning operation.

Referring to <FIG>, in an example implementation, the holding fixture <NUM> may include at least one object holding fixture <NUM> configured to engage at least a portion (e.g., an edge) of the object <NUM> to secure the object <NUM> to the holding fixture <NUM> and fix the position of the object <NUM>. For example, each object holding fixture <NUM> may include an edge holding fixture <NUM> to engage at least one edge of the object <NUM> (e.g., an aircraft wing panel).

An ultrasonic device <NUM> may be coupled to each of the object holding fixtures <NUM> to transfer ultrasonic waves <NUM> (e.g., vibrations) (<FIG>) through the object holding fixtures <NUM> and into the object <NUM>. Each ultrasonic device <NUM> may be physically coupled to the object holding fixtures <NUM> (e.g., a contact ultrasonic transducer) or air coupled to the object holding fixtures <NUM> (e.g., a non-contact ultrasonic transducer). The object holding fixtures <NUM>, including any edge holding fixtures <NUM>, may be acoustically coupled to the holding fixture <NUM> and the object <NUM> such that the ultrasonic waves <NUM> applied to the object holding fixtures <NUM> sufficiently transfer between and through the holding fixture <NUM>, the object holding fixtures <NUM> and into the object <NUM>.

As used herein, acoustically coupled means that all parts and/or components of the holding fixture <NUM> are connected together such that the entire construction is acoustically available (e.g., an acoustically resonating system) for effective transmission and propagation of ultrasonic waves <NUM>. For example, the holding fixture <NUM> may be constructed such that no gaps occur between components and the propagation of ultrasonic waves <NUM> is not lost through component and/or surface interfaces.

Referring to <FIG>, in another implementation, the object <NUM> may be mounted to a support base <NUM>. The object <NUM> may be in contact with the support base <NUM> or may be spaced apart a predetermined distance from the support base <NUM>. The holding fixture <NUM> may include at least one support base holding fixture <NUM> configured to engage at least a portion of the support base <NUM> to secure the support base <NUM> to the holding fixture <NUM> and fix the position of the object <NUM>.

An ultrasonic device <NUM> may be coupled to each of the support base holding fixtures <NUM> to transfer ultrasonic waves <NUM> (<FIG>) through the support base holding fixtures <NUM>, through the support base <NUM> and into the object <NUM>. The ultrasonic devices <NUM> may be physically coupled to the support base holding fixtures <NUM> or air coupled to the support base holding fixtures <NUM>. The support base holding fixtures <NUM> may be acoustically coupled to the holding fixture <NUM> and the support base <NUM> such that the ultrasonic waves <NUM> applied to the support base holding fixtures <NUM> sufficiently transfer between and through the holding fixture <NUM>, the support base holding fixtures <NUM>, the support base <NUM> and into the object <NUM>. Any object holding fixtures <NUM>, including any edge holding fixtures <NUM>, may similarly be acoustically coupled to the holding fixture <NUM>.

Referring to <FIG>, in yet another example construction, the object <NUM> may be mounted to the support base <NUM> and the holding fixture <NUM> may include at least one object holding fixture <NUM> and at least one support base holding fixture <NUM> to secure the support base <NUM> and the object <NUM> to the holding fixture <NUM> and fix the position of the object <NUM> with respect to the cleaning head <NUM> and/or the movable assembly <NUM> (e.g., the robotic assembly <NUM>).

An ultrasonic device <NUM> may be coupled to each of the object holding fixtures <NUM> and each of the support base holding fixtures <NUM> to transfer ultrasonic waves <NUM> (<FIG>) through the object holding fixtures <NUM> and the support base holding fixtures <NUM>, through the support base <NUM> and into the object <NUM>. The ultrasonic devices <NUM> may be physically coupled to the object holding fixtures <NUM> and the support base holding fixtures <NUM> or air coupled to the object holding fixtures <NUM> and the support base holding fixtures <NUM>. The object holding fixtures <NUM> and the support base holding fixtures <NUM> may be acoustically coupled to the holding fixture <NUM> and the support base <NUM> such that the ultrasonic waves <NUM> applied to the object holding fixtures <NUM> and the support base holding fixtures <NUM> sufficiently transfer between and through the holding fixture <NUM>, the object holding fixtures <NUM>, the support base holding fixtures <NUM>, the support base <NUM> and into the object <NUM>.

The object holding fixtures <NUM> and/or the support base holding fixtures <NUM> may be integral to the holding fixture <NUM> or may be installed on or connected to the holding fixture <NUM>. The ultrasonic generator <NUM> (<FIG>) may be integral to the holding fixture <NUM> or may be remote and electrically coupled to the ultrasonic devices <NUM>.

Thus, in concert with the ultrasonic devices <NUM>, the object holding fixtures <NUM> and/or the support base holding fixtures <NUM> may form an acoustically resonating system that delivers ultrasonic waves <NUM> (e.g., vibrations) into and through the entire object <NUM>. A plurality of ultrasonic devices <NUM> may be arranged in any configuration (e.g., in an array of ultrasonic devices <NUM>). Each ultrasonic device <NUM> may have a fixed position or may be movable with respect to the holding fixture <NUM>, the object holding fixtures <NUM> and/or the support base holding fixtures <NUM>. For example, the position, orientation and/or location of the ultrasonic devices <NUM> may be manually movable or electromechanically movable. By placing, activating and tuning the ultrasonic devices <NUM>, various types of guided ultrasonic waves <NUM> may be created on the surface <NUM> of the object <NUM> at desired locations (e.g., cleaning zones <NUM>). For example, the ultrasonic waves <NUM> may create acoustic streaming within the cleaning medium <NUM> (e.g., movement of the cleaning fluid in response to the ultrasonic waves <NUM>).

Referring to <FIG>, in another aspect, the disclosed system may include holding fixture <NUM> configured to hold and/or support the object <NUM> and at least one ultrasonic device <NUM> coupled to the holding fixture <NUM>. The ultrasonic devices <NUM> may deliver ultrasonic waves <NUM> to the object <NUM> through the holding fixture <NUM>. At least one ultrasonic generator <NUM> may supply energy to the ultrasonic devices <NUM>. An ultrasonic supply line <NUM> may couple the ultrasonic generator <NUM> to the ultrasonic devices <NUM> such that ultrasonic waves <NUM> may be applied through the entire object <NUM>.

At least one ultrasonic device <NUM> may be attached to the holding fixture <NUM>. The ultrasonic devices <NUM> may deliver ultrasonic waves <NUM> to the object <NUM>. At least one ultrasonic generator <NUM> may supply energy to the ultrasonic devices <NUM>. An ultrasonic supply line <NUM> may couple the ultrasonic generator <NUM> to the ultrasonic devices <NUM> such that ultrasonic waves <NUM> may be applied to the surface <NUM> of the object <NUM>. The ultrasonic generator <NUM> may be integral to the holding fixture <NUM> or may be remote and coupled to the ultrasonic devices <NUM>.

Each ultrasonic device <NUM> and each ultrasonic device <NUM> may be an ultrasonic transducer that converts energy into ultrasound. For example, the ultrasonic device <NUM> and ultrasonic device <NUM> may be a piezoelectric transducer that converts electrical energy into sound.

The cleaning head <NUM> may include only the cleaning medium dispenser <NUM> and the vacuum <NUM>. During a cleaning operation, the cleaning head <NUM> may be positioned in close proximity to (e.g., close to but not in contact with) the surface <NUM> of the object <NUM>, for example by the movable assembly <NUM> (e.g., the robotic assembly <NUM>). The cleaning medium <NUM> may be delivered to the surface <NUM> of the object <NUM> (e.g., about the cleaning zone <NUM>) from the cleaning medium dispenser <NUM> to dislodge debris <NUM> on the surface <NUM>. The ultrasonic waves <NUM> generated by the ultrasonic devices <NUM> of the holding fixture <NUM> and delivered into the object <NUM> may work in concert with the ultrasonic waves <NUM> generated by the ultrasonic devices <NUM> and delivered to the surface <NUM> of the object <NUM> to atomize the cleaning medium <NUM>. The vacuum <NUM> may vacuum the atomized cleaning medium <NUM> and the dislodged debris <NUM> (e.g., debris particles held within the cleaning medium <NUM>).

Referring to <FIG>, in an example implementation, the object <NUM> may be mounted to the support base <NUM>. The holding fixture <NUM> may include at least one support base holding fixture <NUM> to engage at least a portion of the support base <NUM> to secure the support base <NUM> to the holding fixture <NUM> and fix the position of the object <NUM>. The holding fixture <NUM> may include at least one object holding fixture <NUM> to engage at least a portion (e.g., an edge) of the object <NUM> to secure the object <NUM> fix the position of the object <NUM>.

An ultrasonic device <NUM> may be coupled to each of the support base holding fixtures <NUM> to transfer ultrasonic waves <NUM> (<FIG>) through the support base holding fixtures <NUM>, through the support base <NUM> and into the object <NUM>. The ultrasonic devices <NUM> may be physically coupled to the support base holding fixtures <NUM> or air coupled to the support base holding fixtures <NUM>. The support base holding fixtures <NUM> may be acoustically coupled to the holding fixture <NUM> and the support base <NUM> such that the ultrasonic waves <NUM> applied to the support base holding fixtures <NUM> sufficiently transfer between and through the holding fixture <NUM>, the support base holding fixtures <NUM>, the support base <NUM> and into the object <NUM>. Similarly, the object holding fixtures <NUM>, including any edge holding fixtures <NUM>, may be acoustically coupled to the holding fixture <NUM>.

Each ultrasonic device <NUM> may be an air coupled (e.g., non-contact) ultrasonic transducer. One or more ultrasonic devices <NUM> may be attached to the holding fixture <NUM>, for example, to the object holding fixtures <NUM>, by one or more ultrasonic device holding fixtures <NUM>. A plurality of ultrasonic devices <NUM> may be positioned and/or arranged in any configuration (e.g., in an array of ultrasonic devices <NUM>) set apart from the cleaning head <NUM>. The ultrasonic device holding fixture <NUM> may provide for position adjustability of the ultrasonic devices <NUM>. For example, the ultrasonic devices <NUM> may be positioned on opposing sides of the location of the cleaning head <NUM> and may move along with the cleaning head <NUM> during a cleaning operation.

Referring to <FIG>, the ultrasonic device holding fixture <NUM> may be movably connected to the holding fixture <NUM>. The ultrasonic holding fixture <NUM> may provide for movement of the ultrasonic devices <NUM> along at least two axes. For example, the ultrasonic device holding fixture <NUM> may be movably connected to the object holding fixtures <NUM> and movable along an X-axis (e.g., in the direction of arrow <NUM>). The ultrasonic devices <NUM> may be movably connected to the ultrasonic device holding fixture <NUM> and movable along a Y-axis (e.g., in the direction of arrow <NUM>).

The ultrasonic device holding fixture <NUM> and the ultrasonic devices <NUM> may be manually movable or may be automatically or semi-automatically movable (e.g., by an electromechanical drive mechanism (not shown)).

Referring to <FIG>, in an example implantation, the cleaning head <NUM> may include the vacuum chamber <NUM> having an open end <NUM>. The size of the cleaning zone <NUM> may be determined by area covered by the cleaning medium <NUM>, the vacuum airflow <NUM> and ultrasonic waves <NUM> and/or ultrasonic waves <NUM>. The cleaning medium dispenser <NUM> may be located within the vacuum chamber <NUM> at an orientation sufficient to deliver the cleaning medium <NUM> to the surface <NUM> of the object <NUM>. The vacuum <NUM> (<FIG>) may be fluidly coupled to the vacuum supply line <NUM> to provide vacuum suctioning (e.g., vacuum airflow <NUM>) within the vacuum chamber <NUM> and/or to the surface <NUM> of the object <NUM>.

The ultrasonic devices <NUM> and ultrasonic devices <NUM> (<FIG>) may be configured to generate a variety of different types of ultrasonic waves <NUM> applied into the object <NUM> and ultrasonic waves <NUM> applied to the surface <NUM> of the object <NUM>, respectively, including, but not limited to, longitudinal waves, shear waves, surface waves and/or plate waves. For example, ultrasonic device <NUM> may generate longitudinal and/or shear waves <NUM> in the object <NUM> and ultrasonic devices <NUM> may generate surface and/or plate waves <NUM> on the surface <NUM> of the object <NUM>.

Those skilled in the art will appreciate that any individual ultrasonic device <NUM>, ultrasonic device <NUM>, ultrasonic device <NUM> and/or combinations of ultrasonic devices <NUM>, <NUM> and <NUM> (<FIG>) may be configured (e.g., tuned and positioned) to generate any combination of guided ultrasonic waves (e.g., longitudinal waves and/or shear waves in the object <NUM> and/or surface waves and/or plate waves on the surface <NUM> of the object <NUM>).

For example, the different types of ultrasonic waves <NUM>, ultrasonic waves <NUM> and ultrasonic waves <NUM> (<FIG>) (e.g., longitudinal waves, shear waves, surface waves and/or plate waves) may be generated by adjusting the angles of incidence of the ultrasonic devices <NUM>, ultrasonic devices <NUM> and ultrasonic devices <NUM> (<FIG>) relative to the surface <NUM> of the object <NUM>. As an example, positioning (e.g., rotating) the ultrasonic device approximately <NUM>° from normal (e.g., from the plane of the surface <NUM>) may generate plate waves perpendicular to and on the surface <NUM> of the object <NUM>. As another example, positioning (e.g., rotating) the ultrasonic device approximately <NUM>° from normal (e.g., parallel to the plane of the surface <NUM>) may generate longitudinal waves in the object <NUM>. As another example, shear waves may be generated under any angle of incidence and may propagate perpendicularly relative to the wave into the object <NUM>. As yet another example, surface waves may be generated under any angle of incidence and may propagate concentrically (e.g., elliptically) on the surface <NUM> of the object <NUM>.

Referring to <FIG> and <FIG>, in an example implementation, one or more three-dimensional cleaning zones <NUM> (e.g., an ultrasonic interaction volume <NUM>) may be formed around a complex object <NUM> (e.g., a mounting clip) by the interference of a plurality of focused ultrasonic waves.

As an example and best illustrated in <FIG>, a plurality of air coupled ultrasonic devices <NUM> (e.g., such as the ultrasonic devices <NUM> shown and described in <FIG>) may be located in relative close proximity to (e.g., between approximately <NUM> and <NUM> inches from) the object <NUM>. The cleaning head <NUM> (e.g., such as the cleaning head <NUM> shown and described in <FIG>) may be located in relative close proximity (e.g., between approximately <NUM> and <NUM> inches from) to the object <NUM>. The cleaning head <NUM> may deliver cleaning medium <NUM> (e.g., steam) to one or more surfaces <NUM> of the object <NUM> to dislodge debris <NUM> from the surfaces <NUM> of the object <NUM>. The ultrasonic devices <NUM> may generate ultrasonic waves 128a (e.g., longitudinal waves and/or shear waves in the object <NUM>) and ultrasonic waves 128b (e.g., plate waves and/or shear waves on the surface <NUM> of the object <NUM>) to atomize the cleaning medium <NUM> and debris <NUM> (e.g., debris particles retained by the cleaning medium <NUM>). The vacuum <NUM> may provide vacuum suctioning (e.g., vacuum airflow <NUM>) within the vacuum chamber <NUM> and/or to the surface <NUM> of the object <NUM> to remove the atomized cleaning medium <NUM> and debris <NUM>.

The plurality of ultrasonic devices <NUM> (e.g., an array of ultrasonic device <NUM>) may emit the ultrasonic waves 128a and 128b, which are focused toward the object <NUM> and interfere with each other at the object <NUM>. The interfering ultrasound waves 128a and 128b may form the ultrasound interaction volume <NUM> around the object <NUM>, which generates the longitudinal waves and/or shear waves in the object <NUM> and the plate waves and/or shear waves on the surface <NUM> of the object <NUM>.

As another example (not shown), the object <NUM> (e.g., having a relatively complex three-dimensional surface <NUM>) may be mounted to a holding fixture (e.g., the holding fixture <NUM> shown and described in <FIG>). A plurality of ultrasonic devices <NUM> may generate ultrasonic waves <NUM> directed to the object <NUM>. A plurality of ultrasonic devices (e.g., ultrasonic devices <NUM> shown and described in <FIG>) may generate ultrasonic waves <NUM> directed through the holding fixture <NUM> and into the object <NUM>. The interference of ultrasonic waves <NUM> and ultrasonic waves <NUM> may generate the longitudinal waves and/or shear waves in the object <NUM> and the plate waves and/or shear waves on the surface <NUM> of the object <NUM> to atomize the cleaning medium <NUM> and debris <NUM> (e.g., debris particles retained by the cleaning medium <NUM>). The vacuum <NUM> may provide vacuum suctioning (e.g., vacuum airflow <NUM>) within the vacuum chamber <NUM> and/or to the surface <NUM> of the object <NUM> to remove the atomized cleaning medium <NUM> and debris <NUM>.

The plurality of ultrasonic devices <NUM> (e.g., an array of ultrasonic device <NUM>) may emit the ultrasonic waves <NUM> and the plurality of ultrasonic devices <NUM> (e.g., an array of ultrasonic devices <NUM>) may emit the ultrasonic waves <NUM>, which are focused toward the object <NUM> and interfere with each other at the object <NUM>. The interfering ultrasound waves <NUM> and <NUM> may form the ultrasound interaction volume <NUM> around the object <NUM>, which generates the longitudinal waves and/or shear waves in the object <NUM> and the plate waves and/or shear waves on the surface <NUM> of the object <NUM>.

As yet another example and best illustrated in <FIG>, a plurality of air coupled ultrasonic devices <NUM> (e.g., such as the ultrasonic devices <NUM> shown and described in <FIG>) may be located in relative close proximity to the object <NUM>. The cleaning head <NUM> (e.g., such as the cleaning head <NUM> shown and described in <FIG>) may be located in relative close proximity to the object <NUM>. The cleaning head <NUM> may deliver cleaning medium <NUM> (e.g., steam) to one or more surfaces <NUM> of the object <NUM> to dislodge debris <NUM> from the surfaces <NUM> of the object <NUM>. The ultrasonic devices <NUM> may generate ultrasonic waves <NUM> directed to the object <NUM> (e.g., longitudinal waves and/or shear waves in the object <NUM>). A plurality of ultrasonic devices <NUM> located with the cleaning head <NUM> (e.g., the ultrasonic devices <NUM> shown and described in <FIG>) may generate ultrasonic waves <NUM> directed to the object <NUM> (e.g., surface waves and/or plate waves on the surface of the object <NUM>). The interference of ultrasonic waves <NUM> and ultrasonic waves <NUM> may generate the longitudinal waves and/or shear waves in the object <NUM> and the plate waves and/or shear waves on the surface <NUM> of the object <NUM> to atomize the cleaning medium <NUM> and debris <NUM> (e.g., debris particles retained by the cleaning medium <NUM>). The vacuum <NUM> may provide vacuum suctioning (e.g., vacuum airflow <NUM>) within the vacuum chamber <NUM> and/or to the surface <NUM> of the object <NUM> to remove the atomized cleaning medium <NUM> and debris <NUM>.

Referring to <FIG> and <FIG>, the disclosed system <NUM> may be configured to clean one or more confined surfaces <NUM> (e.g., interior surfaces) of an object <NUM>. For example, the system <NUM> may be configured to clean interior surfaces <NUM> of the object <NUM>, such as those located within a confined space <NUM> within the interior of the object <NUM> (e.g., interior surfaces of a wing box of an airplane fuel tank).

Referring to <FIG>, in another implementation, the disclosed system <NUM> may include a handheld cleaning head <NUM>. The cleaning head <NUM> (e.g., the cleaning head <NUM> shown and described in <FIG>) may include at least one cleaning medium dispenser <NUM> to deliver cleaning medium <NUM> to the surface <NUM> of the object <NUM>, at least one air coupled ultrasonic device <NUM> to emit ultrasonic waves <NUM> to the surface <NUM> of the object <NUM> and at least one vacuum <NUM> to provide a vacuum airflow <NUM> to the surface <NUM> of the object <NUM>.

The movable assembly <NUM> may be one or more cart assemblies <NUM>. The cart assembly <NUM> may house the ultrasonic generator <NUM>, the cleaning medium source <NUM> and the vacuum source <NUM>. The cleaning head <NUM> may be functionally coupled to the cart assembly <NUM> by the supply line <NUM>. For example, the ultrasonic supply line <NUM> may be coupled to the ultrasonic devices <NUM>, the cleaning medium supply line <NUM> may be fluidly coupled to the cleaning medium dispenser <NUM> and the vacuum supply line <NUM> may be fluidly coupled to the vacuum <NUM>.

During a cleaning operation, an operator <NUM> may be located within the confined space <NUM> and the cleaning head <NUM> may be introduced within the confined space <NUM>, for example through an access port <NUM> in the object <NUM>. The cleaning head <NUM> may be manually positioned in relatively close proximity to the surface <NUM> of the object <NUM> to be cleaned. The effective position of the cleaning head <NUM> relative to the surface <NUM> may be determined visually. For example, the effective position of the cleaning head <NUM> relative to the surface <NUM> may be determined by when the cleaning medium <NUM> and debris <NUM> begin to and/or fully atomize from the surface <NUM>. Optionally, the operator <NUM> may be positioned on an ultrasonic acoustic absorber <NUM> to maintain an acoustically resonate system and protect the operator <NUM> from ultrasonic vibrations.

A plurality of ultrasonic devices <NUM> (e.g., an array of ultrasonic devices <NUM>) may emit ultrasonic waves <NUM>, for example from the cleaning head <NUM>, directed toward the surface <NUM> and into the object <NUM>. The ultrasonic waves <NUM> may be focused toward the surface <NUM> of the object <NUM> and generates the longitudinal waves and/or shear waves in the object <NUM> and/or the plate waves and/or shear waves on the surface <NUM> of the object <NUM> (e.g., ultrasonic vibrations in the object <NUM>) to atomize the cleaning medium <NUM> and debris <NUM> (e.g., debris particles retained by the cleaning medium <NUM>). The vacuum <NUM> may vacuum the atomized cleaning medium <NUM> and debris <NUM>.

Optionally, a plurality of air coupled ultrasonic devices <NUM> (e.g., the ultrasonic devices shown and described in <FIG>) may be located in relatively close proximity to the surface <NUM> of the object <NUM>. For example, the ultrasonic devices <NUM> may be positioned generally opposite the location of the cleaning head <NUM> and the ultrasonic devices <NUM> (e.g., an opposing surface <NUM>). The ultrasonic devices <NUM> may be connected to one or more ultrasonic device holding fixtures <NUM>. The ultrasonic holding fixtures <NUM> may provide for manual or electromechanical movement and positioning of the ultrasonic devices <NUM> relative to the object <NUM>, such that the ultrasonic devices <NUM> may move alone with the cleaning head <NUM>.

A plurality of ultrasonic devices <NUM> (e.g., an array of ultrasonic devices <NUM>) may emit ultrasonic waves <NUM> directed toward the surface <NUM> and into the object <NUM>. A plurality of ultrasonic devices <NUM> (e.g., an array of ultrasonic devices <NUM>) may emit ultrasonic waves <NUM> toward the opposing surface <NUM> and into the object <NUM>. The ultrasonic waves <NUM> and the ultrasonic waves <NUM> may be focused toward the surface <NUM> of the object <NUM> and interfere with each other about the cleaning zone <NUM> (<FIG>) of the object <NUM>. The interfering ultrasound waves <NUM> and <NUM> may generates the longitudinal waves and/or shear waves in the object <NUM> and/or the plate waves and/or shear waves on the surface <NUM> of the object <NUM> (e.g., ultrasonic vibrations in the object <NUM>) to atomize the cleaning medium <NUM> and debris <NUM> (e.g., debris particles retained by the cleaning medium <NUM>). The vacuum <NUM> may vacuum the atomized cleaning medium <NUM> and debris <NUM>.

Referring to <FIG>, in another implementation, the cleaning head <NUM> may be mounted to a telescopic boom assembly <NUM>. The cleaning head <NUM> (e.g., the cleaning head <NUM> shown and described in <FIG>) may include at least one cleaning medium dispenser <NUM> to deliver cleaning medium <NUM> to the surface <NUM> of the object <NUM>, at least one air coupled ultrasonic device <NUM> to emit ultrasonic waves <NUM> to the surface <NUM> of the object <NUM> and at least one vacuum <NUM> to provide a vacuum airflow <NUM> to the surface <NUM> of the object <NUM>.

The movable assembly <NUM> may be one or more cart assemblies <NUM> and the telescopic boom assembly <NUM>. The cart assembly <NUM> may house the ultrasonic generator <NUM>, the cleaning medium source <NUM> and the vacuum source <NUM>. The cleaning head <NUM> may be functionally coupled to the cart assembly <NUM> by the supply line <NUM>. For example, the ultrasonic supply line <NUM> may be electrically coupled to the ultrasonic devices <NUM>, the cleaning medium supply line <NUM> may be fluidly coupled to the cleaning medium dispenser <NUM> and the vacuum supply line <NUM> may be fluidly coupled to the vacuum <NUM>.

The telescopic boom assembly <NUM> may be configured to automatically or semi-automatically move and position the cleaning head <NUM> with respect to the surface <NUM> to be cleaned within the confined space <NUM>. The telescopic boom assembly <NUM> may be rotatable and articulated. For example, the telescopic boom assembly <NUM> may include a riser stand <NUM> and at least one telescopic arm <NUM> movably connected to the riser stand <NUM>. The cleaning head <NUM> may be connected to an end of the telescopic arm <NUM>, for example at an end effector <NUM>. An actuator <NUM> may automatically adjust the position of the cleaning head <NUM> by extending and/or retracting the telescopic arm <NUM>.

During a cleaning operation, the telescopic arm <NUM> of the telescopic boom assembly <NUM> and the cleaning head <NUM> may be located within the confined space <NUM>, for example introduced within the confined space <NUM> through the access port <NUM> in the object <NUM>. The cleaning head <NUM> may be automatically or semi-automatically positioned in relative close proximity to the surface <NUM> of the object <NUM> to be cleaned, for example by actuating the telescopic arm <NUM> and/or the end effector <NUM>.

A plurality of ultrasonic devices <NUM> (e.g., an array of ultrasonic devices <NUM>) may emit ultrasonic waves <NUM>, for example from the cleaning head <NUM>, directed toward the surface <NUM> and into the object <NUM>. The ultrasonic waves <NUM> may be focused toward the surface <NUM> of the object <NUM> and generate the longitudinal waves and/or shear waves in the object <NUM> and/or the plate waves and/or shear waves on the surface <NUM> of the object <NUM> (e.g., ultrasonic vibrations in the object <NUM>) to atomize the cleaning medium <NUM> and debris <NUM> (e.g., debris particles retained by the cleaning medium <NUM>). The vacuum <NUM> may vacuum the atomized cleaning medium <NUM> and debris <NUM>.

Optionally, a plurality of air coupled ultrasonic devices <NUM> (e.g., the ultrasonic devices shown and described in <FIG>) may be located in relatively close proximity to the surface <NUM> of the object <NUM>. For example, the ultrasonic devices <NUM> may be positioned generally opposite the location of the cleaning head <NUM> and the ultrasonic devices <NUM> (e.g., an opposing surface <NUM>). The ultrasonic devices <NUM> may be connected to one or more ultrasonic device holding fixtures <NUM>. The ultrasonic holding fixtures <NUM> may provide for manual or electromechanical movement and positioning of the ultrasonic devices <NUM> relative to the object <NUM>, such that the ultrasonic devices <NUM> may move along with the cleaning head <NUM>.

Thus, the disclosed system <NUM> may be utilized in a variety of different configurations dependent upon a given cleaning operation and type of object <NUM> being cleaned. For example, the object <NUM> and all of the ultrasonic devices (e.g., ultrasonic devices <NUM> and <NUM>) may be stationary and the cleaning head <NUM> (e.g., including the cleaning medium dispenser <NUM> and the vacuum <NUM>) may move in one or more directions (e.g., alongside the object <NUM> in the X and/or Y directions).

As another example, the object <NUM> and particular ultrasonic devices (e.g., ultrasonic devices <NUM> and <NUM>) may be stationary and the cleaning head <NUM> (e.g., including the ultrasonic devices <NUM>, the cleaning medium dispenser <NUM> and the vacuum <NUM>) and certain ultrasonic devices (e.g., ultrasonic devices <NUM>) may move in one or more directions (e.g., alongside the object <NUM> in the X and/or Y directions).

As another example, the object <NUM> may be stationary and the cleaning head <NUM> (e.g., including the ultrasonic devices <NUM>, the cleaning medium dispenser <NUM> and the vacuum <NUM>) and all of the ultrasonic devices (e.g., ultrasonic devices <NUM> and <NUM>) may move in one or more directions (e.g., alongside the object <NUM> in the X and/or Y directions).

As another example, the object <NUM>, the cleaning head <NUM> (e.g., including the ultrasonic devices <NUM>, the cleaning medium dispenser <NUM> and the vacuum <NUM>) and all of the ultrasonic devices (e.g., ultrasonic devices <NUM> and <NUM>) may move one or more directions. As yet another example, the cleaning head <NUM> (e.g., including the ultrasonic devices <NUM>, the cleaning medium dispenser <NUM> and the vacuum <NUM>) and all of the ultrasonic devices (e.g., ultrasonic devices <NUM> and <NUM>) may be stationary and the object <NUM> may move in one or more directions (e.g., alongside the cleaning head <NUM> and/or the ultrasonic devices in the X and/or Y directions).

The size, quantity, location, relative position, orientation angle, and distance from the surface <NUM> of the object <NUM> (e.g., the cleaning zone <NUM>) may be considered when sizing and configuring the ultrasonic devices <NUM>, <NUM> and <NUM> for a given cleaning operation. For example, a relatively small number of ultrasonic devices having high power may be used. As another example, a relatively large number of ultrasonic devices having low power may be used.

Referring to <FIG>, one aspect of the disclosed method, generally designated <NUM>, for surface cleaning of an object may begin at block <NUM> by providing an object having at least one surface to be cleaned.

As shown at block <NUM>, a cleaning medium (e.g., steam or hot water) may be delivered to the surface of the object. For example, the cleaning medium may be discharged from a cleaning medium dispenser. The cleaning medium may dislodge contaminants and debris disposed on the surface of the object.

As shown at block <NUM>, ultrasonic waves may be delivered to the surface of the object. The ultrasonic waves may generate ultrasonic vibrations (e.g., in response to longitudinal waves, shear waves, surface waves and/or plate waves) on the surface of the object. The ultrasonic waves may be emitted by one or more ultrasonic devices. The ultrasonic devices may be air coupled to the object.

As shown at block <NUM>, optionally, the object may be mounted to a holding fixture prior to the step of delivering the cleaning medium or delivering the ultrasonic waves to the surface of the object. The holding fixture may define an acoustically resonate system.

As shown at block <NUM>, ultrasonic waves may be delivered to the holding fixture to generate ultrasonic vibrations in the object. The ultrasonic waves may be emitted by one or more ultrasonic devices. The ultrasonic devices may be air coupled to the holding fixture or physically coupled to the holding fixture.

As shown at block <NUM>, the ultrasonic waves may be focused on a cleaning zone on the surface of the object. As shown at block <NUM>, the focused waves may generate a pattern of ultrasonic vibrations on the surface of the object and/or in the object.

As shown at block <NUM>, the pattern of ultrasonic vibrations may define an ultrasonic interaction volume around at least a portion of the surface of the object through interference of the ultrasonic waves.

As shown at block <NUM>, atomizing the cleaning medium and any contaminants and debris collected within the cleaning medium in response to the ultrasonic vibrations on the surface of the object and/or in the object.

As shown at block <NUM>, a vacuum airflow may be applied to the surface of the object to collect atomized cleaning medium and any contaminant and debris (e.g., particles of contaminants and debris) captured by the cleaning medium.

Accordingly, the disclosed system and method may be used to clean one or more surfaces of a large and/or complex object by combining ultrasonic vibrations (e.g., via focused ultrasonic waves), a cleaning medium (e.g., steam) and a vacuum airflow. A plurality of ultrasonic devices (e.g., an array of ultrasonic devices) may generate and emit directional ultrasonic waves (e.g., ultrasonic beams) that are electronically and mechanically focused on particular areas (e.g., a cleaning zone) on the surface of the object. Activating and tuning the ultrasonic devices by various electronic and mechanical means may create desired patterns of ultrasonic vibrations in and on the object to achieve the cleaning effect. As an example, positioning and focusing of the ultrasonic waves may be achieved through movement of various cleaning heads and/or holding fixtures equipped with the ultrasonic devices. Tuning of the ultrasonic devices may be achieved with the concept of parametric array.

Referring generally to <FIG>, <FIG> and <FIG>, the various aspects of the disclosed system <NUM> for cleaning an object including a surface may include a cleaning medium dispenser <NUM> configured to deliver a cleaning medium <NUM> to the surface <NUM> of the object <NUM>, wherein the cleaning medium <NUM> may dislodge and capture debris <NUM> from the surface, an ultrasonic device <NUM> configured to deliver ultrasonic waves to the object <NUM>, wherein the ultrasonic waves <NUM> atomize the cleaning medium <NUM> and captured debris <NUM> from the surface, and a vacuum configured to provide a vacuum airflow, wherein the vacuum airflow collects atomized cleaning medium and captured debris.

In one aspect, the ultrasonic waves <NUM> may generate ultrasonic vibrations on the surface <NUM> of the object <NUM>. The ultrasonic waves <NUM> may generate ultrasonic vibrations in the object <NUM>. The ultrasonic waves <NUM> may include at least one of longitudinal waves, shear waves, surface waves and plate waves. The ultrasonic waves <NUM> may be focused to a cleaning zone <NUM> on the surface <NUM> of the object <NUM>.

In another aspect, the position of the cleaning medium dispenser <NUM>, the ultrasonic device <NUM> and the vacuum <NUM> may be adjustable with respect to the surface <NUM> of the object <NUM>. The cleaning medium dispenser <NUM>, the ultrasonic device <NUM> and the vacuum may be mounted to a cleaning head <NUM>. The cleaning head <NUM> may be mounted to a movable assembly <NUM>, wherein the movable assembly <NUM> may position the cleaning head <NUM> relative to the surface <NUM>.

In another aspect, the disclosed system <NUM> may include a holding fixture <NUM> configured to hold the object <NUM>, wherein the holding fixture <NUM> defines an acoustically resonating system, and wherein the ultrasonic waves <NUM> generate ultrasonic vibrations in the object <NUM>. The ultrasonic device <NUM> may be coupled to the holding fixture and the cleaning medium dispenser <NUM> and the vacuum <NUM> may be mounted to the cleaning head <NUM>. The ultrasonic device <NUM> may be coupled to the holding fixture <NUM> and a position of the cleaning medium dispenser <NUM> and the vacuum <NUM> may be adjustable with respect to the object <NUM>. The ultrasonic device <NUM> may be physically coupled to the holding fixture <NUM>. The ultrasonic device <NUM> may be air coupled to at least one of the holding fixture <NUM> and the object <NUM>.

In another aspect, the cleaning medium dispenser <NUM>, the ultrasonic device <NUM> and the vacuum <NUM> may be mounted to the cleaning head <NUM>. The holding fixture <NUM> may include a second ultrasonic device <NUM> configured to deliver second ultrasonic waves <NUM> through the holding fixture <NUM> and into the object <NUM>. The ultrasonic waves <NUM> and the second ultrasonic waves <NUM> may generate ultrasonic vibrations in the object <NUM> to atomize the cleaning medium <NUM> from the surface <NUM>. The holding fixture <NUM> may be a part of the object <NUM>.

In another aspect, the disclosed system <NUM> may include a second ultrasonic device <NUM>, <NUM> configured to deliver second ultrasonic waves <NUM>, <NUM> to the object <NUM>. The ultrasonic device <NUM> may be air coupled to the object <NUM>. The second ultrasonic device <NUM> may be air coupled to the object <NUM>. Interference of the ultrasonic waves <NUM> and the second ultrasonic waves <NUM> may define an ultrasonic interaction volume <NUM> around at least a portion of the surface <NUM>.

In one aspect, the holding fixture <NUM> may be configured to hold the object <NUM>. The holding fixture <NUM> may an acoustically resonating system. The ultrasonic waves <NUM> and the second ultrasonic waves <NUM> may generate ultrasonic vibrations in the object <NUM> to atomize the cleaning medium <NUM> from the surface <NUM>. The second ultrasonic device <NUM> may be physically coupled to the holding fixture <NUM>. The ultrasonic device <NUM> may be air coupled to at least one of the object <NUM> and the holding fixture <NUM>.

In another aspect, the disclosed system <NUM> may include a plurality of ultrasonic devices <NUM>, <NUM>, <NUM> arranged in an acoustic array. The plurality of ultrasonic devices <NUM>, <NUM>, <NUM> may deliver ultrasonic waves <NUM>, <NUM>, <NUM> to the object <NUM>. The ultrasonic waves <NUM>, <NUM>, <NUM> may generate a pattern of ultrasonic vibrations in the object <NUM>. The acoustic array may include at least one of a parametric array and a phased array. The plurality of ultrasonic devices <NUM>, <NUM> may be air coupled to the object <NUM>.

In another aspect, the holding fixture <NUM> may be configured to hold the object <NUM>. The holding fixture <NUM> may define an acoustically resonating system. At least a portion of a plurality of ultrasonic devices <NUM> may be physically coupled to the holding fixture <NUM>. At least a portion of a plurality of ultrasonic devices <NUM>, <NUM> may be air coupled to at least one of the holding fixture <NUM> and the object <NUM>.

In another aspect, the cleaning medium <NUM> may disintegrate and dislodge the debris <NUM> from the surface. The ultrasonic waves may reduce adhesion between the surface <NUM> and the debris <NUM>. The cleaning medium <NUM> may include a fluid. The fluid may include at least one of a liquid and a gas. The cleaning medium <NUM> may include at least one of steam, water, and an aqueous solution.

Referring generally to <FIG>, <FIG>, <FIG> and <FIG>, one aspect of the disclosed method <NUM> for cleaning an object including a surface may include the steps of: (<NUM>) delivering the cleaning medium <NUM> to the surface <NUM> of the object <NUM>, (<NUM>) delivering ultrasonic waves <NUM>, <NUM>, <NUM> to the object <NUM> to atomize the cleaning medium <NUM>, and (<NUM>) applying a vacuum airflow <NUM> to collect atomized cleaning medium <NUM>. The ultrasonic waves <NUM>, <NUM>, <NUM> may generate ultrasonic vibrations in the object <NUM>.

In another aspect, the disclosed method <NUM> may include the steps of: (<NUM>) mounting the object <NUM> to the holding fixture <NUM>, wherein the holding fixture <NUM> may define an acoustically resonating system, and (<NUM>) delivering the ultrasonic waves <NUM>, <NUM>, <NUM> to at least one of the holding fixture <NUM> and the object <NUM> to generate ultrasonic vibrations in the object <NUM>.

In another aspect, the disclosed method <NUM> may include the steps of: (<NUM>) focusing the ultrasonic waves <NUM>, <NUM>, <NUM> on the cleaning zone <NUM> on the surface <NUM> of the object <NUM>, and (<NUM>) generating a pattern of ultrasonic vibrations in the object <NUM>. The step of generating the pattern of ultrasonic vibrations may include defining an ultrasonic interaction volume <NUM> around at least a portion of the surface <NUM> through interference of the ultrasonic waves <NUM>, <NUM>, <NUM>.

In another aspect, the cleaning medium <NUM> may disintegrate and dislodge debris <NUM> from the surface <NUM>. The cleaning medium <NUM> may include at least one of a liquid and a gas. The ultrasonic waves <NUM>, <NUM>, <NUM> may reduce adhesion between the surface <NUM> and the debris <NUM>.

Examples of the disclosure may be described in the context of an aircraft manufacturing and service method <NUM>, as shown in <FIG>, and an aircraft <NUM>, as shown in <FIG>. During pre-production, the aircraft manufacturing and service method <NUM> may include specification and design <NUM> of the aircraft <NUM> and material procurement <NUM>. During production, component/subassembly manufacturing <NUM> and system integration <NUM> of the aircraft <NUM> takes place. Thereafter, the aircraft <NUM> may go through certification and delivery <NUM> in order to be placed in service <NUM>. While in service by a customer, the aircraft <NUM> is scheduled for routine maintenance and service <NUM>, which may also include modification, reconfiguration, refurbishment and the like.

For the purposes of this description, a system integrator may include without limitation any number of aircraft manufacturers and major-system subcontractors; a third party may include without limitation any number of venders, subcontractors, and suppliers; and an operator may be an airline, leasing company, military entity, service organization, and so on.

As shown in <FIG>, the aircraft <NUM> produced by example method <NUM> may include an airframe <NUM> with a plurality of systems <NUM> and an interior <NUM>. Examples of the plurality of systems <NUM> may include one or more of a propulsion system <NUM>, an electrical system <NUM>, a hydraulic system <NUM>, and an environmental system <NUM>. Any number of other systems may be included. Although an aerospace example is shown, the principles of the disclosed system <NUM> and method <NUM> may be applied to other industries, such as the automotive industry.

Apparatus and methods embodied herein may be employed during any one or more of the stages of the production and service method <NUM>. For example, components or subassemblies corresponding to component/subassembly manufacturing <NUM>, system integration <NUM>, and or maintenance and service <NUM> may be fabricated or manufactured using the disclosed system <NUM> (<FIG>, <FIG> and <FIG>) and method <NUM> (<FIG>). Also, one or more apparatus examples, method examples, or a combination thereof may be utilized during component/subassembly manufacturing <NUM> and/or system integration <NUM>, for example, by substantially expediting assembly of or reducing the cost of an aircraft <NUM>, such as the airframe <NUM> and/or the interior <NUM>. Similarly, one or more of apparatus examples, method examples, or a combination thereof may be utilized while the aircraft <NUM> is in service, for example and without limitation, to maintenance and service <NUM>.

Claim 1:
A system (<NUM>) for cleaning an object comprising a surface, said system comprising:
a steam source comprising a water tank and a heating mechanism (<NUM>) to generate steam;
a cleaning head (<NUM>) including a vacuum chamber (<NUM>) having an open end (<NUM>);
a cleaning medium dispenser (<NUM>) comprising a nozzle (<NUM>) configured to deliver said steam (<NUM>) to said surface (<NUM>), wherein said steam (<NUM>) dislodges and captures debris (<NUM>) from said surface (<NUM>);
a plurality of ultrasonic devices (<NUM>) configured to deliver ultrasonic waves (<NUM>) to said object, wherein said ultrasonic waves (<NUM>) atomize said steam (<NUM>) and captured debris from said surface (<NUM>);
wherein at least one of the plurality of ultrasonic devices (20a, 20b, 20c) is located within the vacuum chamber, and at least one of the plurality of ultrasonic devices (20d, 20e) is located outside of the vacuum chamber;
and
a vacuum (<NUM>) configured to provide a vacuum airflow (<NUM>) within the vacuum chamber (<NUM>), wherein said vacuum airflow (<NUM>) collects atomized steam (<NUM>) and captured debris.