System and method for surface cleaning

A system for cleaning an object may include a cleaning medium dispenser configured to deliver a cleaning medium to a surface of the object, wherein the cleaning medium dislodges and captures debris from the surface, an ultrasonic device configured to deliver ultrasonic waves to the object, wherein the ultrasonic waves generate ultrasonic vibrations in the object to atomize the cleaning medium from the surface and a vacuum configured to provide a vacuum airflow, wherein the vacuum airflow collects atomized cleaning medium and debris from the surface.

FIELD

The present disclosure is generally related to surface cleaning systems and, more particularly, to systems and methods employing a cleaning medium, ultrasonic waves and a means to remove debris from a surface of an object, such as employing vacuum suction and airflow.

BACKGROUND

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.

SUMMARY

In one aspect, the disclosed system for cleaning an object may include a cleaning medium dispenser configured to deliver a cleaning medium to the surface, wherein the cleaning medium dislodges and captures debris from the surface, an ultrasonic device configured to deliver ultrasonic waves to the object, wherein the ultrasonic waves atomize the cleaning medium and captured debris from the surface, and a vacuum configured to provide a vacuum airflow, wherein the vacuum airflow collects atomized cleaning medium and captured debris.

In another aspect, disclosed is a method for cleaning an object, the method may include the steps of: (1) delivering a cleaning medium to the surface, (2) delivering ultrasonic waves to the object to atomize the cleaning medium, and (3) applying a vacuum airflow to collect atomized cleaning medium.

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

DETAILED DESCRIPTION

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 toFIG. 1, one aspect of the disclosed system, generally designated10, for surface cleaning of an object may include a cleaning assembly12utilized for cleaning one or more surfaces16of one or more objects18, such as during fabrication, assembly and/or maintenance of the object18. For example, the object18may include any manufactured part, component, assembly or sub-assembly having a large and/or complex surface16, including, but not limited to, complex three-dimensional objects18and/or large two-dimensional objects18, such as an aircraft component (e.g., an airplane wing).

The cleaning assembly12may include at least one ultrasonic device20, at least one cleaning medium dispenser22and at least one vacuum24. The cleaning medium dispenser22may deliver a cleaning medium26to the surface16of the object18. The ultrasonic device20may deliver ultrasonic waves28to the object18to generate ultrasonic vibrations within (e.g., throughout at least a portion of) the object18and/or on the surface16of the object to atomize the cleaning medium26. The vacuum24may remove the atomized cleaning medium26along with any debris30collected by the cleaning medium26from the surface16of the object18.

As used herein, debris30may include any contaminant, substance and/or other unwanted constituent material disposed on the surface16of the object18. Debris30may include any solid, semi-solid, liquid and/or semi-liquid material of any type, without limitation.

The ultrasonic device20, the cleaning medium dispenser22and the vacuum24may be mounted to a cleaning head32. The cleaning head32may deliver cleaning medium26(e.g., from the cleaning medium dispenser22), ultrasonic waves28(e.g., from the ultrasonic device20) and vacuum airflow50(e.g., from the vacuum24) directly to a cleaning zone54on the surface16of the object18.

An ultrasonic generator40may be coupled to the cleaning head32. The ultrasonic generator40(e.g., an ultrasonic power amplifier and function generator) may supply energy to the ultrasonic device20. The ultrasonic supply line42(e.g., a flexible acoustic waveguide) may couple the ultrasonic generator40to the cleaning head32such that ultrasonic waves28may be applied from the ultrasonic devices20to the surface16of the object18(e.g., about the cleaning zone54).

The cleaning medium source44may be fluidly coupled to the cleaning head32. The cleaning medium source44may supply the cleaning medium26to the cleaning medium dispenser22. The cleaning medium supply line46may fluidly couple the cleaning medium source44to the cleaning head32such that cleaning medium26may be provided from the cleaning medium dispenser22within the vacuum chamber98(FIG. 4) and/or to the surface16of the object18(e.g., about the cleaning zone54).

The vacuum source48may be fluidly coupled to the cleaning head32. The vacuum source48may supply a vacuum airflow50(e.g., vacuum suction) to the vacuum24. The vacuum supply line52may fluidly couple the vacuum source48to the cleaning head32such that vacuum suctioning (e.g., vacuum airflow50) may be applied from the vacuum24within the vacuum chamber98and/or to the surface16of the object18(e.g., about the cleaning zone54).

The disclosed system10may be incorporated into a movable assembly112. The object18(e.g., one or more surfaces16of the object18) may be cleaned with the cleaning head32, which may be moved alongside the object18by the movable assembly112. A position (e.g., location) of the cleaning head32with respect to the object18(e.g., the surface16of the object18) and a desired distance between the cleaning head32and the object18may be set and/or maintained by the movable assembly112.

The cleaning medium26may include any suitable substance and/or material that are able to perform the cleaning action in combination with the ultrasonic waves28and vacuum airflow50. The cleaning medium26may include any cleaning fluid. The cleaning fluid may include a liquid or a gas. As an example, the cleaning medium26may include liquid water (e.g., hot water and/or cold water). As another example, the cleaning medium26may include any aqueous solutions (e.g., organic solvents, surfactants, detergents or other chemicals). As another example, the cleaning medium26may be steam (e.g., vaporized water). As another example, the cleaning medium26may be air (e.g., forced and/or pressurized air). As another example, the cleaning medium26may 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 medium26may include any combination of cleaning fluids and/or blasting media.

Thus, the removal of debris30may be achieved by the combination of the cleaning medium26, the ultrasonic waves28and the vacuum airflow50and, therefore, may be completely non-contact. For example, the cleaning medium dispenser22, the ultrasonic devices20and the vacuum24may be positioned at a distance (e.g., spaced away) from the object18to be cleaned and do not impose any risk of contamination of the surface16of the object18.

In an example implementation, during a cleaning operation, the cleaning medium26may form droplets and/or thin films on the surface16of the object18. The debris30may be captured, suspended and/or dissolved in the cleaning medium26. Ultrasonic waves28delivered to the surface16by the ultrasonic devices20may facilitate atomization and/or evaporation of the droplets and/or films and, thus, removal of the debris30from the surface16by the vacuum24.

In a particular, non-limiting example, the disclosed system10may 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 medium26may include wet steam jets (e.g., having at least 5%-6% water) and may form droplets (e.g., water droplets) and/or thin liquid films (e.g., thin films of water) on the surface16of the object18. Optionally, the cleaning medium26may include the addition of cleaning solutions. The debris30may be dissolved and/or suspended in the cleaning medium26(e.g., particles of debris30captured within a liquid envelope). Ultrasonic waves28delivered to the surface16by the ultrasonic devices20may facilitate atomization and/or evaporation of the droplets and/or films and, thus, removal of the debris30from the surface16by the vacuum24.

During a dry cleaning operation, the cleaning medium26may include dry steam jets (e.g., having less than 5%-6% water) and may disintegrate the debris30on the surface16of the object18. Ultrasonic waves28delivered to the surface16by the ultrasonic devices20may reduce adhesion of the debris30to the surface16and, thus, facilitate removal of the debris30from the surface16by the vacuum24. Referring toFIG. 2, in one implementation, the movable assembly112may be a robotic assembly34. The robotic assembly34may provide for automated or semi-automated cleaning of one or more objects18. For example, the cleaning head32(e.g., including at least one ultrasonic device20, at least one cleaning medium dispenser22and at least one vacuum24) may be mounted to an end adaptor36of a robotic arm38of the robotic assembly34. The end adaptor36may be mounted to a movable joint110located on an end of the robotic arm38of the robotic assembly34. The movable joint110may facilitate positioning of the cleaning head32in a desired position and orientation approximating the surface16of the object18being cleaned. For example, the movable joint110may include a rotary joint for positioning the cleaning head32(e.g., positioning of the end adaptor36) during cleaning of the surface16and/or articles protruding from the surface16(e.g., fasteners) of the object18.

A supply line82may extend from the cleaning head32to a cleaning source84that may, for example, be mounted to a base85of the robotic assembly34. The supply line82may include an ultrasonic supply line42, a cleaning medium supply line46and a vacuum supply line52. Similarly, the cleaning source84may include an ultrasonic generator40, a cleaning medium source44and a vacuum source48.

Additionally, a fluid injection unit86, a cleaning filter88and a contamination-accumulating container90(e.g., a waste receptacle) may be included in the movable assembly112(e.g., in the base85of the robotic assembly34). The fluid injection unit86may inject a cleaning solution124into the cleaning medium supply line46or to the surface16of the object18. The contamination-accumulating container90may be coupled to the vacuum supply line52for receiving cleaning medium26and debris30(e.g., water vapor, detergent, chemicals, or other materials) that may be suctioned from the surface16of the object18.

Referring toFIG. 3, in another implementation, the robotic assembly34may include one or more manufacturing devices92mounted, for example, on the end adaptor36. The manufacturing device92may include a device for performing operations on the object18(FIG. 1). For example, the manufacturing device92may include one or more devices for machining, drilling, painting, sealing, imaging, testing, inspecting, sensing, and other operations on the object18(e.g., during fabrication, assembly and/or maintenance). The manufacturing device92may be coupled via a supply line94to a power supply/material supply unit96, for example, at the base85of the robotic assembly34for delivery of materials and/or power to the manufacturing device92.

The supply line94may deliver lubricant, sealant, coating material, or other materials to the manufacturing device92. The supply line94may also deliver electrical power, pressurized air, hydraulic fluid, and other mediums for operating the manufacturing device92. The cleaning head32may be employed in the robotic assembly34to perform a cleaning operation on the object18prior to or following the performance of one or more manufacturing, inspection, repair, or maintenance operations on the object18by one or more of the manufacturing devices92.

Referring toFIG. 4, in one implementation, the cleaning head32may include a vacuum chamber98having an open end100. For example, a plurality of sidewalls102may define a partially enclosed vacuum chamber98having a rectangular cross-sectional shape. As another example, a continuous sidewall102may define a partially enclosed vacuum chamber98having an annular cross-sectional shape. The vacuum chamber98may be sized and configured according to a given cleaning operation and/or application, such as the size of the object18, the shape of the object18and/or the complexity of the object18. Similarly, the size of the cleaning zone54may be determined by area covered by the cleaning medium26, the vacuum airflow50and ultrasonic waves28(e.g., waves28aand28b).

In an example construction, the cleaning head32may be removably attached to (e.g., detachable from) the movable assembly112(e.g., the end adaptor36of the robotic arm38). In order to facilitate detachment of the cleaning head32and replacement of a cleaning head32having the same or a different configuration, the cleaning head32may 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 head32to the supply line82and/or the movable assembly112(e.g., the end adaptor36). The detachable arrangement of the cleaning head32may facilitate mounting of any one of a variety of different cleaning heads32having different sizes, shapes, and configurations (e.g., quantity and/or configurations of ultrasonic devices20, cleaning medium dispensers22and/or vacuums24) to correspond to a given cleaning application.

The cleaning head32may include a plurality of ultrasonic devices20(identified individually as20a,20b,20c,20dand20e). Each ultrasonic device20may 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 device20may 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 waves28). The plurality of ultrasonic devices20may be configured into an array of ultrasonic devices20. The array of ultrasonic devices20may include a geometry that directs and concentrates the ultrasonic waves28onto particular areas (e.g., cleaning zones54) on the surface16of the object18to be cleaned.

The high frequency ultrasonic vibrations generated by the ultrasonic waves28may atomize or aerosolize the droplets and/or thin films of cleaning medium26that are formed on the surface16of the object18. The vacuum24may then collect the atomized cleaning medium26and debris30(e.g., particles of debris30) within the vacuum airflow50, which may be deposited in the contamination-accumulating container90.

In addition, the ultrasonic waves28(e.g., focused energy) may promote and/or facilitate evaporation of the cleaning medium26from the surface16of the object18(e.g., about the cleaning zone54). This evaporation may result from excitation (e.g., at the molecular level) of the cleaning medium26on the surface16of the object18. This excitation may cause friction and thus turns the acoustic energy from the ultrasonic waves28into heat. This heat may cause the water molecules of the cleaning medium26to move apart forming gas.

The ultrasonic waves28may be modulated, such that the interaction of the modulated ultrasonic waves28with the object18and air medium (e.g., air between the ultrasonic devices20and the surface16of the object18) generates desired patterns of ultrasonic vibrations. For example, the ultrasonic devices20may generate ultrasonic waves28having different frequencies and/or amplitudes such that when the ultrasonic waves28impinge on the object18, desired patterns of ultrasonic vibrations may be generated on the surface16of the object18and in the air medium.

The initial patterns generated by the ultrasonic waves28may be complex but eventually, after many reflections and as the ultrasonic waves28travel 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 medium26and debris30may 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 surface16of the object18at desired locations (e.g., the cleaning zone54) by placing, activating and tuning the ultrasonic devices20to form an acoustically resonating system. The acoustically resonating system may deliver the desired patterns of ultrasonic vibrations to the entire object18, which, for example, may be fixed with a holding fixture56(FIG. 6). The air coupled ultrasonic devices20, which are located outside the object18, may create the desired patterns of ultrasonic vibrations directed about the cleaning zone54. Focusing ultrasonic stresses may be achieved electronically (e.g., tuning the ultrasonic devices20) and/or mechanically (e.g., positioning the ultrasonic devices20). Air-coupled, parametric acoustic arrays (e.g., parametric arrays or phased arrays) of ultrasonic devices20may be specifically configured to impinge ultrasonic vibrations on complex three-dimensional objects to facilitate atomization of the droplets and thin films of cleaning medium26containing the debris30.

As used herein, a parametric array may include a plurality of ultrasonic devices20(e.g., piezoelectric transducers) configured to produce a narrow primary beam of sound (e.g., ultrasonic waves28). 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., ω1 and ω2) at high enough amplitudes to produce a difference frequency (e.g., ω2-ω1).

As used herein, a phased array may include a plurality of ultrasonic devices20(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 devices20may 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 devices20may be pulsed simultaneously or independently of each other in varying patterns to achieve specific beam characteristics.

As illustrated inFIG. 4, ultrasonic device20a,20band20cmay be located within the vacuum chamber98. For example, ultrasonic device20amay be positioned at a generally central location within the vacuum chamber98and ultrasonic devices20band20cmay be positioned proximate (e.g., at or near) edges of the vacuum chamber98(e.g., proximate the open end100.) Ultrasonic devices20dand20emay be located outside of the vacuum chamber98. For example, ultrasonic devices20dand20emay be attached to one or more holding fixtures114. The holding fixture114may be attached (e.g., removably attached) to the cleaning head32and/or end effector36. Ultrasonic devices20dand20emay be positioned at a fixed location on an associated holding fixture114or may be movable (e.g., manually or electromechanically) relative to the associated holding fixture114.

For example, the plurality of ultrasonic devices20(e.g., the array of ultrasonic devices20) 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 zones54) that may be moved around the object18as position, frequency and/or wave mode are changed. The cleaning zone54may be moved, through user selection, allowing cleaning at specific points on the surface16of the object18.

Specific ultrasonic mode and frequency excitation over a frequency range (e.g., from 1 Hz to 500 MHz) may be provided, wherein frequency tuning over a selected frequency range may be achieved by optimally positioning the ultrasonic devices20and/or by modal vibration combinations. How the ultrasonic stresses are focused for effective atomization and/or evaporation of the cleaning medium26and debris30from the surface16of the object18may depend on the particular cleaning operation. For example, the type of debris30, the thickness of the debris30, the structural geometry of the object18, environmental conditions and the like may affect the configuration of the ultrasonic devices20.

As an example, the frequency of one or more of the ultrasonic devices20may be tuned to a particular frequency or frequency range depending upon the particle size of the debris30. As an example, relatively low frequencies (e.g., below approximately 20 kHz) may atomize the cleaning medium26into a relatively large mist (e.g., approximately 10 microns and above). Thus, the mist of atomized cleaning medium26may capture relatively large particles of debris30(e.g., approximately 10 microns and above). As another example, relatively high frequencies (e.g., above approximately 1 MHz) may atomize the cleaning medium26into a relatively small mist (e.g., approximately 3 microns and below). Thus, the mist of atomized cleaning medium26may capture relatively small particles of debris30(e.g., approximately 3 microns and below).

As another example, the frequency of one or more of the ultrasonic devices20may be tuned to a particular frequency or frequency range depending upon the size and/or shape of the surface16to be cleaned. As an example, large and/or generally flat surfaces may have relatively large particles of debris30(e.g., approximately 10 microns and above). Thus, relatively low frequencies (e.g., below approximately 20 kHz) may be used to atomize the cleaning medium26and the debris30from the surface16. As another example, small and/or complex surfaces may have relatively small particles of debris30(e.g., approximately 3 microns and below). Thus, relatively high frequencies (e.g., above approximately 1 MHz) may be used to atomize the cleaning medium26and the debris30from the surface16.

The ultrasonic devices20may be configured to generate a variety of different types of ultrasonic waves28(FIG. 1) applied to the surface16of the object18, including, but not limited to, longitudinal waves, shear waves, surface waves and/or plate waves. For example, ultrasonic device20amay generate ultrasonic waves28a(e.g., longitudinal and/or shear waves) in the object18and ultrasonic devices20b,20c,20dand20emay generate ultrasonic waves28b(e.g., surface and/or plate waves) on the surface16of the object18. As another example, ultrasonic devices20a,20band20cmay generate ultrasonic waves28a(e.g., longitudinal waves and/or shear waves) in the object18and ultrasonic devices20dand20emay generate ultrasonic waves28b(e.g., surface waves and/or plate waves) on the surface16of the object18. Those skilled in the art will appreciate that any individual ultrasonic device20and/or combination of ultrasonic devices20(e.g., arrays of ultrasonic devices20) may be configured to generate any combination of ultrasonic waves28(e.g., longitudinal waves and/or shear waves in the object18and/or surface waves and/or plate waves on the surface16of the object18).

Additionally, the ultrasonic devices20may also be used for non-destructive inspection of the object18and/or structural health monitoring of the object18. For example, at least two ultrasonic devices20(e.g., transmitter and receiver) may be positioned above the surface16of the object18. The positions of the devices20may be adjusted relative to each other and relative to and along the surface16in order to define the directions of sonic propagation at appropriate angles to generate and detect surface and/or plate waves on the surface16. The generation and detection of the ultrasonic waves28may depend on several factors including, but not limited to, the elastic properties of the material of the surface16and the presence of contamination (e.g., debris30) and water. A reference library of various patterns of the ultrasonic waves28generated and detected by the ultrasonic devices20on the reference surfaces may be built and used in non-destructive inspection of the conditions (e.g., cleanliness) of the monitored surface16of the object18.

The cleaning medium dispenser22may be located within the vacuum chamber98at an orientation sufficient to deliver the cleaning medium26to the surface16of the object18. The cleaning medium dispenser22may include a nozzle104fluidly coupled to the cleaning medium supply line46. The nozzle104may include a nozzle outlet106configured to discharge the cleaning medium26directly into the vacuum chamber98and/or on the surface16of the object18(e.g., within the cleaning zone54). The cleaning medium26(e.g., a water spray or steam cloud) may facilitate the removal of debris30(FIG. 1) from one or more surfaces16of the object18.

The cleaning medium dispenser22(e.g., the nozzle104) may be configured to discharge cleaning medium26in a manner such that one or more surfaces16of the object18may be exposed to the cleaning medium26for dislodging and removing debris30from the surface16of the object18. For example, the nozzle outlet106may be configured to discharge cleaning medium26along a generally axial direction toward one or more surfaces16of the object18at the open end100of the cleaning head32. However, the nozzle outlet106may be configured to discharge cleaning medium26in any one of a variety of directions and/or angles.

Although a single nozzle104with a single nozzle outlet106is shown, any number of nozzles104and/or nozzle outlets106in any size and location may be provided. For example, a plurality of nozzles104and/or a plurality of nozzle outlets106may extend into the vacuum chamber98at different locations to provide a more uniform distribution of cleaning medium26. Further, although the nozzle104is illustrated as being fluidly coupled to an end (e.g., opposite the open end100) of the vacuum chamber98, one or more nozzles104may be included to provide cleaning medium26from one or more locations along the sidewalls102of the vacuum chamber98(e.g., proximate the open end100).

In an example implementation, the cleaning medium26may be water (e.g., hot water), the cleaning medium dispenser22may include a nozzle104suitable to discharge water (e.g., in the form of a drip, a stream, a spray or a mist), the cleaning medium supply line46may be a water supply line, and the cleaning medium source44may be a water source (e.g., water tank). Optionally, the cleaning medium source44may include a heating mechanism120(FIG. 1) to heat the water to a desired cleaning temperature.

In another example implementation, the cleaning medium26may be steam (e.g., wet steam and/or dry steam), the cleaning medium dispenser22may include a nozzle104suitable to discharge steam (e.g., in the form a spray, a mist, or a jet), the cleaning medium supply line46may be a steam supply line and the cleaning medium source44may be a steam source (e.g., water tank and a heating mechanism120(FIG. 1) to generate steam). For example, the cleaning head32may be configured such that a steam jet is discharged from the nozzle outlet106resulting in the formation of a steam cloud within the vacuum chamber98and/or on the surface16of the object18.

The cleaning medium26(e.g., steam, hot water, and/or an aqueous cleaning solution) may facilitate the removal of debris30(FIG. 1) from one or more surfaces16of the object18. For example, the steam cloud may promote the dislodgement of debris30(FIG. 1) from the surface16of the object18by releasing and breaking up bonds between the debris30and the surface16of the object18. The breaking up of the debris30may result from a plurality of micro-condensations that may occur when relatively tiny hot water vapor molecules contact the relatively cooler debris30. The micro-condensations may provide energy to break the bonds within the debris30and bonds between the debris30and the surface16of the object18. The result of the micro-condensations and the breaking of the bonds may be a plurality of relatively small particles of debris30that may become entrained in water suspension (e.g., within a liquid envelope) in the cleaning medium26(e.g., the steam cloud).

Additionally, steam may have a relatively low moisture content such as between approximately 2 percent and 10 percent moisture and, more preferably, between approximately 4 percent and 7 percent moisture which may enable the surface16of the object18to dry relatively quickly. Further, the low moisture content of steam may result in relatively low water usage during cleaning operations.

The flow of cleaning medium26into the vacuum chamber98and/or to the surface16of the object18may be provided by the cleaning medium supply line46. In an example construction, the cleaning medium supply line46may extend from the cleaning medium source44(e.g., at the base85of the robotic assembly34) (FIG. 2) to the cleaning head32. Thermal insulation may cover a substantial portion of the cleaning medium supply line46to preserve the temperature of the cleaning medium26(e.g., steam) within the cleaning medium supply line46and as a safety precaution for personnel using the system10. The flow of cleaning medium26from the cleaning medium supply line46into the cleaning medium dispenser22(e.g., the nozzle104) 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 line46and/or to the cleaning head32.

The temperature and/or the pressure of the cleaning medium26(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 medium26be controlled to provide cleaning medium26at a temperature that may avoid heat damage to the material composition of the object18and/or the surface16being cleaned. Similarly, the pressure of the cleaning medium26may be regulated (e.g., by means of the valve) such that cleaning medium26may be discharged from the nozzle outlet106in a manner that the velocity of the cleaning medium26is high enough to contact the surface16of the object18prior to atomization of the cleaning medium26(e.g., by the ultrasonic waves28) and vacuum suctioning of the cleaning medium26and any collected debris30into the vacuum24(FIG. 1). Control of cleaning medium26from the cleaning medium source44(FIG. 1) may be preprogrammed, for example, into the movable assembly112.

The vacuum24(FIG. 1) may be fluidly coupled to the vacuum supply line52(e.g., a vacuum hose) to provide vacuum suctioning (e.g., vacuum airflow50) within the vacuum chamber98and/or to the surface16of the object18. The corresponding vacuum airflow50may be directed to the vacuum source48(FIG. 1) through one or more vacuum inlet manifolds122. The vacuum inlet manifold122may be located inside the vacuum chamber98.

The size, quantity, location, relative position, orientation angle, and distance from the surface16of the object18may be considered when sizing and configuring the cleaning head32for a given cleaning operation. Similarly, the overall size, shape, and configuration of the cleaning head32and/or the vacuum chamber98may also be configured complementary to the size, shape and configuration of the object8to be cleaned by the cleaning head32.

Referring again toFIG. 1, in another implementation, the system10may also include the fluid injection unit86for injecting cleaning solution124into the cleaning medium supply line46for mixing with the cleaning medium26that is provided to the cleaning head32(e.g., to the cleaning medium dispenser22).

The cleaning solution124of the fluid injection unit86may be provided in a composition that may promote or expedite the cleaning of the object18. For example, the cleaning solution124may include detergent and/or chemicals for injection into the cleaning medium supply line46, which results in a mixture of molecules of detergent and/or chemicals in the cleaning medium26. The detergent and/or chemicals may include, but are not limited to, solvents for breaking up or dissolving certain type of debris30into smaller debris particles. The detergent and/or chemicals may surround the debris30once the debris particles are broken loose from the surface16of the object18. 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 surface16of the object18.

For example, the cleaning solution124may include a composition for enhancing the cleaning of certain types of debris30, such as water- and/or oil-based fluids (e.g., hydraulic fluids and greases). The cleaning solution124may be injected into the cleaning medium26in a predetermined amount (e.g., upon activation of a release valve). The mixture of detergent and chemical molecules in the cleaning medium26(e.g., the steam cloud or hot water) may penetrate the relatively cooler debris30on the surface16of the object18and may further facilitate dislodgment of the debris30. In this regard, the cleaning solution124may include any one of a variety of other compositions, without limitation, for expediting or enhancing the cleaning of certain types of debris30.

Alternatively, the cleaning solution124(e.g., detergent and/or chemicals) may be applied directly to the surface16of the object18.

Referring toFIG. 5, in another implementation of the cleaning head32, ultrasonic devices20(referred to individually as ultrasonic devices20fand20g) may be located only outside of the vacuum chamber98. For example, ultrasonic devices20fand20gmay be attached to one or more holding fixtures114. The holding fixture114may be attached (e.g., removably attached) to the end effector36. Ultrasonic devices20fand20gmay be positioned at a fixed location on an associated holding fixture114or may be movable (e.g., manually or electromechanically) relative to the associated holding fixture114. Ultrasonic devices20fand20gmay generate ultrasonic waves28(e.g., longitudinal waves and/or shear waves) in the object18.

The cleaning medium dispenser22may deliver cleaning medium26(e.g., steam) to the surface16of the object18to dislodge the debris30(FIG. 1). The ultrasonic waves28(e.g., longitudinal and/or shear waves) may atomize the cleaning medium26holding the debris30(e.g., particles of debris30), which may them be collected by the vacuum airflow50.

Referring toFIG. 6, in another aspect, the disclosed system may include a holding fixture56configured to hold and/or support the object18. For example, the holding fixture56may be a component assembly fixture used to hold the object18during 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 fixture56may be used to hold the object18only during a cleaning operation. As yet another example, the holding fixture64may be a part of the object18.

At least one ultrasonic device58may be coupled to the holding fixture56. The ultrasonic devices58may deliver ultrasonic waves62to the object18through the holding fixture56. At least one ultrasonic generator72may supply energy to the ultrasonic devices58. An ultrasonic supply line74may electrically couple the ultrasonic generator72to the ultrasonic devices58such that ultrasonic waves62may be applied through the entire object18.

Each ultrasonic device58may be an ultrasonic transducer that converts energy into ultrasound (e.g., sound waves). For example, the ultrasonic device58may be a piezoelectric transducer that converts electrical energy into sound.

During a cleaning operation, the cleaning head32may be positioned in close proximity to the surface16of the object18, for example by the robotic assembly34. The cleaning medium26may be delivered to the surface16of the object18(e.g., about the cleaning zone54) from the cleaning medium dispenser22to dislodge debris30on the surface16. The ultrasonic waves28generated by the ultrasonic devices20in the cleaning head32and delivered to the surface16of the object18may work in concert with the ultrasonic waves62generated by the ultrasonic devices58of the holding fixture56and delivered into the object18to atomize the cleaning medium26. The vacuum24may vacuum the atomized cleaning medium26and the dislodged debris30(e.g., debris particles held within the cleaning medium26).

As used herein, close proximity may include a position close to the surface16of the object18without touching the object18. As an example, close proximity may include positions of at most approximately 12 inches from the surface16. As another example, close proximity may include positions of at most approximately 6 inches from the surface16. As another example, close proximity may include positions of at most approximately 3 inches from the surface16. As another example, close proximity may include positions of at most approximately 1 inch from the surface16. As yet another example, close proximity may include positions as close to the surface16as possible without contacting the surface16.

Those skilled in the art will appreciate that the proximity to the surface16of the object18may depend upon the size, power and/or configuration of the ultrasonic devices20, the cleaning medium dispenser22, the vacuum24, the ultrasonic devices58and/or the ultrasonic devices126in order to effectively perform a cleaning operation.

Referring toFIG. 7, in an example implementation, the holding fixture56may include at least one object holding fixture66configured to engage at least a portion (e.g., an edge) of the object18to secure the object18to the holding fixture56and fix the position of the object18. For example, each object holding fixture66may include an edge holding fixture80to engage at least one edge of the object18(e.g., an aircraft wing panel).

An ultrasonic device58may be coupled to each of the object holding fixtures66to transfer ultrasonic waves62(e.g., vibrations) (FIG. 6) through the object holding fixtures66and into the object18. Each ultrasonic device58may be physically coupled to the object holding fixtures66(e.g., a contact ultrasonic transducer) or air coupled to the object holding fixtures66(e.g., a non-contact ultrasonic transducer). The object holding fixtures66, including any edge holding fixtures80, may be acoustically coupled to the holding fixture56and the object18such that the ultrasonic waves62applied to the object holding fixtures66sufficiently transfer between and through the holding fixture56, the object holding fixtures66and into the object18.

As used herein, acoustically coupled means that all parts and/or components of the holding fixture56are connected together such that the entire construction is acoustically available (e.g., an acoustically resonating system) for effective transmission and propagation of ultrasonic waves62. For example, the holding fixture56may be constructed such that no gaps occur between components and the propagation of ultrasonic waves62is not lost through component and/or surface interfaces.

Referring toFIG. 8, in another implementation, the object18may be mounted to a support base68. The object18may be in contact with the support base68or may be spaced apart a predetermined distance from the support base68. The holding fixture56may include at least one support base holding fixture70configured to engage at least a portion of the support base68to secure the support base68to the holding fixture56and fix the position of the object18.

An ultrasonic device58may be coupled to each of the support base holding fixtures70to transfer ultrasonic waves62(FIG. 6) through the support base holding fixtures70, through the support base68and into the object18. The ultrasonic devices58may be physically coupled to the support base holding fixtures70or air coupled to the support base holding fixtures70. The support base holding fixtures70may be acoustically coupled to the holding fixture56and the support base68such that the ultrasonic waves62applied to the support base holding fixtures70sufficiently transfer between and through the holding fixture56, the support base holding fixtures66, the support base68and into the object18. Any object holding fixtures66, including any edge holding fixtures80, may similarly be acoustically coupled to the holding fixture56.

Referring toFIG. 9, in yet another example construction, the object18may be mounted to the support base68and the holding fixture56may include at least one object holding fixture66and at least one support base holding fixture70to secure the support base68and the object18to the holding fixture56and fix the position of the object18with respect to the cleaning head32and/or the movable assembly112(e.g., the robotic assembly34).

An ultrasonic device58may be coupled to each of the object holding fixtures66and each of the support base holding fixtures70to transfer ultrasonic waves62(FIG. 6) through the object holding fixtures66and the support base holding fixtures70, through the support base68and into the object18. The ultrasonic devices58may be physically coupled to the object holding fixtures66and the support base holding fixtures70or air coupled to the object holding fixtures66and the support base holding fixtures70. The object holding fixtures66and the support base holding fixtures70may be acoustically coupled to the holding fixture56and the support base68such that the ultrasonic waves62applied to the object holding fixtures66and the support base holding fixtures70sufficiently transfer between and through the holding fixture56, the object holding fixtures66, the support base holding fixtures66, the support base68and into the object18.

The object holding fixtures66and/or the support base holding fixtures70may be integral to the holding fixture56or may be installed on or connected to the holding fixture56. The ultrasonic generator72(FIG. 6) may be integral to the holding fixture56or may be remote and electrically coupled to the ultrasonic devices58.

Thus, in concert with the ultrasonic devices58, the object holding fixtures66and/or the support base holding fixtures70may form an acoustically resonating system that delivers ultrasonic waves62(e.g., vibrations) into and through the entire object18. A plurality of ultrasonic devices58may be arranged in any configuration (e.g., in an array of ultrasonic devices58). Each ultrasonic device58may have a fixed position or may be movable with respect to the holding fixture56, the object holding fixtures66and/or the support base holding fixtures70. For example, the position, orientation and/or location of the ultrasonic devices58may be manually movable or electromechanically movable. By placing, activating and tuning the ultrasonic devices58, various types of guided ultrasonic waves62may be created on the surface16of the object18at desired locations (e.g., cleaning zones54). For example, the ultrasonic waves62may create acoustic streaming within the cleaning medium26(e.g., movement of the cleaning fluid in response to the ultrasonic waves62).

Referring toFIG. 10, in another aspect, the disclosed system may include holding fixture56configured to hold and/or support the object18and at least one ultrasonic device58coupled to the holding fixture56. The ultrasonic devices58may deliver ultrasonic waves62to the object18through the holding fixture56. At least one ultrasonic generator72may supply energy to the ultrasonic devices58. An ultrasonic supply line74may couple the ultrasonic generator72to the ultrasonic devices58such that ultrasonic waves62may be applied through the entire object18.

At least one ultrasonic device126may be attached to the holding fixture56. The ultrasonic devices126may deliver ultrasonic waves128to the object18. At least one ultrasonic generator130may supply energy to the ultrasonic devices126. An ultrasonic supply line135may couple the ultrasonic generator130to the ultrasonic devices126such that ultrasonic waves128may be applied to the surface16of the object18. The ultrasonic generator130may be integral to the holding fixture56or may be remote and coupled to the ultrasonic devices126.

Each ultrasonic device58and each ultrasonic device126may be an ultrasonic transducer that converts energy into ultrasound. For example, the ultrasonic device58and ultrasonic device126may be a piezoelectric transducer that converts electrical energy into sound.

The cleaning head32may include only the cleaning medium dispenser22and the vacuum24. During a cleaning operation, the cleaning head32may be positioned in close proximity to (e.g., close to but not in contact with) the surface16of the object18, for example by the movable assembly112(e.g., the robotic assembly34). The cleaning medium26may be delivered to the surface16of the object18(e.g., about the cleaning zone54) from the cleaning medium dispenser22to dislodge debris30on the surface16. The ultrasonic waves62generated by the ultrasonic devices58of the holding fixture56and delivered into the object18may work in concert with the ultrasonic waves128generated by the ultrasonic devices126and delivered to the surface16of the object18to atomize the cleaning medium26. The vacuum24may vacuum the atomized cleaning medium26and the dislodged debris30(e.g., debris particles held within the cleaning medium26).

Referring toFIG. 11, in an example implementation, the object18may be mounted to the support base68. The holding fixture56may include at least one support base holding fixture70to engage at least a portion of the support base68to secure the support base68to the holding fixture56and fix the position of the object18. The holding fixture56may include at least one object holding fixture66to engage at least a portion (e.g., an edge) of the object18to secure the object18fix the position of the object18.

An ultrasonic device58may be coupled to each of the support base holding fixtures70to transfer ultrasonic waves62(FIG. 10) through the support base holding fixtures70, through the support base68and into the object18. The ultrasonic devices58may be physically coupled to the support base holding fixtures70or air coupled to the support base holding fixtures70. The support base holding fixtures70may be acoustically coupled to the holding fixture56and the support base68such that the ultrasonic waves62applied to the support base holding fixtures70sufficiently transfer between and through the holding fixture56, the support base holding fixtures70, the support base68and into the object18. Similarly, the object holding fixtures66, including any edge holding fixtures80, may be acoustically coupled to the holding fixture56.

Each ultrasonic device126may be an air coupled (e.g., non-contact) ultrasonic transducer. One or more ultrasonic devices126may be attached to the holding fixture56, for example, to the object holding fixtures66, by one or more ultrasonic device holding fixtures132. A plurality of ultrasonic devices126may be positioned and/or arranged in any configuration (e.g., in an array of ultrasonic devices126) set apart from the cleaning head32. The ultrasonic device holding fixture132may provide for position adjustability of the ultrasonic devices126. For example, the ultrasonic devices126may be positioned on opposing sides of the location of the cleaning head32and may move along with the cleaning head32during a cleaning operation.

Referring toFIG. 12, the ultrasonic device holding fixture132may be movably connected to the holding fixture56. The ultrasonic holding fixture132may provide for movement of the ultrasonic devices126along at least two axes. For example, the ultrasonic device holding fixture132may be movably connected to the object holding fixtures66and movable along an X-axis (e.g., in the direction of arrow134). The ultrasonic devices126may be movably connected to the ultrasonic device holding fixture132and movable along a Y-axis (e.g., in the direction of arrow136).

The ultrasonic device holding fixture132and the ultrasonic devices126may be manually movable or may be automatically or semi-automatically movable (e.g., by an electromechanical drive mechanism (not shown)).

Referring toFIG. 13, in an example implantation, the cleaning head32may include the vacuum chamber98having an open end100. The size of the cleaning zone54may be determined by area covered by the cleaning medium26, the vacuum airflow50and ultrasonic waves62and/or ultrasonic waves128. The cleaning medium dispenser22may be located within the vacuum chamber98at an orientation sufficient to deliver the cleaning medium26to the surface16of the object18. The vacuum24(FIG. 10) may be fluidly coupled to the vacuum supply line52to provide vacuum suctioning (e.g., vacuum airflow50) within the vacuum chamber98and/or to the surface16of the object18.

The ultrasonic devices58and ultrasonic devices126(FIG. 10) may be configured to generate a variety of different types of ultrasonic waves62applied into the object18and ultrasonic waves128applied to the surface16of the object18, respectively, including, but not limited to, longitudinal waves, shear waves, surface waves and/or plate waves. For example, ultrasonic device58may generate longitudinal and/or shear waves62in the object18and ultrasonic devices126may generate surface and/or plate waves128on the surface16of the object18.

Those skilled in the art will appreciate that any individual ultrasonic device20, ultrasonic device58, ultrasonic device126and/or combinations of ultrasonic devices20,58and126(FIG. 6) 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 object18and/or surface waves and/or plate waves on the surface16of the object18).

For example, the different types of ultrasonic waves28, ultrasonic waves62and ultrasonic waves128(FIG. 6) (e.g., longitudinal waves, shear waves, surface waves and/or plate waves) may be generated by adjusting the angles of incidence of the ultrasonic devices20, ultrasonic devices58and ultrasonic devices128(FIG. 6) relative to the surface16of the object18. As an example, positioning (e.g., rotating) the ultrasonic device approximately 10° from normal (e.g., from the plane of the surface16) may generate plate waves perpendicular to and on the surface16of the object18. As another example, positioning (e.g., rotating) the ultrasonic device approximately 0° from normal (e.g., parallel to the plane of the surface16) may generate longitudinal waves in the object18. As another example, shear waves may be generated under any angle of incidence and may propagate perpendicularly relative to the wave into the object18. As yet another example, surface waves may be generated under any angle of incidence and may propagate concentrically (e.g., elliptically) on the surface16of the object18.

Referring toFIGS. 14 and 15, in an example implementation, one or more three-dimensional cleaning zones54(e.g., an ultrasonic interaction volume140) may be formed around a complex object18(e.g., a mounting clip) by the interference of a plurality of focused ultrasonic waves.

As an example and best illustrated inFIG. 14, a plurality of air coupled ultrasonic devices126(e.g., such as the ultrasonic devices126shown and described inFIGS. 10-12) may be located in relative close proximity to (e.g., between approximately 1 and 12 inches from) the object18. The cleaning head32(e.g., such as the cleaning head32shown and described inFIGS. 10-12) may be located in relative close proximity (e.g., between approximately 1 and 12 inches from) to the object18. The cleaning head32may deliver cleaning medium26(e.g., steam) to one or more surfaces16of the object18to dislodge debris30from the surfaces16of the object18. The ultrasonic devices126may generate ultrasonic waves128a(e.g., longitudinal waves and/or shear waves in the object18) and ultrasonic waves128b(e.g., plate waves and/or shear waves on the surface16of the object18) to atomize the cleaning medium26and debris30(e.g., debris particles retained by the cleaning medium26). The vacuum24may provide vacuum suctioning (e.g., vacuum airflow50) within the vacuum chamber98and/or to the surface16of the object18to remove the atomized cleaning medium26and debris30.

The plurality of ultrasonic devices126(e.g., an array of ultrasonic device126) may emit the ultrasonic waves128aand128b, which are focused toward the object18and interfere with each other at the object18. The interfering ultrasound waves128aand128bmay form the ultrasound interaction volume140around the object18, which generates the longitudinal waves and/or shear waves in the object18and the plate waves and/or shear waves on the surface16of the object18.

As another example (not shown), the object18(e.g., having a relatively complex three-dimensional surface16) may be mounted to a holding fixture (e.g., the holding fixture56shown and described inFIGS. 6-9). A plurality of ultrasonic devices126may generate ultrasonic waves128directed to the object18. A plurality of ultrasonic devices (e.g., ultrasonic devices58shown and described inFIGS. 6-9) may generate ultrasonic waves62directed through the holding fixture56and into the object18. The interference of ultrasonic waves128and ultrasonic waves62may generate the longitudinal waves and/or shear waves in the object18and the plate waves and/or shear waves on the surface16of the object18to atomize the cleaning medium26and debris30(e.g., debris particles retained by the cleaning medium26). The vacuum24may provide vacuum suctioning (e.g., vacuum airflow50) within the vacuum chamber98and/or to the surface16of the object18to remove the atomized cleaning medium26and debris30.

The plurality of ultrasonic devices126(e.g., an array of ultrasonic device126) may emit the ultrasonic waves128and the plurality of ultrasonic devices58(e.g., an array of ultrasonic devices58) may emit the ultrasonic waves62, which are focused toward the object18and interfere with each other at the object18. The interfering ultrasound waves128and62may form the ultrasound interaction volume140around the object18, which generates the longitudinal waves and/or shear waves in the object18and the plate waves and/or shear waves on the surface16of the object18.

As yet another example and best illustrated inFIG. 15, a plurality of air coupled ultrasonic devices126(e.g., such as the ultrasonic devices126shown and described inFIGS. 10-12) may be located in relative close proximity to the object18. The cleaning head32(e.g., such as the cleaning head32shown and described inFIGS. 1-5) may be located in relative close proximity to the object18. The cleaning head32may deliver cleaning medium26(e.g., steam) to one or more surfaces16of the object18to dislodge debris30from the surfaces16of the object18. The ultrasonic devices126may generate ultrasonic waves128directed to the object18(e.g., longitudinal waves and/or shear waves in the object18). A plurality of ultrasonic devices20located with the cleaning head32(e.g., the ultrasonic devices20shown and described inFIGS. 1-5) may generate ultrasonic waves28directed to the object18(e.g., surface waves and/or plate waves on the surface of the object18). The interference of ultrasonic waves128and ultrasonic waves28may generate the longitudinal waves and/or shear waves in the object18and the plate waves and/or shear waves on the surface16of the object18to atomize the cleaning medium26and debris30(e.g., debris particles retained by the cleaning medium26). The vacuum24may provide vacuum suctioning (e.g., vacuum airflow50) within the vacuum chamber98and/or to the surface16of the object18to remove the atomized cleaning medium26and debris30.

The plurality of ultrasonic devices126(e.g., an array of ultrasonic device126) may emit the ultrasonic waves128and the plurality of ultrasonic devices20(e.g., an array of ultrasonic devices20) may emit the ultrasonic waves28, which are focused toward the object18and interfere with each other at the object18. The interfering ultrasound waves128and28may form the ultrasound interaction volume140around the object18, which generates the longitudinal waves and/or shear waves in the object18and the plate waves and/or shear waves on the surface16of the object18.

Referring toFIGS. 16 and 17, the disclosed system10may be configured to clean one or more confined surfaces16(e.g., interior surfaces) of an object18. For example, the system10may be configured to clean interior surfaces16of the object18, such as those located within a confined space142within the interior of the object18(e.g., interior surfaces of a wing box of an airplane fuel tank).

Referring toFIG. 16, in another implementation, the disclosed system10may include a handheld cleaning head32. The cleaning head32(e.g., the cleaning head32shown and described inFIGS. 1-5) may include at least one cleaning medium dispenser22to deliver cleaning medium26to the surface16of the object18, at least one air coupled ultrasonic device20to emit ultrasonic waves28to the surface16of the object18and at least one vacuum24to provide a vacuum airflow50to the surface16of the object18.

The movable assembly112may be one or more cart assemblies116. The cart assembly116may house the ultrasonic generator40, the cleaning medium source44and the vacuum source48. The cleaning head32may be functionally coupled to the cart assembly116by the supply line82. For example, the ultrasonic supply line42may be coupled to the ultrasonic devices20, the cleaning medium supply line46may be fluidly coupled to the cleaning medium dispenser22and the vacuum supply line52may be fluidly coupled to the vacuum24.

During a cleaning operation, an operator146may be located within the confined space142and the cleaning head32may be introduced within the confined space142, for example through an access port144in the object18. The cleaning head32may be manually positioned in relatively close proximity to the surface16of the object18to be cleaned. The effective position of the cleaning head32relative to the surface16may be determined visually. For example, the effective position of the cleaning head32relative to the surface16may be determined by when the cleaning medium26and debris30begin to and/or fully atomize from the surface16. Optionally, the operator146may be positioned on an ultrasonic acoustic absorber148to maintain an acoustically resonate system and protect the operator146from ultrasonic vibrations.

A plurality of ultrasonic devices20(e.g., an array of ultrasonic devices20) may emit ultrasonic waves28, for example from the cleaning head32, directed toward the surface16and into the object18. The ultrasonic waves28may be focused toward the surface16of the object18and generates the longitudinal waves and/or shear waves in the object18and/or the plate waves and/or shear waves on the surface16of the object18(e.g., ultrasonic vibrations in the object18) to atomize the cleaning medium26and debris30(e.g., debris particles retained by the cleaning medium26). The vacuum24may vacuum the atomized cleaning medium26and debris30.

Optionally, a plurality of air coupled ultrasonic devices126(e.g., the ultrasonic devices shown and described inFIGS. 10-12) may be located in relatively close proximity to the surface16of the object18. For example, the ultrasonic devices126may be positioned generally opposite the location of the cleaning head32and the ultrasonic devices20(e.g., an opposing surface150). The ultrasonic devices126may be connected to one or more ultrasonic device holding fixtures132. The ultrasonic holding fixtures132may provide for manual or electromechanical movement and positioning of the ultrasonic devices126relative to the object18, such that the ultrasonic devices126may move alone with the cleaning head32.

A plurality of ultrasonic devices20(e.g., an array of ultrasonic devices20) may emit ultrasonic waves28directed toward the surface16and into the object18. A plurality of ultrasonic devices126(e.g., an array of ultrasonic devices126) may emit ultrasonic waves128toward the opposing surface150and into the object18. The ultrasonic waves28and the ultrasonic waves128may be focused toward the surface16of the object18and interfere with each other about the cleaning zone54(FIG. 6) of the object18. The interfering ultrasound waves28and128may generates the longitudinal waves and/or shear waves in the object18and/or the plate waves and/or shear waves on the surface16of the object18(e.g., ultrasonic vibrations in the object18) to atomize the cleaning medium26and debris30(e.g., debris particles retained by the cleaning medium26). The vacuum24may vacuum the atomized cleaning medium26and debris30.

Referring toFIG. 17, in another implementation, the cleaning head32may be mounted to a telescopic boom assembly152. The cleaning head32(e.g., the cleaning head32shown and described inFIGS. 1-6) may include at least one cleaning medium dispenser22to deliver cleaning medium26to the surface16of the object18, at least one air coupled ultrasonic device20to emit ultrasonic waves28to the surface16of the object18and at least one vacuum24to provide a vacuum airflow50to the surface16of the object18.

The movable assembly112may be one or more cart assemblies116and the telescopic boom assembly152. The cart assembly116may house the ultrasonic generator40, the cleaning medium source44and the vacuum source48. The cleaning head32may be functionally coupled to the cart assembly116by the supply line82. For example, the ultrasonic supply line42may be electrically coupled to the ultrasonic devices20, the cleaning medium supply line46may be fluidly coupled to the cleaning medium dispenser22and the vacuum supply line52may be fluidly coupled to the vacuum24.

The telescopic boom assembly152may be configured to automatically or semi-automatically move and position the cleaning head32with respect to the surface16to be cleaned within the confined space142. The telescopic boom assembly152may be rotatable and articulated. For example, the telescopic boom assembly152may include a riser stand156and at least one telescopic arm154movably connected to the riser stand156. The cleaning head32may be connected to an end of the telescopic arm154, for example at an end effector160. An actuator158may automatically adjust the position of the cleaning head32by extending and/or retracting the telescopic arm154.

During a cleaning operation, the telescopic arm154of the telescopic boom assembly152and the cleaning head32may be located within the confined space142, for example introduced within the confined space142through the access port144in the object18. The cleaning head32may be automatically or semi-automatically positioned in relative close proximity to the surface16of the object18to be cleaned, for example by actuating the telescopic arm154and/or the end effector160.

A plurality of ultrasonic devices20(e.g., an array of ultrasonic devices20) may emit ultrasonic waves28, for example from the cleaning head32, directed toward the surface16and into the object18. The ultrasonic waves28may be focused toward the surface16of the object18and generate the longitudinal waves and/or shear waves in the object18and/or the plate waves and/or shear waves on the surface16of the object18(e.g., ultrasonic vibrations in the object18) to atomize the cleaning medium26and debris30(e.g., debris particles retained by the cleaning medium26). The vacuum24may vacuum the atomized cleaning medium26and debris30.

Optionally, a plurality of air coupled ultrasonic devices126(e.g., the ultrasonic devices shown and described inFIGS. 10-12) may be located in relatively close proximity to the surface16of the object18. For example, the ultrasonic devices126may be positioned generally opposite the location of the cleaning head32and the ultrasonic devices20(e.g., an opposing surface150). The ultrasonic devices126may be connected to one or more ultrasonic device holding fixtures132. The ultrasonic holding fixtures132may provide for manual or electromechanical movement and positioning of the ultrasonic devices126relative to the object18, such that the ultrasonic devices126may move along with the cleaning head32.

A plurality of ultrasonic devices20(e.g., an array of ultrasonic devices20) may emit ultrasonic waves28directed toward the surface16and into the object18. A plurality of ultrasonic devices126(e.g., an array of ultrasonic devices126) may emit ultrasonic waves128toward the opposing surface150and into the object18. The ultrasonic waves28and the ultrasonic waves128may be focused toward the surface16of the object18and interfere with each other about the cleaning zone54(FIG. 1) of the object18. The interfering ultrasound waves28and128may generates the longitudinal waves and/or shear waves in the object18and/or the plate waves and/or shear waves on the surface16of the object18(e.g., ultrasonic vibrations in the object18) to atomize the cleaning medium26and debris30(e.g., debris particles retained by the cleaning medium26). The vacuum24may vacuum the atomized cleaning medium26and debris30.

Thus, the disclosed system10may be utilized in a variety of different configurations dependent upon a given cleaning operation and type of object18being cleaned. For example, the object18and all of the ultrasonic devices (e.g., ultrasonic devices58and126) may be stationary and the cleaning head32(e.g., including the cleaning medium dispenser22and the vacuum24) may move in one or more directions (e.g., alongside the object18in the X and/or Y directions).

As another example, the object18and particular ultrasonic devices (e.g., ultrasonic devices58and126) may be stationary and the cleaning head32(e.g., including the ultrasonic devices20, the cleaning medium dispenser22and the vacuum24) and certain ultrasonic devices (e.g., ultrasonic devices126) may move in one or more directions (e.g., alongside the object18in the X and/or Y directions).

As another example, the object18may be stationary and the cleaning head32(e.g., including the ultrasonic devices20, the cleaning medium dispenser22and the vacuum24) and all of the ultrasonic devices (e.g., ultrasonic devices58and126) may move in one or more directions (e.g., alongside the object18in the X and/or Y directions).

As another example, the object18, the cleaning head32(e.g., including the ultrasonic devices20, the cleaning medium dispenser22and the vacuum24) and all of the ultrasonic devices (e.g., ultrasonic devices58and126) may move one or more directions. As yet another example, the cleaning head32(e.g., including the ultrasonic devices20, the cleaning medium dispenser22and the vacuum24) and all of the ultrasonic devices (e.g., ultrasonic devices58and126) may be stationary and the object18may move in one or more directions (e.g., alongside the cleaning head32and/or the ultrasonic devices in the X and/or Y directions).

The size, quantity, location, relative position, orientation angle, and distance from the surface16of the object18(e.g., the cleaning zone54) may be considered when sizing and configuring the ultrasonic devices20,58and126for 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 toFIG. 18, one aspect of the disclosed method, generally designated200, for surface cleaning of an object may begin at block202by providing an object having at least one surface to be cleaned.

As shown at block206, 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 block208, 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 block204, 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 block210, 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 block212, the ultrasonic waves may be focused on a cleaning zone on the surface of the object. As shown at block214, the focused waves may generate a pattern of ultrasonic vibrations on the surface of the object and/or in the object.

As shown at block216, 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 block218, 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 block220, 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 toFIGS. 1, 6 and 10, the various aspects of the disclosed system10for cleaning an object including a surface may include a cleaning medium dispenser22configured to deliver a cleaning medium26to the surface16of the object18, wherein the cleaning medium26may dislodge and capture debris30from the surface, an ultrasonic device20configured to deliver ultrasonic waves to the object30, wherein the ultrasonic waves28atomize the cleaning medium26and captured debris30from 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 waves28may generate ultrasonic vibrations on the surface16of the object18. The ultrasonic waves28may generate ultrasonic vibrations in the object18. The ultrasonic waves28may include at least one of longitudinal waves, shear waves, surface waves and plate waves. The ultrasonic waves28may be focused to a cleaning zone54on the surface16of the object18.

In another aspect, the position of the cleaning medium dispenser22, the ultrasonic device20and the vacuum24may be adjustable with respect to the surface16of the object18. The cleaning medium dispenser22, the ultrasonic device20and the vacuum may be mounted to a cleaning head32. The cleaning head32may be mounted to a movable assembly112, wherein the movable assembly112may position the cleaning head32relative to the surface16.

In another aspect, the disclosed system10may include a holding fixture56configured to hold the object18, wherein the holding fixture56defines an acoustically resonating system, and wherein the ultrasonic waves28generate ultrasonic vibrations in the object18. The ultrasonic device20may be coupled to the holding fixture and the cleaning medium dispenser22and the vacuum24may be mounted to the cleaning head32. The ultrasonic device20may be coupled to the holding fixture56and a position of the cleaning medium dispenser22and the vacuum24may be adjustable with respect to the object18. The ultrasonic device20may be physically coupled to the holding fixture56. The ultrasonic device20may be air coupled to at least one of the holding fixture56and the object18.

In another aspect, the cleaning medium dispenser22, the ultrasonic device20and the vacuum24may be mounted to the cleaning head32. The holding fixture56may include a second ultrasonic device58configured to deliver second ultrasonic waves62through the holding fixture54and into the object18. The ultrasonic waves28and the second ultrasonic waves62may generate ultrasonic vibrations in the object18to atomize the cleaning medium26from the surface16. The holding fixture56may be a part of the object18.

In another aspect, the disclosed system10may include a second ultrasonic device58,126configured to deliver second ultrasonic waves62,128to the object18. The ultrasonic device20may be air coupled to the object18. The second ultrasonic device128may be air coupled to the object18. Interference of the ultrasonic waves28and the second ultrasonic waves128may define an ultrasonic interaction volume140around at least a portion of the surface16.

In one aspect, the holding fixture56may be configured to hold the object18. The holding fixture56may an acoustically resonating system. The ultrasonic waves28and the second ultrasonic waves62may generate ultrasonic vibrations in the object18to atomize the cleaning medium26from the surface16. The second ultrasonic device58may be physically coupled to the holding fixture56. The ultrasonic device20may be air coupled to at least one of the object18and the holding fixture56.

In another aspect, the disclosed system10may include a plurality of ultrasonic devices20,58,126arranged in an acoustic array. The plurality of ultrasonic devices20,58,126may deliver ultrasonic waves28,62,128to the object18. The ultrasonic waves28,62,128may generate a pattern of ultrasonic vibrations in the object18. The acoustic array may include at least one of a parametric array and a phased array. The plurality of ultrasonic devices20,126may be air coupled to the object18.

In another aspect, the holding fixture56may be configured to hold the object18. The holding fixture56may define an acoustically resonating system. At least a portion of a plurality of ultrasonic devices58may be physically coupled to the holding fixture56. At least a portion of a plurality of ultrasonic devices20,126may be air coupled to at least one of the holding fixture56and the object18.

In another aspect, the cleaning medium26may disintegrate and dislodge the debris30from the surface. The ultrasonic waves may reduce adhesion between the surface16and the debris30. The cleaning medium26may include a fluid. The fluid may include at least one of a liquid and a gas. The cleaning medium26may include at least one of steam, water, and an aqueous solution.

Referring generally toFIGS. 1, 6, 10 and 18, one aspect of the disclosed method200for cleaning an object including a surface may include the steps of: (1) delivering the cleaning medium26to the surface16of the object18, (2) delivering ultrasonic waves28,62,128to the object18to atomize the cleaning medium26, and (3) applying a vacuum airflow50to collect atomized cleaning medium26. The ultrasonic waves28,62,128may generate ultrasonic vibrations in the object18.

In another aspect, the disclosed method200may include the steps of: (4) mounting the object18to the holding fixture56, wherein the holding fixture56may define an acoustically resonating system, and (5) delivering the ultrasonic waves28,62,128to at least one of the holding fixture56and the object18to generate ultrasonic vibrations in the object18.

In another aspect, the disclosed method200may include the steps of: (6) focusing the ultrasonic waves28,62,128on the cleaning zone54on the surface16of the object18, and (7) generating a pattern of ultrasonic vibrations in the object18. The step of generating the pattern of ultrasonic vibrations may include defining an ultrasonic interaction volume140around at least a portion of the surface16through interference of the ultrasonic waves28,62,128.

In another aspect, the cleaning medium26may disintegrate and dislodge debris30from the surface16. The cleaning medium26may include at least one of a liquid and a gas. The ultrasonic waves28,62,128may reduce adhesion between the surface16and the debris30.

Examples of the disclosure may be described in the context of an aircraft manufacturing and service method300, as shown inFIG. 19, and an aircraft302, as shown inFIG. 20. During pre-production, the aircraft manufacturing and service method300may include specification and design304of the aircraft302and material procurement306. During production, component/subassembly manufacturing308and system integration310of the aircraft302takes place. Thereafter, the aircraft302may go through certification and delivery312in order to be placed in service314. While in service by a customer, the aircraft302is scheduled for routine maintenance and service316, which may also include modification, reconfiguration, refurbishment and the like.

As shown inFIG. 20, the aircraft302produced by example method300may include an airframe318with a plurality of systems320and an interior322. Examples of the plurality of systems320may include one or more of a propulsion system324, an electrical system326, a hydraulic system328, and an environmental system330. Any number of other systems may be included. Although an aerospace example is shown, the principles of the disclosed system10and method200may 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 method300. For example, components or subassemblies corresponding to component/subassembly manufacturing308, system integration310, and or maintenance and service316may be fabricated or manufactured using the disclosed system10(FIGS. 1, 6 and 10) and method200(FIG. 18). Also, one or more apparatus examples, method examples, or a combination thereof may be utilized during component/subassembly manufacturing308and/or system integration310, for example, by substantially expediting assembly of or reducing the cost of an aircraft302, such as the airframe318and/or the interior322. Similarly, one or more of apparatus examples, method examples, or a combination thereof may be utilized while the aircraft302is in service, for example and without limitation, to maintenance and service316.

Although various aspects of the disclosed system and method have been shown and described, modifications may occur to those skilled in the art upon reading the specification. The present application includes such modifications and is limited only by the scope of the claims.