Patent Description:
In a manufacturing environment, such as, for example, the manufacture of aircraft, various parts or components may be connected to each other to form structures or substructures. Installation of mechanical fasteners such as, for example, blind fasteners or one-side fasteners, is generally conducted in order that the fastener is in flush alignment (i.e., no gaps) to the surface of the part.

A blind fastener may include an internally threaded body and an externally threaded core bolt that may pass through the internally threaded body. One end of the core bolt has an enlarged head, while the other end has an engaging portion. Rotation of the core bolt relative to the body causes axial movement of the core bolt in an outwardly direction from the body. Such axial movement thereby causes deformation of the body outwardly in a manner that forms a bulb that engages an inner surface of the part, thereby securing the blind fastener in place and attaching the parts to each other. When installing a blind fastener, a portion of the head of the core bolt typically fractures leaving a flush surface on the installed fastener head.

The structural integrity of the connection between parts that is facilitated by the fastener may be compromised should the fastener have variability in its shape or size and/or the fastening hole of the part(s) to be fastened are offset due to machining tolerances.

Inspection of installed fasteners such as, for example blind fasteners or one-side fasteners is often difficult, if not impossible due to the fact that the relatively tight access spaces and/or enclosed location of the fasters make access to the "blind" side of the part(s) difficult and/or unavailable.

<CIT>, in accordance with its abstract, states an apparatus, method and system for inspecting a fastener installed in a structure including the illumination of a fastener and a portion of the structure surrounding the fastener, the detection of the light reflected from the fastener and the portion of the structure surrounding the fastener, the analysis of the reflected light, and the definition of at least one inspection criteria. The structure has a coating that reflects light of a predefined wavelength differently than the fastener. As such, the light that illuminates the fastener and the structure surrounding the fastener has a wavelength within the predefined range. The light reflected from the fastener and the portion of the structure surrounding the fastener is then detected and analyzed to determine an interface between exposed surfaces of the fastener and the coating.

<CIT>, in accordance with its abstract, states a method of sequentially performing a plurality of jointing operations including positioning an automated device to form a mechanical joint into a workpiece and forming a mechanical joint into the workpiece. Once the mechanical joint is formed, the workpiece is scanned to generate data indicating the surface geometry of the workpiece at a location including the mechanical joint. One or more geometric features of the surface geometry are identified, and if the identified geometric features are within respective predetermined specification thresholds, the automated device is repositioned to form a subsequent mechanical joint into the workpiece.

<CIT>, in accordance with its abstract, states a borescope for optically inspecting gas turbines, in particular aircraft engines. The borescope comprises an electronic image capturing unit as a borescope objective lens at the end of a shaft which is suitable for insertion into a borescope opening and suitable for exact positioning of the borescope objective lens relative to the borescope opening, data and supply lines for the image capturing unit being guided through said shaft. The image capturing unit has two spaced apart image capturing sensors, the recording cones of which overlap in a predefined recording plane to form a recording region in such a way that the image data from the two image capturing sensors can be processed into 3D data by triangulation.

<CIT>, states an anchor head that includes an insertion hole for, in the state of inserting one end of a tendon buried underground, retaining and locking the one end, and an inspection hole for allowing the inspection of a background area of the anchor head by visual observation through a CCD camera.

A method of inspecting one or more structural features (e.g., blind bulb, nut, collar, pin protrusion, thin sleeve protrusion) of a fastener previously installed in a fastening hole of a structure or substructure is provided according to claim <NUM>. Such methods may serve the purpose of maintaining the structural integrity of any connection between parts that is facilitated by the fastener.

In accordance with one or more embodiments, the structural features can include, but are not limited to, retention features of the installed fastener and other installed fasteners in an inspection environment external to the installed fastener. As used herein, the "retention feature(s)" may include a bulb portion of the fastener that engages an inner surface of the part forming the structure or substructure to maintain or secure the fastener in the fastening hole.

In accordance with one or more embodiments, provided herein is a manually-operated or automated apparatus and manually-operated or automated system for inspecting one or more structural features of a fastener in a structure or substructure. Such features for inspection may include, but are not limited to, a fastener head, a blind fastener bulb, a nut-and-pin protrusion, a swaged collar, a bracket, an insert, a clip, a trimmed or machined feature, etc..

The inspection apparatus and inspection system may respectively be configured for entry into/through a hole, notch, access opening, and the like. In an embodiment in which the inspection apparatus and inspection system is to inspect a blind fastener installation, the inspection apparatus and inspection system may be configured for entry into/through an adjacent drilled hole.

In accordance with one or more embodiments, a method of inspecting a fastener installed in a fastening hole of a region of a structure that is enclosed or has limited access may comprise one or more of the following: positioning an inspection apparatus for entry along a longitudinal axis thereof through an adjacent fastening hole of the installed fastener to be inspected; and detecting structural features of one or more of the fastener and an inspection environment external to the fastener as inspection data.

In accordance with one or more not claimed examples, an inspection apparatus for inspecting a fastener installed in a fastening hole of a region of a structure that is enclosed or has limited access may comprise one or more of the following: an inspection member, positioned for entry along a longitudinal axis thereof through an adjacent fastening hole of the installed fastener to be inspected; a sensor array, arranged in the inspection member, the sensor array comprising one or more sensors to detect structural features of one or more of the installed fastener and an inspection environment external to the installed fastener as inspection data; and a control module, arranged in the inspection member, the control module comprising one or more processors configured to control the inspection member and the sensor array.

An inspection system of inspecting a fastener installed in a fastening hole of a region of a structure that is enclosed or has limited access may comprise one or more of the following is provided according to claim <NUM>: an automation machine configured to conduct one or more of drilling one or more fastening holes in the structure, and installing a fastener in a corresponding fastening hole; and an inspection apparatus, operatively connected to the automation machine, the inspection apparatus including: an inspection member, positioned for entry along a longitudinal axis thereof through an adjacent fastening hole of the installed fastener to be inspected; and a sensor array, arranged in the inspection member, the sensor array comprising one or more sensors to detect structural features of one or more of the installed fastener and an inspection environment external to the installed fastener as inspection data; and a control module, arranged in the inspection member, the control module comprising one or more processors configured to control the inspection member and the sensor array.

In accordance with one or more examples not claimed , a computing system for inspecting a fastener installed in a fastening hole of a region of a structure that is enclosed or has limited access may comprise one or more of the following: one or more processors configured to: causing an inspection member, to detect structural features of one or more of the installed fastener and an inspection environment external to the installed fastener as inspection data; and controlling an inspection member and the sensor array.

Practice of the method and the system set forth, described, and/or illustrated herein facilitates via an adjacent fastener hole, non-invasive inspection of one or more structural features of a fastener previously installed in a fastening hole of a structure or substructure, and/or an inspection environment external to the fastener.

The features, functions, and advantages that have been discussed can be achieved independently in various embodiments or may be combined in yet other embodiments further details of which can be seen with reference to the following description and drawings.

The various advantages of the embodiments of the present disclosure will become apparent to one skilled in the art by reading the following specification and appended claims, and by referencing the following drawings, in which:.

As illustrated in <FIG>, in accordance with one or more embodiments, a manually-operated or automated inspection apparatus <NUM>, <NUM> and a manually-operated or automated inspection system <NUM> for inspecting one or more structural features of a fastener in a structure or substructure. Such features for inspection may include, but are not limited to, a fastener head, a blind fastener bulb, a nut-and-pin protrusion, a swaged collar, a bracket, an insert, a clip, a trimmed or machined feature, etc..

In accordance with one or more embodiments, the inspection apparatus <NUM>, <NUM> and the inspection system <NUM> for inspection of a fastener F, such as, for example, a blind fastener or a one-side fastener, that has been previously installed in a fastening hole HF of a structure S that includes an upper structure region Su and a lower structure region SL. Each inspection apparatus <NUM>, <NUM> may respectively comprise an inspection member <NUM>, <NUM> having at least one region thereof sized for entry into or receipt through an adjacent fastening hole HA or structure of the fastener F to be inspected or another fastener or structure S<NUM> to be inspected. Alternatively or additionally, the inspection apparatus <NUM>, <NUM> and the inspection system <NUM> may be used for installation verification or any inspection in the process.

The inspection member <NUM>, <NUM> may comprise a body that is configured for hand operation by a user for rework, maintenance, and/or in-service inspections. The inspection member <NUM>, <NUM> has a portable, compact structural configuration that permits manual and/or automated inspection in tightly confined or enclosed inspection regions of a structure. This disclosure contemplates the inspection member <NUM>, <NUM> having any suitable structural configuration that falls within the scope of the principles of this disclosure set forth herein. For example, as illustrated in <FIG>, the inspection apparatus <NUM>, <NUM> may be incorporated into an automation machine <NUM> to form an inspection system <NUM>. The automation machine <NUM> may have one or more other functions, such as, for example, drilling and fastening, or machining or assembly.

As illustrated in <FIG>, the inspection member <NUM> may have one or more regions, to include, for example, a base region 120A and an inspection region 120B extending longitudinally from the base region 120A. The base region 120A and the inspection region 120B may be operatively connected to permit selective rotation of the inspection region 120B about the longitudinal axis of the inspection member <NUM> and independent of the base region 120A.

The inspection apparatus <NUM>, <NUM> may further comprise one or more light source(s) <NUM>, <NUM>, a sensor array <NUM>, <NUM>, a power source <NUM>, <NUM> (e.g., a battery), an actuator <NUM>, <NUM> to manually activate the light source(s) <NUM>, <NUM> and/or sensor array <NUM>, <NUM>, a control module <NUM>, <NUM>, and one or more data stores <NUM>, <NUM>.

The one or more light source(s) <NUM>, <NUM> may be configured to emit illuminating light to the fastener F and an inspection environment E external to the fastener F. The inspection environment E may comprise one or more of the upper structure region SU, the lower structure region SL, another structure S2 (See, <FIG> and <FIG>) and one or more fasteners.

In accordance with one or more embodiments, the light source(s) <NUM>, <NUM> may comprise one or more LEDs operatively connected to a printed circuit board (PCB) mounted in an interior of the inspection member <NUM>, <NUM>, and the control module <NUM>, <NUM> to control an operating mode of one or more of the light source(s) <NUM>, <NUM>, the sensor array <NUM>, <NUM>, the power source <NUM>, <NUM>, and the actuator <NUM>, <NUM>. The light source(s) <NUM>, <NUM> may be arranged, mounted, or otherwise positioned at any suitable location with respect to the inspection member <NUM>, <NUM>. For example, one or more LEDs may be located within an interior space of the inspection member <NUM>, <NUM>, and/or one or more LEDs may be located on an exterior surface of the inspection member <NUM>, <NUM>. It will be understood that this disclosure contemplates that the one or more LEDs may be arranged, mounted, or otherwise positioned in any suitable that fall within the scope of the principles of this disclosure set forth herein.

In accordance with one or more embodiments, one or more LEDs may be controlled manually by a user or automatically by the control module <NUM>, <NUM> to simultaneously or sequentially emit illuminating light to one or more fasteners F and one or more inspection environments E in which the fasteners F are located. For example, one or more LEDs may be mounted spaced apart vertically along the longitudinal axis of the inspection member <NUM>, <NUM>. Alternatively or additionally, one or more LEDs may be mounted spaced apart radially around the longitudinal axis of the inspection member <NUM>, <NUM>.

The inspection member <NUM>, <NUM> may be controlled manually by a user or automatically by the control module <NUM>, <NUM> to selectively rotate (e.g., between <NUM> to <NUM>°) about its longitudinal axis to change an orientation of the light source(s) <NUM>, <NUM> during the inspection. For example, in an automated operating mode of the inspection apparatus <NUM>, <NUM>, the control module <NUM>, <NUM> may cause selective rotation of the inspection region 120B about the longitudinal axis of the inspection member <NUM> and independent of the base region 120A.

The sensor array <NUM>, <NUM> may comprise one or more sensors configured to, at least during operation of the inspection apparatus <NUM>, <NUM> detect, determine, assess, monitor, measure, quantify, and/or sense information about one or more of: the fastener F, the inspection environment E, other fasteners, and another structure S<NUM>. As set forth, described, and/or illustrated herein, "sensor" means any device, component, and/or system that can perform one or more of detecting, determining, assessing, monitoring, measuring, quantifying, and sensing one or more things in the inspection environment.

The information may comprise inspection data of the illuminated fastener F and the illuminated inspection environment E. To preserve the image quality provided by the sensor array <NUM>, <NUM> particularly in dark inspection regions, the brightness or illuminating intensity of light emitted by the light source(s) <NUM>, <NUM> may be dynamically adjusted by the control module <NUM>, <NUM>. The inspection member <NUM>, <NUM> may be configured for manual or automated rotation about its longitudinal axis to change an orientation of the sensor array <NUM>, <NUM> during the inspection.

In accordance with one or more embodiments, the sensor array <NUM>, <NUM> may comprise one or more sensors including, but not limited to, infrared sensors, ultrasonic sensors, acoustic sensors, proximity/position sensors, laser sensors, sonar sensors, motion sensors, heat sensors, and image sensors (e.g., cameras). The image sensor(s) may include an angled mirror to further facilitate compact arrangements which permit viewing of the fastener F, the inspection environment E, etc. The sensor array <NUM>, <NUM> may be controlled manually by a user or automatically by the control module <NUM>, <NUM> to detect, determine, assess, monitor, measure, quantify, and/or sense information about the inspection environment E in which the fastener F is located, including information about other fasteners and/or structures S<NUM> in the inspection environment E. It will be understood that this disclosure contemplates that the sensor array <NUM> may comprise other types of sensors that fall within the scope of the principles of this disclosure set forth herein.

The sensor array <NUM>, <NUM> may be arranged, mounted, or otherwise positioned at any suitable location with respect to the inspection member <NUM>, <NUM>. For example, one or more sensors may be located within an interior space of the inspection member <NUM>, <NUM> and/or one or more sensors may be located on an exterior surface of the inspection member <NUM>, <NUM>. It will be understood that this disclosure contemplates that the one or more sensors may be arranged, mounted, or otherwise positioned in any suitable that fall within the scope of the principles of this disclosure set forth herein.

In accordance with one or more embodiments, one or more sensors in the sensor array <NUM>, <NUM> may be controlled manually by a user or automatically by the control module <NUM>, <NUM> to simultaneously or sequentially detect, determine, assess, monitor, measure, quantify, and/or sense information about one or more fasteners F and one or more inspection environments E in which the fasteners F are located. For example, one or more sensors of the sensor array <NUM>, <NUM> may be mounted spaced apart vertically along the longitudinal axis of the inspection member <NUM>, <NUM>. Alternatively or additionally, one or more sensors of the sensor array <NUM>, <NUM> may be mounted spaced apart radially around the longitudinal axis of the inspection member <NUM>, <NUM>.

In accordance with one or more embodiments, the one or more sensors of the sensor array <NUM>, <NUM> may be controlled manually by a user or automatically by the control module <NUM>, <NUM> to operate independently from each other, or alternatively, in combination with each other. The one or more sensors in the sensor array <NUM>, <NUM> may be used in any combination, and may be used redundantly to validate and improve the accuracy of the sensor array <NUM>, <NUM>.

In accordance with one or more embodiments, the inspection data may comprise one or more of image data, measurement data, and spatial proximity/position data of the fastener F, the inspection environment E, another fastener, and/or another structure S<NUM>. Embodiments, however, are not limited thereto, and thus, this disclosure contemplates the inspection data comprising any information corresponding to one or more structural features (e.g., blind bulb, nut, collar, pin protrusion, thin sleeve protrusion, a fastener head, a nut-and-pin protrusion, a swaged collar, a bracket, an insert, a clip, a trimmed or machined feature, etc.) and spatial relationship(s) between the fastener F and the inspection environment E that falls within the scope of the principles of this disclosure set forth herein. The inspection data may particularly correspond to the dimensions (e.g., diameter, thickness, and/or height) of one or more structural features, such as, for example, a retention feature or bulb feature of the fastener F.

Alternatively or additionally, the inspection data may correspond to the structural dimensions (e.g., diameter) of an adjacent fastening hole HA. For example, to measure the diameter of the hole HA, the apparatus <NUM>, <NUM> may be configured to make the hole diameter measurement (in a manual mode and/or an automated mode) by being caused to rotate simultaneously with moving forward linearly while entering the hole HA (e.g., before conducting the inspection), or while exiting from the hole HA (e.g., after conducting the inspection), or offset while entering into the hole HA, or offset while exiting from the hole HA. Alternatively or additionally, the inspection data may correspond to an interface gap between the retention feature or bulb feature and the surface of the structure S.

As illustrated in <FIG>, the control module <NUM>, <NUM> is operatively connected to one or more data stores <NUM>, <NUM>. The control module <NUM>, <NUM> may include a set of logic instructions executable by one or more processors of the control module <NUM>, <NUM> or a source (e.g., a computing device <NUM>, <NUM>) arranged external to the control module <NUM>, <NUM>. Alternatively or additionally, the data stores <NUM>, <NUM> may contain such logic instructions. The logic instructions may include assembler instructions, instruction set architecture (ISA) instructions, machine instructions, machine dependent instructions, microcode, state-setting data, configuration data for integrated circuitry, state information that personalizes electronic circuitry and/or other structural components that are native to hardware (e.g., host processor, central processing unit/CPU, microcontroller, etc.).

In accordance with one or more embodiments, the one or more processors may be configured to receive the inspection data, store the inspection data in the one or more data stores <NUM>, <NUM>, conduct an inspection evaluation of the inspection data, and make an inspection determination of one or more of the fastener F and the inspection environment E in response to the inspection evaluation.

For example, the inspection determination may determine whether a bulb feature or retention feature of the fastener F satisfies one or more predetermined retention criteria stored in the one or more data stores <NUM>, <NUM> or the external source (e.g., computing device <NUM>, <NUM> or remote server).

In accordance with one or more embodiments, the inspection determination may determine whether the fastener F contains surface defects or internal defects based on a comparison of the fastener F and predetermined threshold criteria stored in the one or more data stores <NUM>, <NUM> or the external source (e.g., computing device <NUM>, <NUM> or remote server). For example, the inspection determination may determine whether the fastener F is damaged, or if an incorrect grip length for the fastener F was installed, or some other condition occurs that may require removal of the fastener F.

In accordance with one or more embodiments, the inspection determination may determine whether the inspection environment E contains surface defects or internal defects based on a comparison of the inspection environment E and predetermined threshold criteria stored in the one or more data stores <NUM>, <NUM> or the external source (e.g., computing device <NUM>, <NUM> or remote server).

In accordance with one or more embodiments, the inspection evaluation may comprise conducting a comparison, based on the image data from the sensor array <NUM>, <NUM>, of the fastener F and predetermined threshold image data stored in the one or more data stores <NUM>, <NUM> or the external source (e.g., computing device <NUM>, <NUM> or remote server).

In accordance with one or more embodiments, the inspection evaluation may comprise conducting a comparison, based on the image data from the sensor array <NUM>, <NUM>, of the inspection environment E and predetermined threshold image data stored in the one or more data stores <NUM>, <NUM> or the external source (e.g., computing device <NUM>, <NUM> or remote server).

In accordance with one or more embodiments, the inspection evaluation may comprise conducting a comparison, based on the measurement data from the sensor array <NUM>, <NUM>, of the fastener F with predetermined threshold measurement data stored in the one or more data stores <NUM>, <NUM> or the external source (e.g., computing device <NUM>, <NUM> or remote server).

In accordance with one or more embodiments, the inspection evaluation may comprise conducting a comparison, based on the measurement data from the sensor array <NUM>, <NUM>, of the inspection environment E with predetermined threshold measurement data stored in the one or more data stores <NUM>, <NUM> or the external source (e.g., computing device <NUM>, <NUM> or remote server).

In accordance with one or more embodiments, the inspection evaluation may comprise conducting a comparison, based on the measurement data from the sensor array <NUM>, <NUM>, of the adjacent fastening hole HA of the fastener F to be inspected with predetermined threshold measurement data stored in the one or more data stores <NUM>, <NUM> or the external source (e.g., computing device <NUM>, <NUM> or remote server). Such measurement data, for example, may be derived prior to or upon entry of the inspection apparatus <NUM>, <NUM> into the adjacent fastening hole HA.

In accordance with one or more embodiments, the inspection evaluation may comprise conducting a comparison, based on the spatial proximity data, of the fastener F and predetermined threshold spatial proximity data stored in the one or more data stores <NUM>, <NUM> or the external source (e.g., computing device <NUM>, <NUM> or remote server).

In accordance with one or more embodiments, the inspection evaluation may comprise conducting a comparison, based on the spatial proximity data, of the inspection environment E and predetermined threshold spatial proximity data stored in the one or more data stores <NUM>, <NUM> or the external source (e.g., computing device <NUM>, <NUM> or remote server).

<FIG> illustrates a flowchart of a method <NUM> of inspecting, via the inspection apparatus <NUM>, <NUM> and/or the inspection system <NUM>, a fastener installed in a fastening hole of a region of a structure that is enclosed or has limited access, in accordance with one or more embodiments.

In accordance with one or more embodiments, the method <NUM> can be implemented by the control module <NUM>, <NUM> and/or the computing device <NUM>, <NUM>. For example, the control module <NUM>, <NUM> and/or the computing device <NUM>, <NUM> can implement the method <NUM> using logic instructions (e.g., software), configurable logic, fixed-functionality hardware logic, etc., or any combination thereof. As an example, software executed on the control module <NUM>, <NUM> and/or the computing device <NUM>, <NUM> can provide functionality described or illustrated herein. In particular, software executing on the control module <NUM>, <NUM> and/or the computing device <NUM>, <NUM> can perform one or more fabrication or processing blocks of the method <NUM> set forth, described, and/or illustrated herein, or provides functionality set forth, described, and/or illustrated.

As illustrated in <FIG>, the method <NUM> can be initiated at illustrated process block <NUM>, which include positioning an inspection apparatus for entry along a longitudinal axis thereof through an adjacent fastening hole of the installed fastener to be inspected. In accordance with one or more embodiments, positioning an inspection apparatus may further comprise illuminating one or more of the installed fastener and the inspection environment external to the fastener.

The method <NUM> can then proceed to illustrated process block <NUM>, which includes detecting structural features of one or more of the fastener and an inspection environment external to the fastener as inspection data. In accordance with one or more embodiments, the inspection data comprises image data, measurement data, and position data of the installed fastener and the inspection environment.

The method <NUM> can then proceed to illustrated process block <NUM>, which includes, after detecting the structural features, conducting an inspection evaluation of the inspection data. In accordance with one or more embodiments, the inspection evaluation comprises conducting a comparison based on one or more of the image data, measurement data, and the position data, of a retention feature of the installed fastener with one or more predetermined threshold inspection data.

The method <NUM> can then proceed to illustrated process block <NUM>, which includes making an inspection determination of the installed fastener in response to the inspection evaluation. In accordance with one or more embodiments, the inspection determination comprises determining, in response to the inspection evaluation, whether the retention feature satisfies one or more predetermined retention criteria.

If "Yes," i.e., should the inspection determination conclude that the retention feature satisfies the predetermined retention criteria, the method <NUM> can then terminate or end. In which case the inspection may proceed to another installed fastener.

If "No," i.e., should the inspection determination conclude that the retention feature does not satisfy the predetermined retention criteria, the method proceeds to process block <NUM>, where an indication (e.g., one or more of an audio, a visual, or a haptic) is made flagging/identifying the fastener, structure, etc. requires rework/replacement. The method <NUM> can terminate or end after completion of illustrated process block <NUM>.

The terms "coupled," "attached," or "connected" can be used herein to refer to any type of relationship, direct or indirect, between the components in question, and can apply to electrical, mechanical, fluid, optical, electromagnetic, electromechanical or other connections. Additionally, the terms "first," "second," etc. are used herein only to facilitate discussion, and carry no particular temporal or chronological significance unless otherwise indicated. The terms "cause" or "causing" means to make, force, compel, direct, command, instruct, and/or enable an event or action to occur or at least be in a state where such event or action can occur, either in a direct or indirect manner.

Claim 1:
A method of inspecting a fastener (F) installed in a fastening hole (HF) of a region of a structure (S) that is enclosed or has limited access, the method comprising:
positioning an inspection apparatus (<NUM>) for entry along a longitudinal axis thereof through an adjacent fastening hole (HA) of the installed fastener (F) to be inspected; and
detecting structural features of one or more of the fastener (F) and an inspection environment (E) external to the fastener (F) as inspection data;
conducting an inspection evaluation of the inspection data; and
making an inspection determination of the installed fastener (F) in response to the inspection evaluation
wherein the inspection evaluation comprises conducting a comparison based on one or more of the image data, measurement data, and the position data, of a retention feature of the installed fastener with one or more predetermined threshold inspection data.