Patent Description:
An airframe defines the mechanical structure of an aircraft. Airframes are made of multiple components that provide desired structural properties. For example, a portion of an airframe for a fuselage of an aircraft may include frames, skin, and stringers that are mechanically coupled together (e.g., via co-bonding, co-curing, or fasteners) in accordance with design parameters. As presently practiced, components of an airframe are fabricated and assembled in predefined cells on a factory floor. For example, a skin of an aircraft may be assembled at one cell, and then may be transported to a new cell where frames are installed into the skin to form a full barrel section before transporting to a next cell.

While the fabrication processes discussed above are reliable, they encounter delays when work at a specific portion of a component is completed more slowly than expected. For example, if a particular portion of a fuselage section takes longer than expected for installation of frames, then the entire section remains at the cell until all of the work that has been delayed is completed. The entire production system is delayed until the full barrel section is advanced to the next cell. During these operations, heavy tooling is utilized to maintain a desired loft/contour of the component at the cell.

The abstract of <CIT> states: "A flay assembly for separating a workpiece from a manufacturing fixture has a horizontal beam assembly and a pair of vertical beam assemblies. The horizontal beam assembly includes a horizontal beam having a horizontal drive motor. Each vertical beam assembly includes a vertical beam operably engaged to the horizontal drive motor and has a workpiece attachment assembly operably engaged to a vertical drive motor. The workpiece attachment assembly has an attachment mechanism attachable to the workpiece. The horizontal drive motor and the vertical drive motors are operable in a manner to move the vertical beams away from each other along a horizontal drive axis while simultaneously moving each workpiece attachment assembly along a vertical drive axis to cause the attachment mechanisms to pull the workpiece side portions away from the manufacturing fixture while a center support of the horizontal beam maintains a workpiece crown in contact with the manufacturing fixture.

The abstract of <CIT> states: "Systems and methods are provided for enforcing contours onto parts of an aircraft. One embodiment is a method for enforcing a contour onto aircraft parts. The method includes removably attaching segmented ring details to aircraft skin details, attaching stringers to skin details to create skin assemblies, positioning skin assemblies at a support structure defining a contour, and fastening frames to the skin assemblies to create a panel. The method also includes removably installing a spreader section onto the panel to complete assembly of a brace prior to removal of the panel, transporting the panel while the brace enforces the contour, attaching the brace to braces for other panels to form a barrel section of a fuselage for an aircraft while the brace enforces the contour, and removing the brace from the barrel section after the barrel section has been formed.

The abstract of <CIT> states: "The present invention provides an apparatus and a method for producing a large-area fibre-composite structural component, in particular for the aircraft sector, comprising a predetermined shaping element, a controllable laying device for the defined laying of at least one fibrous sheet over or into the predetermined shaping element, a controllable turning device for a defined turning of the predetermined shaping element and of the laying device in relation to each other by a predetermined turning angle, and a central control device, which is connected to the laying device and the turning device for controlling of the same.

<CIT> states in its title "Spannvorrichtung zum Aufbau von aus Außenhaut und Versteifungen bestehenden schußartigen Flugzeugschalenteilen".

Embodiments described herein provide assembly line techniques and systems that facilitate contour enforcement for half barrel sections of fuselage during fabrication. Specifically, stationary arches at the assembly line contact and enforce a desired cross-sectional contour onto the half barrel sections, which facilitates the performance of work at the half barrel sections.

According to an aspect of the present disclosure, a method for assembling a section of a fuselage of an aircraft comprises:.

Advantageous, the method is one wherein enforcing the desired contour onto the half barrel section comprises extending a plurality of wheels from a first arch to enforce the inner mold line and extending a plurality of wheels from a second arch to enforce the outer mold line.

Preferably, the method is one further comprises progressing the half barrel section in a process direction through a nip to enforce contour.

Preferably, the method further comprises progressing a half barrel section in the process direction through a pre-nip prior to progressing through the nip.

Preferably, the method of further comprises determining an initial contour of the half barrel section using non-destructive inspection (NDI).

Preferably, the method is one further comprises determining an initial contour of the half barrel section using non-destructive inspection; and
setting a nip to a gap and a desired contour using the contour from the NDI, the nip defined by the plurality of wheels from a first arch extendible along the inner mold line and the plurality of wheels from a second arch extendible along the outer mold line.

Preferably, the method is one further comprises performing work on the half barrel section, within a workstation disposed along the track, while the desired contour is enforced.

Preferably, the method is one wherein performing work comprises installing a frame onto the half barrel section while the desired contour is enforced.

Preferably, the method is one wherein performing work comprises installing one or more of a door surround and a window surround while the desired contour is enforced.

Preferably, the method is one the desired contour being enforced is a cross sectional contour.

Preferably, the method is one wherein enforcing the desired contour onto the half barrel section comprises placing the wheels of the first arch into contact with the inner mold line of the half barrel section to enforce the desired contour and placing the wheels of the second arch into contact with the outer mold line of the half barrel section to enforce the desired contour.

Preferably, the method is one further comprises retracting the wheels from the half barrel section during pauses between pulses of the half barrel section.

Preferably, the method is one further comprises securing the half barrel section to the track such that a concavity of the half barrel section face a factory floor, and bearing edges of the half barrel section contact the track.

Preferably, the method is one wherein utilizing an indexing feature associated with the half barrel section to determine a desired contour comprises mating complementary features at an indexing unit with the indexing feature and operating a controller to determine the desired contour associated with the mating and based on the determining, causing a plurality of wheels to extend from a first arch to enforce the inner mold line, and a plurality of wheels to extend from a second arch to enforce the outer mold line.

According to an aspect of the present disclosure, a system for assembling a half barrel section of fuselage comprises:.

Advantageous, the system is one wherein the first component comprises a first arch further comprises wheels that extend from the first arch to enforce the desired contour upon the inner mold line and the second component comprises a second arch further comprises wheels that descend from the second arch to enforce the desired contour upon the outer mold line.

Preferably, the system is one wherein the wheels of the first arch and the wheels of the second arch oppose to form a nip, the nip operable in moving the half barrel section along the track.

Preferably, the system is one wherein the first arch is shaped substantially complementary to the inner mold line of a half barrel section and the second arch is shaped substantially complementary to the outer mold line of a half barrel section.

Preferably, the system is one wherein a first portion of the wheels are mounted circumferentially about the first arch and a second portion of the wheels are mounted circumferentially about the second arch.

Preferably, the system is one wherein the drive unit is operable to pulse the half barrel section of fuselage synchronously in a process direction along the track while holding the half barrel section such that concavities of the half barrel section face a floor of a factory, while the bearing edges of the half barrel section contact the track.

Preferably, the system is one wherein the system is operable to pulse the half barrel section while the wheels engage the half barrel section and enforce the desired contour.

Preferably, the system further comprises a plurality of stanchions, the stanchions elevating the track from a factory floor.

Preferably, the system is one wherein the track comprises a plurality of rollers, the rollers operable for movement of the half barrel section along the track.

Preferably, the system is one wherein the first arch is stationary and mounted to a factory floor and the second arch is stationary and mounted to the factory floor.

Preferably, the system is one wherein at least one of the first arch and the second arch are mobile with respect to the track.

Preferably, the system further comprises a controller, the controller programmed to control the respective extension and descending of the wheels according to a desired contour stored within the controller.

Preferably, the system further comprises a non-destructive inspection workstation operable to determine a hoopwise radius of a portion of the half barrel section during a pause between micro pulses of the half barrel section along the track.

Preferably, the system further comprises a plurality of swing arms, a first portion pivotably mounted to the first arch and a second portion pivotably mounted to the second arch and opposing the first portion and a plurality of intake rollers mounted to respective swing arms distal from the arches, the swing arms biased to form a pre-nip for the half barrel section.

Preferably, the system is one wherein biasing of the pre-nip is of sufficient force to pre-contour the half barrel section prior to engagement of the wheels.

Other illustrative embodiments (e.g., methods and computer-readable media relating to the foregoing embodiments) may be described below. 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 figures and the following description provide specific illustrative embodiments of the disclosure. It will thus be appreciated that those skilled in the art will be able to devise various arrangements that, although not explicitly described or shown herein, embody the principles of the disclosure and are included within the scope of the disclosure. Furthermore, any examples described herein are intended to aid in understanding the principles of the disclosure, and are to be construed as being without limitation to such specifically recited examples and conditions. As a result, the disclosure is not limited to the specific embodiments or examples described below, but by the claims and their equivalents.

The fuselage segments discussed herein may be fabricated as metal (e.g., aluminum) or composite parts. Composite parts, such as Carbon Fiber Reinforced Polymer (CFRP) parts, are initially laid-up in multiple layers that together are referred to as a preform. Individual fibers within each layer of the preform are aligned parallel with each other, but different layers exhibit different fiber orientations in order to increase the strength of the resulting composite part along different dimensions. The preform includes a viscous resin that solidifies in order to harden the preform into a composite part (e.g., for use in an aircraft). Carbon fiber that has been impregnated with an uncured thermoset resin or a thermoplastic resin is referred to as "prepreg. " Other types of carbon fiber include "dry fiber" which has not been impregnated with thermoset resin but may include a tackifier or binder. Dry fiber is infused with resin prior to hardening. For thermoset resins, the hardening is a one-way process referred to as curing, while for thermoplastic resins, the resin reaches a viscous form if it is re-heated, after which it can be consolidated to a desired shape and solidified. As used herein, the umbrella term for the process of transitioning a preform to a final hardened shape (i.e., transitioning a preform into a composite part) is referred to as "hardening," and this term encompasses both the curing of thermoset preforms and the forming/solidifying of thermoplastic preforms into a final desired shape.

Turning now to <FIG>, an illustration of an aircraft <NUM> is depicted in which an illustrative embodiment may be implemented. In this illustrative example, aircraft <NUM> has a right wing <NUM> and left wing <NUM> attached to fuselage <NUM>. One each of engines <NUM> is attached to right wing <NUM> and left wing <NUM>. Embodiments of aircraft are known with additional engines <NUM> and different engine placements. Fuselage <NUM> includes a tail section <NUM> and a nose section <NUM>. Horizontal stabilizer <NUM>, horizontal stabilizer <NUM>, and vertical stabilizer <NUM> are attached to tail section <NUM> of fuselage <NUM>. Aircraft <NUM> is an example of an aircraft where the majority of the fuselage <NUM> is formed from multiple half barrel sections <NUM>, the fabrication is which is partially illustrated in <FIG>. The multiple half barrel sections <NUM>, when attached together, form the majority of fuselage <NUM>.

As mentioned, fuselage <NUM> is fabricated from multiple half barrel sections <NUM>. Half barrel sections <NUM> are configured to be either an upper half barrel section <NUM> or a lower half barrel section <NUM> which are ultimately joined together to form a full barrel section <NUM>. <FIG> depicts several full barrel sections <NUM> including: <NUM>-<NUM>, <NUM>-<NUM>, <NUM>-<NUM>, <NUM>-<NUM>, and <NUM>-<NUM>. For completeness, full barrel section <NUM>-<NUM> is fabricated using upper half barrel section <NUM>-<NUM> and lower half barrel section <NUM>-<NUM>, full barrel section <NUM>-<NUM> is fabricated using upper half barrel section <NUM>-<NUM> and lower half barrel section <NUM>-<NUM>, full barrel section <NUM>-<NUM> is fabricated using upper half barrel section <NUM>-<NUM> and lower half barrel section <NUM>-<NUM>, full barrel section <NUM>-<NUM> is fabricated using upper half barrel section <NUM>-<NUM> and lower half barrel section <NUM>-<NUM>, and full barrel section <NUM>-<NUM> is fabricated using upper half barrel section <NUM>-<NUM> and lower half barrel section <NUM>-<NUM>. The full barrel section <NUM>-<NUM>, <NUM>-<NUM> corresponds to view A-A and full barrel section <NUM>-<NUM> corresponds to view B-B and are serially fastened into fuselage <NUM>. Lower half barrel section <NUM>-<NUM> is sometimes referred to as a wing box as the wings <NUM> and <NUM> attach to this section.

All of the above described half barrel sections (e.g., upper half barrel section <NUM> and lower half barrel section <NUM>), unless specifically otherwise described, will be referred to as half barrel section <NUM>. In some embodiments, the half barrel section <NUM> comprises a hardened composite skin part or a metal skin part, such as those awaiting installation of window surrounds <NUM> and door surrounds <NUM>-<NUM> (view A-A) and frames <NUM> (<FIG>) to enhance rigidity. An embodiment has one half barrel section <NUM> as a composite skin part of one aircraft model and another half barrel section <NUM> as a metal skin part progressing serially down the assembly system <NUM>.

<FIG> illustrates a side view block diagram of a fuselage assembly system <NUM> of a factory in an illustrative embodiment. Fuselage assembly system <NUM> comprises any system, device, or component operable to iteratively pulse one or more of half barrel sections <NUM> of fuselage <NUM> a distance less than their length along a track <NUM>. Fuselage assembly system <NUM> is further capable of performing work along an Inner Mold Line (IML) <NUM> and/or an Outer Mold Line (OML) <NUM> on the half barrel sections <NUM> while the half barrel sections <NUM> are paused between pulses. However, embodiments will also be described where work is performed while the half barrel section is in motion within fuselage assembly system <NUM>. Inner Mold Line (IML) <NUM> and Outer Mold Line (OML) <NUM> are also illustrated on the half barrel section <NUM> of <FIG>.

There is a section gap <NUM> between the two half barrel sections <NUM>. The section gap <NUM> can be dimensioned to provide for pauses in workstation <NUM>, <NUM>-<NUM> operation, during which worker breaks, station maintenance, and inspections can be performed. The section gap <NUM> provides these worker breaks and station maintenance benefits when section gap <NUM> is opposite workstation <NUM>, <NUM>-<NUM>. The section gap <NUM> is typically set at a multiple of the micro pulse <NUM> and/or frame pitch <NUM> (shown in <FIG>) of the half barrel sections <NUM>. The micro pulse <NUM> length is less than the length of the half barrel section <NUM> and could be as short as the frame pitch <NUM> or a fraction or multiple thereof. Therefore, the section gap <NUM> is, in one embodiment, is a multiple of frame pitch <NUM> and as illustrated, section gap <NUM> is equal to frame pitch <NUM>. Frame pitch <NUM> is generally the same as the distance between each window surround <NUM>. In one embodiment, the section gap <NUM> is between two and twenty feet. Each of the half barrel sections <NUM> defines a concavity <NUM> which encompasses one or more workstations <NUM>, <NUM>-<NUM>. Additional workstations, which provide different or the same functionalities as workstations <NUM>, <NUM>-<NUM> may also be placed within and/or external to the concavity <NUM>. End effectors <NUM> associated with the workstations <NUM>, <NUM>-<NUM> perform work on the half barrel section <NUM>. This work may comprise trimming, cutting, drilling, fastening, placing components (e.g., frames <NUM>), performing Non-Destructive Inspection (NDI) of the half barrel section <NUM>, etc..

In this embodiment, each of the half barrel sections <NUM> is moved via its bearing edge <NUM> in a process direction <NUM> (labeled "process direction <NUM>" in <FIG>) along track <NUM>. The track <NUM> comprises one or more rails <NUM>, rollers <NUM>, or other elements that facilitate motion (e.g., rolling or sliding) of the half barrel section <NUM> along the track <NUM>. Half barrel sections <NUM> are pulsed synchronously along track <NUM> in a process direction <NUM>, while a shape of the half barrel sections <NUM> is enforced (as further described herein) such that concavities <NUM> face a floor <NUM> of the factory. A half barrel section <NUM> configured as an upper half barrel section <NUM> is moved in a process direction <NUM> in a crown up position <NUM>. A half barrel section <NUM> configured as a lower half barrel section <NUM> is moved in a process direction <NUM> in a keel up position <NUM>. In further embodiments, the track <NUM> includes a drive unit <NUM> (e.g., a chain drive, motorized cart, powered rollers or other powered system) that is capable of moving the half barrel sections <NUM> in the process direction <NUM>.

In this embodiment, the track <NUM> includes stanchions <NUM> (e.g., a discretized series of stanchions), onto which rollers <NUM> are disposed. Stanchions <NUM> are separated by a stanchion gap <NUM>, which may be three feet or more, such as four to six feet. Stanchions <NUM> have a length <NUM> of more than four feet in one embodiment. Another embodiment has stanchions <NUM> of a have a length <NUM> of six or eight or more feet are also possible. The stanchion gap <NUM> and stanchion length <NUM> enables technicians to easily exit under the track <NUM> or ingress workstation <NUM>, <NUM>-<NUM> under bearing edge <NUM> of half barrel section <NUM>. In one embodiment the bearing edges <NUM> of the half barrel sections <NUM> directly contact the rollers <NUM> of the track <NUM>. The rollers <NUM> physically support the bearing edge <NUM> of the half barrel sections <NUM>, and enforce a desired Outer Mold Line (OML) <NUM> and/or Inner Mold Line (IML) <NUM> (e.g., within tolerance) onto the half barrel sections <NUM>. The track <NUM> further comprises motors <NUM> that drive the half barrel sections <NUM> (e.g., by spinning the rollers, or by pulling the half barrel sections <NUM>).

In further embodiments, the bearing edges <NUM> are mounted to rails <NUM> which ride upon the rollers <NUM>. In still further embodiments, bearing edges <NUM> are mounted upon rollers <NUM>. In an embodiment, the bearing edges <NUM> and rollers <NUM> glide along rail <NUM>. Arches <NUM>, <NUM>-<NUM> are stationary components affixed to floor <NUM>. When referred to separately, arch <NUM> will be referred to as either the second arch <NUM> or the outer arch <NUM>, and arch <NUM>-<NUM> will be referred to as the first arch <NUM>-<NUM> or the inner arch.

The arches <NUM>, <NUM>-<NUM> are systems/components that enforce an OML <NUM> and/or an IML <NUM> onto half barrel sections <NUM> while enabling the half barrel sections <NUM> to proceed through (i.e., in between them). In this embodiment, one or more second arches <NUM> contact the OML <NUM> with wheels <NUM>, while one or more inner arches <NUM>-<NUM> are disposed within concavity <NUM> contacting the IML <NUM> with wheels <NUM>-<NUM>. Enforcing the OML <NUM> and IML <NUM> comprises pushing the half barrel section <NUM> through the space between arches <NUM> and <NUM>-<NUM>. Each arch <NUM>, <NUM>-<NUM> includes a rigid fixed body <NUM>, <NUM>-<NUM>. The respective arches <NUM>, <NUM>-<NUM> includes wheels <NUM>, <NUM>-<NUM> that are mounted circumferentially around the body <NUM>, <NUM>-<NUM> and are rotatably affixed to the body <NUM>, <NUM>-<NUM>. The wheels <NUM>, <NUM>-<NUM> contact the half barrel sections <NUM> in order to physically enforce OML <NUM> and IML <NUM> (which also results in a desired contour <NUM>) onto the half barrel sections <NUM>. Wheels <NUM>, <NUM>-<NUM> also operate to push the half barrel section <NUM> along the arches <NUM>, <NUM>-<NUM>, respectively.

In further embodiments, work density, as exemplified by the number of workstations <NUM>, <NUM>-<NUM> disposed along a half barrel section <NUM>, is substantially higher than that shown in <FIG>. The number of workstations <NUM>, <NUM>-<NUM> and their complexity have been reduced and simplified for the sake of clarity. That is, the amount of work performed on the half barrel section <NUM> per square foot of factory floor space is increased as the number of workstations <NUM>, <NUM>-<NUM> per track <NUM> length is increased. The work density is also substantially higher than in prior assembly systems resulting in substantial increases in efficiency and reduced the size of assembly system <NUM>. In still further embodiments, the arches <NUM>, <NUM>-<NUM> are mobile and capable of traveling along parallel to the track <NUM>. The arches <NUM>, <NUM>-<NUM> are capable of self-propulsion or movement upon a track, which as shown in <FIG>, includes two parallel track sections <NUM>-<NUM>, <NUM>-<NUM>.

Fuselage assembly system <NUM> further comprises indexing units <NUM>. Each indexing unit <NUM> is designed to physically or communicatively couple with an indexing feature <NUM> such as an RFID chip, an added feature, such as a pin, or a machined feature, such as a hole or slot in the half barrel section <NUM>. Another embodiment has a scanner as the indexing unit <NUM> scanning the indexing feature <NUM>, particularly devices that can be scanned, like RFID chips. The indexing features <NUM> are placed at known, precise locations along the half barrel section <NUM>, and in one embodiment each of the indexing features <NUM> is separated by the same distances along the half barrel section <NUM>. In further embodiments, the indexing features <NUM> are placed at various spacings and conform to various shapes and sizes. In a further embodiment, the indexing features <NUM> are arranged linearly or are placed non-linearly, depending on the configuration of the individual sensing unit <NUM> utilized to sense a particular indexing feature <NUM>. The linear or non-linear arrangement of indexing features <NUM> include varying or non-varying spacing there between. In still further embodiments, the indexing features <NUM> are disposed in a manufacturing excess <NUM> of the half barrel section <NUM>, which is trimmed away at some point prior to completion of the half barrel section <NUM>. In such embodiments, system <NUM> is programmed to precisely stop a pulse or micropulse of the half barrel section <NUM> when the indexing feature <NUM> is within an operational field of view of a respective indexing unit <NUM>.

In other embodiments, certain of the indexing units <NUM> include a complementary feature <NUM> for insertion into, grasping, or otherwise fitting with an indexing feature <NUM> that is mechanical in nature, facilitating a hard stop when indexing feature <NUM> and complementary feature <NUM> are mated. Indexing units <NUM> are placed at fixed, known locations relative to the track <NUM> or workstation <NUM>, <NUM>-<NUM>. During assembly, half barrel section <NUM> is pulsed a distance at least equal to the shortest micro pulse <NUM>, such as a frame pitch <NUM>. That is, the half barrel section <NUM> is pulsed to an indexing unit <NUM>. Whenever the indexing features <NUM> in the half barrel section <NUM> and the complementary features <NUM> in the indexing units <NUM> are mated, the location of the half barrel section <NUM> is indexed to a known location in a coordinate space shared by the track <NUM>, the indexing units <NUM>, and/or workstations <NUM>, <NUM>-<NUM> and the concavity <NUM>. Specifically, each indexing unit <NUM> is disposed at a known offset (e.g., along three axes) from a workstation <NUM>, <NUM>-<NUM>. This means that the act of indexing a half barrel section <NUM> to the indexing units <NUM> causes the position of the half barrel section <NUM> OML <NUM> and/or IML <NUM> within the purview <NUM>, <NUM>-<NUM>, <NUM>-<NUM> of each of the workstations <NUM>, <NUM>-<NUM> and/or arch <NUM>, <NUM>-<NUM> to be known to the workstation <NUM>, <NUM>-<NUM> or arch <NUM>, <NUM>-<NUM> at the end of each micro pulse <NUM>. Furthermore, the act of indexing a half barrel section <NUM> to the indexing units <NUM> causes the position of the half barrel section <NUM> OML <NUM> and/or IML <NUM> within the purview <NUM>, <NUM>-<NUM>, <NUM>-<NUM> of each of the arches <NUM>, <NUM>-<NUM> to be known at the end of each micro pulse <NUM>. Arches <NUM>, <NUM>-<NUM> enforce a desired OML <NUM> and/or IML <NUM> for the half barrel sections <NUM> and bring about a contour <NUM> (shown in <FIG>) at the arch <NUM>, <NUM>-<NUM> and/or workstation <NUM>, <NUM>-<NUM> while indexing occurs and may continue to do so before and/or after indexing.

Indexing conveys to the arches <NUM>, <NUM>-<NUM> specifics on the half barrel section <NUM> within the purview <NUM>-<NUM>, <NUM>-<NUM> of arches <NUM>, <NUM>-<NUM>, respectively. The information is used to set the position of the wheels <NUM>, <NUM>-<NUM> relative to the arch <NUM>, <NUM>-<NUM> using connectors <NUM>, <NUM> and connectors <NUM>-<NUM>, <NUM>-<NUM>, respectively. The radius <NUM> (shown in <FIG>) of the half barrel sections <NUM> may vary from one half barrel section <NUM> to the next. In an embodiment, half barrel section <NUM> is one model with a specific radius <NUM> and the next half barrel section <NUM> will require a different radius <NUM>. Another embodiment includes the half barrel sections <NUM> that have a non-constant or tapered radius <NUM> as the half barrel section <NUM> micro pulses <NUM> in process direction <NUM>. A non-constant or tapered half barrel section <NUM> will have a radius <NUM> and a second radius <NUM>-<NUM> which are not equal. The desired contour <NUM> of half barrel sections <NUM> is conveyed from the indexing feature <NUM> to the arch <NUM>, <NUM>-<NUM> via complementary feature <NUM> and indexing unit <NUM>. The wheels <NUM>, <NUM>-<NUM> are adjusted relative to arches <NUM>, <NUM>-<NUM> to suit radius <NUM> of the half barrel section <NUM>, respectively. Variations from model to model include different size radius <NUM> of the half barrel section <NUM>. The wheels <NUM>, <NUM>-<NUM> are positioned relative to the arch <NUM>, <NUM>-<NUM> such that contour <NUM> can be enforced upon half barrel section <NUM> within the purview <NUM>-<NUM>, <NUM>-<NUM> of arches <NUM>, <NUM>-<NUM>, respectively, for a particular radius <NUM>. The leading edge <NUM> of half barrel section <NUM> is engaged by wheels <NUM>, <NUM>-<NUM> during micro pulse <NUM>. The wheels <NUM>, <NUM>-<NUM> enforce the contour <NUM> upon half barrel section <NUM> until the trailing edge passes through the wheels <NUM>, <NUM>-<NUM>.

Purview <NUM>-<NUM>, <NUM>-<NUM> is the width of the work performed by arches <NUM>, <NUM>-<NUM> upon half barrel section <NUM> during a pause or during a pulse. Stated differently, purview <NUM>-<NUM>, <NUM>-<NUM> is the length of the half barrel section <NUM> that is within the working reach of the arches <NUM>, <NUM>-<NUM> during a pause or during a micro pulse <NUM>. The arches <NUM>, <NUM>-<NUM> are illustrated with a greater purview <NUM>-<NUM>, <NUM>-<NUM> relative to the lengthwise portion <NUM> than in actual practice. The purview <NUM>-<NUM>, <NUM>-<NUM> of the arches <NUM>, <NUM>-<NUM> is typically closer in length to micro pulse <NUM> length. The purview <NUM>-<NUM>, <NUM>-<NUM> of arches <NUM>, <NUM>-<NUM> may or may not overlap.

As will be readily understood, only a small lengthwise portion of the half barrel section <NUM> is engaged by arches <NUM>, <NUM>-<NUM>, and wheels <NUM>, <NUM>-<NUM> at any one time, described in the preceding paragraph as purview <NUM>-<NUM> and <NUM>-<NUM>. The influence of the arches <NUM>, <NUM>-<NUM> on the half barrel section <NUM> will be felt in the half barrel section <NUM> both upstream and downstream of the arches <NUM>, <NUM>-<NUM>. So in certain implementations a piecewise portion <NUM>, longer than purview <NUM>-<NUM> or purview <NUM>-<NUM>, of the half barrel section <NUM> is held in the desired contour <NUM>. The addition of the frames <NUM> and surrounds <NUM>, <NUM>-<NUM> also operate to enforce the desired contour <NUM> downstream of the arches <NUM>, <NUM>-<NUM>. As an example, and for illustration only, the arches <NUM>, <NUM>-<NUM> operate to enforce a desired contour <NUM> for the length of one or two frame pitches <NUM> on each side of the arches <NUM>, <NUM>-<NUM>.

In one embodiment, indexing is performed at least according to the following description. A structure in the form of a half barrel section <NUM> is carried on the bearing edge <NUM> upon a track <NUM> comprising a set of stanchions <NUM> (e.g., pogos) affixed to the floor <NUM>. The half barrel section <NUM> was fabricated on a layup mandrel according to precise dimensions. This precise layup enables indexing features <NUM> to be precisely located in a manufacturing excess <NUM> of the half barrel section <NUM>. Thus, once the half barrel section <NUM> is precisely located on the stanchions <NUM>, the arches <NUM>, <NUM>-<NUM> enforce the OML <NUM> and/or IML <NUM> of the half barrel section <NUM>. The OML <NUM> and/or IML <NUM> is precisely known when the indexing feature <NUM> is engaged, without the need for a full scan via probes or optical technology at each workstation <NUM>, <NUM>-<NUM> after each micro pulse <NUM>.

The relative stiffness of the de-molded or otherwise formed half barrel section <NUM> is relied upon to help the half barrel section <NUM> maintain a configuration reasonably close to a desired OML <NUM> and/or IML <NUM> (e.g., desired contour <NUM>) and without the need for any shape defining tooling to be mounted or affixed to the half barrel section <NUM> during the micro pulse149. Shape defining tooling would require an additional workstation (e.g., similar to workstation <NUM>) for its installation upon half barrel section <NUM> and another additional workstation for removal of the shape defining tooling. In the example, instances of the shape defining tooling would be mounted upon the ends of the half barrel section <NUM> and one or more additional instances would be mounted somewhere in between the ends. The shape defining tools would somewhat obscure access to the half barrel section <NUM> until it is removed. Further, the addition and removal of shape defining tooling can be looked upon as non-value added work with respect to the half barrel section <NUM>.

In the embodiments disclosed herein, the indexing features <NUM> are located precisely into the half barrel section <NUM> relative to the OML <NUM> and/or IML <NUM> of the half barrel section <NUM> and the precisely located rails features of track <NUM> (e.g., rails <NUM> and rollers <NUM>) and arches <NUM>, <NUM>-<NUM> help convey the half barrel section <NUM> from workstation <NUM> to workstation <NUM>-<NUM> without distortion. Therefore, a 3D position and orientation, like OML <NUM> and/or IML <NUM> of the half barrel section <NUM> is known quickly and precisely when indexed after each micro pulse <NUM> without the need to re-scan and adjust the half barrel section <NUM> after each movement.

Continuing, the frames <NUM>, window surrounds <NUM> and door surrounds <NUM>-<NUM> are installed into half barrel section <NUM> to stiffen it prior to removing window and/or door installation manufacturing excess <NUM> resulting in trimmed edge <NUM>-<NUM>. In the illustrated example, workstation <NUM> installs frames <NUM> into half barrel section <NUM>. Workstation <NUM>-<NUM> fastens window surrounds <NUM> into half barrel section <NUM>. The traveling workstation <NUM>-<NUM> is attached at placement point <NUM>-<NUM> and rides along with half barrel section <NUM> while performing work during micro pulses <NUM> and/or pauses between micro pulses <NUM>. The traveling workstation <NUM>-<NUM> rides along and separates manufacturing excess <NUM> from half barrel section <NUM> after window surrounds <NUM>, door surrounds <NUM>-<NUM>, and frames <NUM> are installed.

Other embodiments of workstations <NUM> are illustrated in <FIG>. Specifically, traveling workstation <NUM>-<NUM> and traveling workstation <NUM>-<NUM> include flex track type fastener installation apparatus shown in <FIG>. The traveling workstation <NUM>-<NUM> travels along with the half barrel section <NUM> like a "hitch hiker" and then returns to a placement point <NUM>-<NUM> for reattachment and further work on half barrel section <NUM>. An embodiment may have multiple traveling workstations <NUM>-<NUM> travelling along with half barrel section <NUM> at any one time. Furthermore, prior to having the windows or doors manufacturing excess <NUM> removed, the frames <NUM> and window surround <NUM> and door surrounds <NUM>-<NUM> are added to stiffen the half barrel section <NUM> and then windows and/or doors manufacturing excess <NUM> is removed. While only workstations <NUM>, <NUM>-<NUM> are shown, many more workstations are possible.

Because of the precise indexing performed, the technicians at each workstation <NUM>, <NUM>-<NUM> are able to know exactly where they are or tooling, like end effectors <NUM>, are located relative to the half barrel section <NUM>. The half barrel section <NUM> is mechanically or otherwise held in place during indexing. The OML <NUM> or IML <NUM> of the half barrel section <NUM> is then established or indexed into any Numerical Control (NC) programming or automated system in use at the workstation <NUM>, <NUM>-<NUM>. Therefore, no setup time or scanning is needed after each pulse of the half barrel section <NUM>. Furthermore, structure added to (e.g., frames <NUM>, surrounds <NUM>) or removed (manufacturing excess <NUM>) from the half barrel section <NUM> in the prior workstations <NUM>, <NUM>-<NUM> may be added to whatever half barrel section <NUM> model or representation is within the system <NUM>, without the need to scan the half barrel section <NUM> for the changes.

That is, the indexing of a half barrel section <NUM> may be performed by aligning the half barrel section <NUM> to the indexing unit <NUM>. The workstations <NUM>, <NUM>-<NUM> have a known relationship with the indexing unit <NUM>, so this also indexes the half barrel section <NUM> to the workstations <NUM>, <NUM>-<NUM>. When the two are in a known relationship, tools, such as end effector <NUM>, at the workstations <NUM>, <NUM>-<NUM> are in a known relationship to the OML <NUM> and IML <NUM> of the half barrel section <NUM>. Thus, indexing a half barrel section <NUM> may include mating the indexing feature <NUM> at a half barrel section <NUM> with a complementary feature <NUM> at an indexing unit <NUM> having a known physical offset from the workstations <NUM>, <NUM>-<NUM>. This is because the complementary features <NUM> at the indexing unit <NUM> are pre-located and sized to fit with the indexing features <NUM> while the half barrel section <NUM> is at a specific and precisely determined location.

In an embodiment, mating the complementary features <NUM> at the indexing unit <NUM> with the indexing features <NUM> conveys the type of half barrel section <NUM> and the extent of the work to be performed upon half barrel section <NUM> within the purview <NUM> of workstation <NUM>, <NUM>-<NUM>, <NUM>-<NUM>. Purview <NUM> is the width of the work performed by a workstation <NUM>, <NUM>-<NUM> upon half barrel section <NUM>. The purview <NUM> runs in the lengthwise portion <NUM> of the half barrel section <NUM>. The type of half barrel section <NUM> conveys to workstations <NUM>, <NUM>-<NUM>, <NUM>-<NUM> what feeder lines <NUM>-<NUM>, <NUM>-<NUM> need to provide just-in-time (JIT) to workstations <NUM>, <NUM>-<NUM>, respectively. The feeder line <NUM>-<NUM> provides frames <NUM>, fasteners, sealant and etc. to workstation <NUM> JIT. The feeder line <NUM>-<NUM> provides window surrounds <NUM>, fasteners, sealant and etc. to workstation <NUM>-<NUM> JIT.

In another embodiment, mating the complementary features <NUM> at the indexing unit <NUM> with the indexing features <NUM> conveys OML <NUM> and IML <NUM> data to arches <NUM>, <NUM>-<NUM>. This information is used to help the arches <NUM>, <NUM>-<NUM> enforce the desired OML <NUM> and/or IML <NUM> upon half barrel section <NUM> using wheels <NUM>. Arches <NUM>, <NUM>-<NUM> can be an adjunct upon workstations <NUM>, <NUM>-<NUM> in addition to being a standalone. Generally speaking, arches <NUM>, <NUM>-<NUM> are no longer needed after installation of frames <NUM>, window surrounds <NUM> and door surrounds <NUM>-<NUM> as these also operate to enforce the OML <NUM> and IML <NUM> on the half barrel sections <NUM>.

The operations of the track <NUM>, workstations <NUM>, <NUM>-<NUM>, arches <NUM>, <NUM>-<NUM> and/or other components are managed by controller <NUM>. In one embodiment, controller <NUM> determines a progress of the half barrel section <NUM> along the track <NUM> (e.g., based on input from a technician or through the automated sensing of indexing features <NUM>), in accordance with an automated process such as input from a camera or physical sensor, such as a linear or rotary actuator. Based upon index conveyed information to arches <NUM>, <NUM>-<NUM>, the controller <NUM> instructs the connectors <NUM>, <NUM>-<NUM>, <NUM>, <NUM>-<NUM> to reach length <NUM>, <NUM>-<NUM> (shown in <FIG>). Referring to <FIG> the controller <NUM> positions the wheels <NUM>, <NUM>-<NUM> to form a nip <NUM> at the desired radius <NUM>. Preliminarily, nip <NUM> is set at gap <NUM>-<NUM> to facilitate leading edge <NUM> initially passing between wheels <NUM>, <NUM>-<NUM>. Then controller <NUM> instructs the connectors <NUM>, <NUM>-<NUM>, <NUM>, <NUM>-<NUM> to form nip <NUM> at gap <NUM>. The controller <NUM> uses this input to manage the operations of the various components in accordance with instructions stored in a Numerical Control (NC) program. Controller <NUM> may be implemented, for example, as custom circuitry, as a hardware processor executing programmed instructions, or some combination thereof.

This process, using the arches <NUM>, <NUM>-<NUM>, is used to enforce a contour <NUM> onto the half barrel section <NUM> within the purview <NUM> of an adjacent workstation <NUM>, <NUM>-<NUM> during the micro pulse <NUM> or pause between micro pulses <NUM>. This permits a forcing of half barrel section <NUM> into contour <NUM> transiently within workstation <NUM>, <NUM>-<NUM> when contour <NUM> is out of tolerance.

Illustrative details of the operation of fuselage assembly system <NUM> will be discussed with regard to <FIG>. Assume, for this embodiment, that half barrel section <NUM> of fuselage (e.g., half barrel sections, one-third barrel sections, or any suitable circumferential fraction) have had bearing edges <NUM> trimmed into them on a layup mandrel prior to demolding. The sections have been demolded and await assembly work such as trimming, frame installation, inspection, or other activities.

<FIG> is a flowchart illustrating a method of operating a fuselage assembly system <NUM> in an illustrative embodiment. The steps of method <NUM> are described with reference to fuselage assembly system <NUM> of <FIG>, but those skilled in the art will appreciate that method <NUM> may be performed in other systems. The steps of the flowcharts described herein are not all inclusive and may include other steps not shown. The steps described herein may also be performed in an alternative order.

In step <NUM>, half barrel sections <NUM> of fuselage are secured to the track <NUM> such that concavities <NUM> of the half barrel sections <NUM> face the floor <NUM>, and bearing edges <NUM> of the half barrel sections <NUM> directly contact the track <NUM>. For upper half barrel sections <NUM>, the half barrel sections <NUM> are moved in a process direction <NUM> in a crown up position <NUM>. For lower half barrel sections <NUM>, the half barrel sections <NUM> are moved in a process direction <NUM> in a keel up position <NUM>. Phrased another way, the half barrel sections <NUM> form half-cylinder or an upside-down "U" shape with the keel at the apex of the "U" shape. At each apex end of the upside-down "U" and concavity <NUM> up, a bearing edge <NUM> is held/supported by rollers <NUM> of the track <NUM>, and directly contacts these rollers <NUM>. In one embodiment, securing the half barrel sections <NUM> to the track <NUM> comprises placing the half barrel sections <NUM> onto the track <NUM> such that the bearing edges <NUM> are held in place by the rollers <NUM>.

In step <NUM>, the half barrel sections <NUM> are pulsed (e.g., synchronously) along the track <NUM> in a process direction <NUM>. In one embodiment, pulsing the half barrel sections <NUM> comprises micro pulsing the half barrel sections <NUM> by a distance less than the length of a half barrel section <NUM>. In a further embodiment, the half barrel sections <NUM> are micro pulsed by a frame pitch <NUM> (i.e., a distance between frames <NUM> that will be placed into a half barrel section <NUM>), although any suitable pulse distance may be utilized including multiples or fractions of frame pitch <NUM>. During pulses, the half barrel sections <NUM> may roll across wheels <NUM>, <NUM>-<NUM> mounted to the arches <NUM>, <NUM>-<NUM>, and these wheels <NUM>, <NUM>-<NUM> may contact the half barrels sections <NUM> during and/or after movement of the half barrel sections <NUM> to enforce the desired contour <NUM>.

However, pulses less than a length of a half barrel section <NUM> are also referred to as "micro pulses. " As used herein, a micro pulse may be any suitable distance including multiples of frame pitch <NUM>. In one embodiment, a gap of at least two feet is left between the half barrel sections <NUM> during the pulsing. This enables technicians to exit between the half barrel sections <NUM> when the section gap <NUM> coincides with the workstations <NUM>, <NUM>-<NUM>. In further embodiments, the stanchions <NUM> are tall enough for the technicians to walk or duck underneath the track <NUM>.

In step <NUM>, arches <NUM>, <NUM>-<NUM>, which define a cross-sectional OML <NUM> and IML <NUM>, enforce the cross-sectional OML <NUM> and IML <NUM> onto the half barrel sections <NUM>. Enforcing includes pushing the half barrel section <NUM> into contour <NUM>. In this embodiment, because wheels <NUM>, <NUM>-<NUM> are in a known position with respect to the bodies <NUM> of the arches <NUM>, <NUM>-<NUM>, and because wheels <NUM>, <NUM>-<NUM> contact the half barrel sections <NUM>, the wheels <NUM>, <NUM>-<NUM> hold the half barrel sections <NUM> in position and physically enforce conformance with a desired OML <NUM> and IML <NUM>. In further embodiments, wheels <NUM>, <NUM>-<NUM> only contact the half barrel sections <NUM> if the half barrel sections <NUM> are out of contour <NUM>, and are used to enforce OML <NUM> and IML <NUM> onto the half barrel sections <NUM>. In still further embodiments, the wheels <NUM>, <NUM>-<NUM> maintain contact with the half barrel sections <NUM> between micro pulses, or are retracted from the half barrel sections <NUM> via connectors <NUM>, <NUM>-<NUM>, <NUM>, and <NUM>-<NUM>. The connectors <NUM>, <NUM> and <NUM>-<NUM>, <NUM>-<NUM> extendably attach the wheels <NUM>-<NUM>, <NUM> to arch <NUM> and arch <NUM>-<NUM>, respectively.

In step <NUM>, work is performed on the half barrel sections <NUM> while the cross-sectional OML <NUM> and IML <NUM> is enforced. In embodiments where the half barrel sections <NUM> are pulsed, the work is performed during pauses between micro pulses <NUM>, while wheels <NUM>, <NUM>-<NUM> of the arches <NUM>, <NUM>-<NUM> are forced into contact with the half barrel sections <NUM>. In embodiments where the half barrel sections <NUM> are continuously moved, the work is performed as the half barrel sections <NUM> proceed in the process direction <NUM>. The work is performed by workstations <NUM>, <NUM>-<NUM> via end effectors <NUM>, and may comprise cutting, drilling, trimming (e.g., final edge trimming). Another embodiment has tooling devices (e.g., those associated with traveling workstation <NUM>-<NUM>, for example) attached to the half barrel section <NUM> to perform work upon the half barrel section <NUM> as it continues in the process direction <NUM>. The tooling device, not shown, separates from the half barrel section <NUM> when work is completed and the tool returns to attachment point <NUM>-<NUM> in the continuously moved line as described above. Such tooling might include, for example, Non-Destructive Inspection (NDI) devices, placing, fastening, etc. as discussed above. In embodiments where the half barrel sections <NUM> are micro pulsed <NUM>, after the pause is completed, work proceeds to step <NUM> and the half barrel sections <NUM> are micro pulsed <NUM> again to receive additional work.

Method <NUM> provides a technical benefit by directly enforcing a contour <NUM> onto large moving parts, such as half barrel sections <NUM>, without requiring the attachment of a jig or other component to those parts. Attaching a jig to enforce OML <NUM> and IML <NUM> is a non-value added task which adds effort and time to the manufacturing process. The arches <NUM>, <NUM>-<NUM> and wheels <NUM>, <NUM>-<NUM> provide flexibility to the fabrication process as OML <NUM> and IML <NUM> are enforced without restricting access to the portion of the half barrel section <NUM> within the purview of workstation <NUM>, <NUM>-<NUM>. Therefore, there is no ride along contouring tooling to further restrict access to the half barrel section <NUM> as it progresses through workstations <NUM>, <NUM>-<NUM>. This enables work to be performed precisely and without access encumbrances as the half barrel section <NUM> micro pulses <NUM> through workstations <NUM>, <NUM>-<NUM>. Furthermore, because multiple workstations <NUM>, <NUM>-<NUM> can be disposed within a concavity <NUM> of a half barrel section <NUM>, a large number of types of work (e.g., drilling, trimming, sealing, painting, inspection, etc.) can be performed simultaneously across various portions of the half barrel section <NUM> within the purview of workstations <NUM>, <NUM>-<NUM>. This increases assembly speed as well as work density on the factory floor <NUM>. Still further, method <NUM> enables transport time for a half barrel section <NUM> to be transformed into value-added time wherein work is performed on the half barrel section <NUM>, particularly during NDI inspection or trimming to remove manufacturing excess <NUM>, <NUM> and/or bearing edge <NUM>.

Purview <NUM> is the width of the work performed by a workstation <NUM>, <NUM>-<NUM> upon half barrel section <NUM> during a pause or during a pulse. Stated differently, purview <NUM> is the length of the half barrel section <NUM> that is within the working reach of the workstation <NUM>, <NUM>-<NUM> during a pause or during a pulse. The workstations <NUM>, <NUM>-<NUM> are illustrated with a greater purview <NUM> relative to the lengthwise portion <NUM> than in actual practice. The purview <NUM> of the workstations <NUM>, <NUM>-<NUM> is typically closer in length to micro pulse <NUM> length. The purview <NUM> of workstations <NUM>, <NUM>-<NUM> do not overlap.

<FIG> is a flowchart illustrating a method of operating a fuselage assembly system <NUM> in an illustrative embodiment. The steps of method <NUM> are described with reference to fuselage assembly system <NUM> of <FIG> and <FIG> through <FIG>, but those skilled in the art will appreciate that method <NUM> may be performed in other systems. The steps of the flowcharts described herein are not all inclusive and may include other steps not shown. The steps described herein may also be performed in an alternative order.

The half barrel sections <NUM> of fuselage are secured to the track <NUM> such that concavities <NUM> of the half barrel sections <NUM> face the floor <NUM>, and bearing edges <NUM> of the half barrel sections <NUM> directly contact the track <NUM>. Half barrel sections <NUM> for upper half barrel sections <NUM> are moved in a process direction <NUM> in a crown up position <NUM>. Each indexing unit <NUM> is designed to physically or communicatively couple with an indexing feature <NUM> such as an RFID chip, an added feature, such as a pin, or a machined feature, such as a hole or slot in the half barrel section <NUM>. Another embodiment has a scanner as the indexing unit <NUM> scanning the indexing feature <NUM>, particularly scanable devices like RFID chips, to control the movement of the half barrel section <NUM> via input into controller <NUM>, which in turns controls operation of drive unit <NUM>. Each of the indexing units <NUM> includes a complementary feature <NUM> for insertion into, grasping, or otherwise fitting with an indexing feature <NUM> facilitating a hard stop when mated.

Indexing is performed at least according to the following description. The half barrel section <NUM> is carried on the bearing edge <NUM> upon a track <NUM> comprising a set of stanchions <NUM> (e.g., pogos) affixed to the floor <NUM>. The half barrel section <NUM> was fabricated on a layup mandrel according to precise dimensions. This precise layup enables indexing features <NUM> to be precisely located in a manufacturing excess <NUM> of the half barrel section <NUM>.

The half barrel section <NUM> is indexed to a workstation (similar to workstations <NUM>) configured as NDI stations <NUM>, <NUM>-<NUM> (shown in <FIG>) in step <NUM>. Within the purview <NUM>-<NUM> of NDI station <NUM>, <NUM>-<NUM>, the radius <NUM>-<NUM> (shown in <FIG>) of the half barrel section <NUM> is measured hoopwise <NUM> while micro pulsing through the NDI station <NUM>, <NUM>-<NUM> in step <NUM>. Conveying the NDI station <NUM>, <NUM>-<NUM> information, regarding radius <NUM>-<NUM> for use in creating contour <NUM>, through controller <NUM> to arches <NUM>, <NUM>-<NUM> for use within the purview <NUM>-<NUM>, <NUM>-<NUM> of the arches <NUM>, <NUM>-<NUM> is in step <NUM>. Indexing the half barrel section <NUM> to the arches <NUM>, <NUM>-<NUM> is completed in step <NUM>. Positioning of wheels <NUM>, <NUM>-<NUM> relative to arches <NUM>, <NUM>-<NUM> to form a nip <NUM> preliminarily set at gap <NUM>-<NUM> and a radius <NUM>-<NUM> is performed in step <NUM>. Micro pulsing a leading edge <NUM> through nip <NUM> is illustrated by step <NUM>. The nip <NUM> is set at a gap <NUM> to enforce a contour <NUM> upon half barrel section <NUM> in step <NUM>. Enforcing a contour <NUM> onto the half barrel section <NUM> within the purview <NUM>-<NUM>, <NUM>-<NUM> of arches <NUM>, <NUM>-<NUM> while micro pulsing the half barrel section <NUM> through the nip <NUM> using measured data for the same half barrel section <NUM> when within the purview <NUM>-<NUM> of NDI station <NUM>, <NUM>-<NUM> I is illustrated in step <NUM>. Purview <NUM>-<NUM> is the width of the work performed by the NDI station <NUM>, <NUM>-<NUM> upon half barrel section <NUM> during a pause or during a pulse between pauses.

<FIG> is a flowchart illustrating a method <NUM> of operating a fuselage assembly system <NUM> in an illustrative embodiment. The steps of method <NUM> are described with reference to fuselage assembly system <NUM> of <FIG> and <FIG> through <FIG>, but those skilled in the art will appreciate that method <NUM> may be performed in other systems. The steps of the flowcharts described herein are not all inclusive and may include other steps not shown. The steps described herein may also be performed in an alternative order.

The half barrel section <NUM> is micro pulsed <NUM> into a placement point <NUM>-<NUM> in step <NUM>. Workstation <NUM>, <NUM>-<NUM> installs frames <NUM> into half barrel section <NUM>. Workstation <NUM>-<NUM> fastens window surrounds <NUM> into half barrel section <NUM>.

The traveling workstation <NUM>-<NUM> is coupled at placement point <NUM>-<NUM> and rides along with half barrel section <NUM> while performing work during micro pulses <NUM> and/or pauses between micro pulses <NUM> in step <NUM>. The traveling workstation <NUM>-<NUM> rides along and separates manufacturing excess <NUM> from half barrel section <NUM> after window surrounds <NUM> and frames <NUM> are installed. Another embodiment has workstation <NUM>, <NUM>-<NUM> locating frames and/or window surrounds onto half barrel section <NUM>. Then the traveling workstation <NUM>-<NUM> and traveling workstation <NUM>-<NUM> are coupled to half barrel section <NUM> also as part of step <NUM>.

The workstations <NUM>, <NUM>-<NUM> temporarily fasten the frame <NUM>, window surround <NUM> and/or door surround <NUM>-<NUM> to half barrel section <NUM>. An embodiment of temporarily fasten includes intermittent installation of final fasteners within workstation <NUM>, <NUM>-<NUM> to tack the frame <NUM>, window surround <NUM> and/or door surround <NUM>-<NUM> into place. Intermittent fastening includes fastening at every <NUM>th or <NUM>th fastener or some other type of spacing and using production type fasteners. Another embodiment of temporarily fasten includes intermittent installation of temporary fasteners within workstation <NUM>, <NUM>-<NUM> to tack the frame <NUM>, window surround <NUM> and/or door surround <NUM>-<NUM> into place. Intermittent fastening includes fastening at every <NUM>th or <NUM>th fastener or some other type of spacing and using cleco type fasteners. The traveling workstation <NUM>-<NUM> and traveling workstation <NUM>-<NUM> include flex track type fastener installation apparatus shown in <FIG>. The traveling workstation <NUM>-<NUM> and traveling workstation <NUM>-<NUM> vacuum attach to half barrel section <NUM> and fasten frames <NUM> and/or window surrounds <NUM> and/or door surrounds <NUM>-<NUM> to half barrel section <NUM>. The traveling workstation <NUM>-<NUM> and traveling workstation <NUM>-<NUM> travel along with the half barrel section <NUM> as it micro pulses <NUM> and/or pauses and even includes possibly passing through workstations <NUM>, <NUM>-<NUM> while performing fastener installation as part of step <NUM>. The traveling workstation <NUM>-<NUM> travels along with the half barrel section <NUM> like a "hitch hiker" and separates manufacturing excess <NUM> from half barrel section <NUM> also part of step <NUM>.

The traveling workstation <NUM>-<NUM>, traveling workstation <NUM>-<NUM> and traveling workstation <NUM>-<NUM> decouple from half barrel section <NUM> after fastener installation or trimming is completed as part of step <NUM>. The traveling workstation <NUM>-<NUM>, traveling workstation <NUM>-<NUM> and traveling workstation <NUM>-<NUM> then return to a placement point <NUM>-<NUM>, <NUM>-<NUM> (shown in <FIG>), respectively. An embodiment has the traveling workstation <NUM>-<NUM>, traveling workstation <NUM>-<NUM> and traveling workstation <NUM>-<NUM> traveling back to the placement point <NUM>-<NUM>, <NUM>-<NUM> on their own power with an onboard crawler configuration.

Referring now to <FIG>, retractable wheels (not shown) are arrayed along the first flexible rail <NUM>, <NUM>-<NUM>, <NUM>-<NUM> and the second flexible rail <NUM>, <NUM>-<NUM>, <NUM>-<NUM> and the carrier <NUM>, <NUM>-<NUM>, <NUM>-<NUM>. When in crawler configuration, traveling workstation <NUM>-<NUM>, traveling workstation <NUM>-<NUM> and traveling workstation <NUM>-<NUM> travel on their own power from the coupled point on half barrel section <NUM> to another couple point on half barrel section <NUM> and then recouple. Another configuration has <NUM>-<NUM>, traveling workstation <NUM>-<NUM> and traveling workstation <NUM>-<NUM> travel on their own power back to placement point <NUM>-<NUM>, <NUM>-<NUM> as part of step <NUM>. An embodiment may have multiple traveling workstations <NUM>-<NUM>, <NUM>-<NUM>, and <NUM>-<NUM> travelling along with half barrel section <NUM> at any one time.

Furthermore, prior to having the windows or doors manufacturing excess <NUM> removed, the frames <NUM> and window surround <NUM> and door surrounds <NUM>-<NUM> are added to stiffen the half barrel section <NUM> and then windows or doors manufacturing excess <NUM> is removed.

<FIG> is a flowchart illustrating a method of operating a fuselage assembly system <NUM> in an illustrative embodiment. The steps of method <NUM> are described with reference to fuselage assembly system <NUM> of <FIG> and <FIG>, <FIG>, but those skilled in the art will appreciate that method <NUM> may be performed in other systems. The steps of the flowcharts described herein are not all inclusive and may include other steps not shown. The steps described herein may also be performed in an alternative order.

Micro pulse <NUM> the half barrel section <NUM> into workstation <NUM>, <NUM>-<NUM> in step <NUM>. The half barrel section <NUM> is indexed to the workstation <NUM>, <NUM>-<NUM> during the micro pulse <NUM> in step <NUM>. The workstations <NUM>, <NUM>-<NUM> locate frames <NUM>, window surrounds <NUM> and/or door surround <NUM>-<NUM> onto half barrel section <NUM> as part of step <NUM>. Then the workstations <NUM>, <NUM>-<NUM> temporarily fasten frames <NUM>, window surrounds <NUM> and/or door surround <NUM>-<NUM> to half barrel section <NUM> as part of step <NUM>. An embodiment of temporarily fasten includes intermittent installation of final fasteners within workstation <NUM>, <NUM>-<NUM> to tack the frame <NUM>, window surround <NUM>, door surround <NUM>-<NUM> into place. Intermittent fastening includes fastening at every <NUM>th or <NUM>th fastener of some other type of spacing and using production type fasteners. Another embodiment of temporarily fastening includes intermittent installation of temporary fasteners within workstation <NUM>, <NUM>-<NUM> to tack the frame <NUM>, window surround <NUM>, and/or door surround <NUM>-<NUM> into place. Intermittent fastening includes fastening at every <NUM>th or <NUM> fastener of some other type of spacing and using cleco type fasteners. Then the traveling workstation <NUM>-<NUM> and traveling workstation <NUM>-<NUM> are coupled to half barrel section <NUM>. The traveling workstation <NUM>-<NUM> and traveling workstation <NUM>-<NUM> fastens the frames <NUM>, window surrounds <NUM> and/or door surround <NUM>-<NUM> to half barrel section <NUM> as the half barrel section <NUM> progresses through at least one micro pulse <NUM> as part of step <NUM>.

The workstation <NUM>, <NUM>-<NUM> temporarily fastens the frame <NUM>, window surround <NUM>, or door surround <NUM>-<NUM> to half barrel section <NUM>. The traveling workstation <NUM>-<NUM> and traveling workstation <NUM>-<NUM> include flex track type fastener installation apparatus shown in <FIG>. The traveling workstations <NUM>-<NUM>, <NUM>-<NUM> and <NUM>-<NUM> vacuum attach to half barrel section <NUM> and fasten frames <NUM> and/or window surrounds <NUM> and/or door surrounds <NUM>-<NUM> to half barrel section <NUM>. The traveling workstations <NUM>-<NUM>, <NUM>-<NUM> and <NUM>-<NUM> travel along with the half barrel section <NUM> as it micro pulses <NUM> and/or pauses and even includes possibly passing through workstations <NUM>, <NUM>-<NUM> while performing fastener installation as part of step <NUM>. The traveling workstation <NUM>-<NUM> travels along with the half barrel section <NUM> like a "hitch hiker" and separates manufacturing excess <NUM> from half barrel section <NUM> also part of step <NUM>.

The traveling workstation <NUM>-<NUM>, traveling workstation <NUM>-<NUM> and traveling workstation <NUM>-<NUM> decouple from half barrel section <NUM> after fastener installation or trimming is completed.

The traveling workstation <NUM>-<NUM>, traveling workstation <NUM>-<NUM> and traveling workstation <NUM>-<NUM> then return to a placement point <NUM>-<NUM>, <NUM>-<NUM>, respectively. An embodiment has the traveling workstation <NUM>-<NUM>, traveling workstation <NUM>-<NUM> and traveling workstation <NUM>-<NUM> traveling back to the placement point <NUM>-<NUM>, <NUM>-<NUM> on their own power with an onboard crawler configuration. Retractable wheels (not shown) are arrayed along the first flexible rail <NUM>, <NUM>-<NUM>, <NUM>-<NUM> and the second flexible rail <NUM>, <NUM>-<NUM>, <NUM>-<NUM> and the carrier <NUM>, <NUM>-<NUM>, <NUM>-<NUM>. When in crawler configuration, traveling workstation <NUM>-<NUM>, traveling workstation <NUM>-<NUM> and traveling workstation <NUM>-<NUM> travel on their own power from the coupled point on half barrel section <NUM> to another couple point on half barrel section <NUM> and then recouple. Another configuration has <NUM>-<NUM>, traveling workstation <NUM>-<NUM> and traveling workstation <NUM>-<NUM> traveling on their own power back to placement point <NUM>-<NUM>, <NUM>-<NUM> as part of step <NUM>. An embodiment may have multiple traveling workstations <NUM>-<NUM>, traveling workstations <NUM>-<NUM> and traveling workstations <NUM>-<NUM> travelling along with half barrel section <NUM> at any one time. Furthermore, prior to having the windows or doors manufacturing excess <NUM> removed, the frames <NUM> and window surround <NUM> and door surrounds <NUM>-<NUM> are added to stiffen the half barrel section <NUM> and then windows or doors manufacturing excess <NUM> is removed. While only traveling workstations <NUM>-<NUM>, <NUM>-<NUM> and <NUM>-<NUM> are shown, more traveling workstations are possible.

<FIG> is a perspective view of a half barrel section <NUM> of fuselage traveling through fuselage assembly system <NUM> in an illustrative embodiment. In this embodiment, the half barrel section <NUM> includes a concavity <NUM>. Track <NUM> includes multiple stanchions <NUM> (e.g., pogos) which each include rollers <NUM> that secure and drive the half barrel section <NUM> in a process direction <NUM>.

<FIG> further depicts a factory floor <NUM>, and inner arch <NUM>-<NUM> and outer arch <NUM> which are affixed to the factory floor <NUM>. For clarity, workstations <NUM>, <NUM>-<NUM> are omitted from this illustration. To restate, inner arch <NUM>-<NUM> and outer arch <NUM> could be coupled to workstations <NUM>, <NUM>-<NUM> as an adjunct or as a standalone inner arch <NUM>-<NUM> and outer arch <NUM>. Inner arch <NUM>-<NUM> is dimensioned for contacting an IML <NUM> of a half barrel section <NUM> with wheels <NUM>-<NUM>. Inner arch <NUM>-<NUM> includes base <NUM>, which is fixed in position at the factory floor <NUM>. Inner arch <NUM>-<NUM> further includes wheels <NUM>-<NUM>. Each wheel <NUM>-<NUM> is rotatably affixed to the base <NUM>, and the wheels <NUM>-<NUM> are distributed circumferentially along the base <NUM>. The wheels <NUM>-<NUM> contact IML <NUM> when contacting IML <NUM> is needed to push half barrel section <NUM> into the desired contour <NUM>. In some embodiments, only a subset of wheels <NUM>-<NUM> engages with a half barrel section <NUM> when portions of the half barrel section <NUM> are not in contour <NUM>.

In another embodiment, in areas/locations where highly precise 3D positioning and contour <NUM> control are desired, several sets of wheels <NUM>-<NUM>, such as pairs of complementary wheels at a circumferential location along the stationary arches <NUM>-<NUM> may be placed into contact with half barrel section <NUM>. Multiple arches <NUM>-<NUM> with accompanied wheels <NUM>-<NUM> are located serially in workstations <NUM>, <NUM>-<NUM> along half barrel section <NUM> to more precisely enforce contour <NUM>. When the half barrel section <NUM> has contour <NUM>, then it has the desired OML <NUM> and IML <NUM>. In another embodiment, arch <NUM>-<NUM> with wheels <NUM>-<NUM> is included in at least one workstation <NUM>, <NUM>-<NUM>. In yet another embodiment, when workstation <NUM>, <NUM>-<NUM> has an arch like structure to accommodate fabrication within workstation <NUM>, <NUM>-<NUM> such as the arch like frames <NUM> holding drilling and fastener installing devices for frame <NUM> installation or for window surround <NUM> and door surround <NUM>-<NUM> installation, wheels <NUM>-<NUM> are added to arch <NUM>-<NUM> like structure to enforce contour <NUM> within workstation <NUM>, <NUM>-<NUM>.

In contrast, in areas where a less precisely contoured structure is desired, only one or two sets of wheels <NUM>-<NUM> per arch <NUM>-<NUM> are used, and only one arch <NUM>-<NUM> is employed. Another embodiment only uses arch <NUM>-<NUM> with wheels <NUM>-<NUM> without an OML arch like arch <NUM> and wheels <NUM> are utilized to maintain a desired contour <NUM> from IML <NUM> contact only. For example, while holding a desired shape for installing frames <NUM>, the half barrel section <NUM> is held less rigidly to enable frames <NUM>, window surround <NUM> or door surround <NUM>-<NUM> to be fastened to the half barrel section <NUM> easily without shimming.

In still further embodiments, wheels <NUM>-<NUM> are placed such that they do not contact an IML <NUM> of the half barrel section <NUM> unless the half barrel section <NUM> is out of contour <NUM>. Furthermore, an embodiment comprises the wheels <NUM>-<NUM> placed into contact with the half barrel section <NUM> during a pause between pulses, or during micro pulses <NUM> or pulses or during stints of continuous motion, but not during other times as the half barrel section <NUM> moves in the process direction <NUM>.

Outer arch <NUM> is dimensioned for contacting an OML <NUM> of a half barrel section <NUM>. Outer arch <NUM> includes base <NUM>, which is fixed in position at the factory floor <NUM>. Outer arch <NUM> further includes wheels <NUM>. Each wheel <NUM> is rotatably affixed to the outer arch <NUM>, and the wheels <NUM> are distributed circumferentially along the outer arch <NUM>. The wheels <NUM> contact OML <NUM> when contacting OML <NUM> is needed to push half barrel section <NUM> into the desired cross-sectional contour <NUM>. In some embodiments, only a subset of wheels <NUM> engages with a half barrel section <NUM> when portions of the half barrel section <NUM> are not in contour <NUM>.

In another embodiment, in areas/locations where highly precise 3D positioning and contour <NUM> control is desired, several sets of wheels <NUM>, such as pairs of wheels <NUM> at a circumferential location along the stationary arches <NUM> may be placed into contact with half barrel section <NUM>. Areas where more precise contour <NUM> control is needed, wheels <NUM> and/or <NUM>-<NUM> may be located along arch <NUM> and arch <NUM>-<NUM> whereas other areas with less precision could have wheels <NUM> or <NUM>-<NUM> omitted, respectively. Multiple arches <NUM> with accompanied wheels <NUM> are located serially in workstations <NUM>, <NUM>-<NUM> along half barrel section <NUM> to more precisely enforce contour <NUM>. In another embodiment, outer arch <NUM> with wheels <NUM> is included in at least one workstation <NUM>, <NUM>-<NUM>. In yet another embodiment, workstation <NUM>, <NUM>-<NUM> has an arch like structure to accommodate fabrication within workstation <NUM>, <NUM>-<NUM>. In such an embodiment, the arches <NUM>, <NUM>-<NUM> hold drilling and fastener installing devices for frame <NUM> installation or for window surround <NUM> and door surround <NUM>-<NUM> installation. Wheels <NUM>-<NUM> are added to arch <NUM>-<NUM> to enforce contour <NUM> within workstation <NUM>, <NUM>-<NUM>. In contrast, in areas where a less precisely contoured structure is desired, only one or two sets of wheels <NUM>-<NUM> per outer arch <NUM> with one outer arch <NUM> is employed. Another embodiment only uses outer arch <NUM> with wheels <NUM>, without an IML arch <NUM>-<NUM> and wheels <NUM>-<NUM> utilized, to maintain a desired contour <NUM> from OML <NUM> contact only. For example, while holding a desired shape for installing frames <NUM>, the half barrel section <NUM> is held less rigidly to enable frames <NUM>, window surrounds <NUM> or door surrounds <NUM>-<NUM> to be fastened to the half barrel section <NUM> easily without shimming.

In still further embodiments, wheels <NUM>, <NUM>-<NUM> are placed such that they do not contact the OML <NUM> and/or IML <NUM> of the half barrel section <NUM> unless the half barrel section <NUM> is out of contour <NUM>. Furthermore, an embodiment comprises the wheels <NUM>, <NUM>-<NUM> placed into contact with the half barrel section <NUM> during a pause between pulses, or during micro pulses <NUM> or pulses or during stints of continuous motion, but not during other times as the half barrel section <NUM> moves in the process direction <NUM>.

The stationary arches <NUM>-<NUM> discussed with regard to <FIG> are implemented as standalone devices in some embodiments and are integrated with respect to workstations <NUM>, <NUM>-<NUM> in other embodiments.

<FIG> is an illustration of a step prior to the <FIG> and two steps prior to <FIG> based upon view 4B-4B from <FIG>. In <FIG>, nip <NUM> is set at gap <NUM>-<NUM> to facilitate leading edge <NUM> initially passing between wheels <NUM>-<NUM>, <NUM>. Leading edge <NUM> has not yet passed between wheels <NUM>-<NUM>, <NUM>. Gap <NUM>-<NUM> is wider than gap <NUM> to facilitate leading edge <NUM> initially passing between wheels <NUM>-<NUM>, <NUM> if the half barrel section <NUM> is at radius <NUM>-<NUM>. In this embodiment, radius <NUM>-<NUM> is less than radius <NUM>. Gap <NUM>-<NUM> is wider than gap <NUM> to facilitate leading edge <NUM> initially passing between wheels <NUM>-<NUM>, <NUM> if the half barrel section <NUM> radius is at an uncorrected radius <NUM>-<NUM>. In the illustrated embodiment, radius <NUM>-<NUM> is less than radius <NUM>. Wheels <NUM>-<NUM> are also set at a radius <NUM>-<NUM> that is less than radius <NUM> or radius <NUM>-<NUM>. Setting the wheels <NUM>-<NUM>, <NUM> at gap <NUM>-<NUM> and wheels <NUM>-<NUM> at radius <NUM>-<NUM> avoids having leading edge <NUM> impinge upon wheels <NUM>-<NUM>, <NUM> so that micro pulsing of half barrel section <NUM> is not blocked by leading edge <NUM> impinging upon wheels <NUM>-<NUM>, <NUM>. Impinging may prevent micro pulsing. In a different embodiment, wheels <NUM>-<NUM> are also set at a radius <NUM>-<NUM> when radius <NUM>-<NUM> is greater than radius <NUM>. The radius <NUM>-<NUM> would be set at a radius of <NUM>. In another embodiment, radius <NUM>-<NUM> is greater than <NUM> at some locations and less than <NUM> at other locations hoopwise <NUM> locations relative to arches <NUM>-<NUM>, <NUM>. Hoopwise <NUM>, wheels <NUM>-<NUM>, <NUM> are positioned with an appropriate radius <NUM>-<NUM> and nip <NUM> gap of <NUM>-<NUM> to be complementary to the radius <NUM>-<NUM>.

The arches <NUM>, <NUM>-<NUM>, are located after Non-Destructive Inspection station (NDI) <NUM>, <NUM>-<NUM> (shown in <FIG>). The NDI station <NUM>, <NUM>-<NUM> measure the radius <NUM>-<NUM> of the half barrel section hoopwise <NUM> during each micro pulse <NUM>. The half barrel section <NUM> is micro pulsed through the NDI station <NUM>, <NUM>-<NUM>. NDI station <NUM> performs outer NDI inspection upon half barrel section <NUM> while NDI station <NUM>-<NUM> performs inner NDI inspection upon half barrel section <NUM>. The radius <NUM>-<NUM> is measured hoopwise <NUM> on half barrel section <NUM> when half barrel section <NUM> passes through an NDI station <NUM>, <NUM>-<NUM> either in micro pulse <NUM> or continuously. This radius measurement could be performed optically, mechanically or by other suitable means. This measurement information establishes the radius <NUM>-<NUM> hoopwise <NUM> for the half barrel section <NUM> within the purview <NUM>-<NUM> of NDI station <NUM>, <NUM>-<NUM>. This measurement information for the purview <NUM>-<NUM> for half barrel section <NUM> is passed on via controller <NUM> for use when that same measured portion of half barrel section <NUM> is in purview <NUM>-<NUM>, <NUM>-<NUM> of arches <NUM>, <NUM>-<NUM>, respectively. This measurement information is used to set the radius <NUM>-<NUM> and nip <NUM> gap <NUM>-<NUM>.

<FIG> is an illustration of a step prior to the step of <FIG>. In <FIG>, nip <NUM> is set at gap <NUM>-<NUM> to facilitate leading edge <NUM> initially passing between wheels <NUM>-<NUM>, <NUM>. Gap <NUM>-<NUM> is wider than gap <NUM> to facilitate leading edge <NUM> initially passing between wheels <NUM>-<NUM>, <NUM> if the half barrel section <NUM> radius is at an uncorrected radius <NUM>-<NUM>. In the illustrated embodiment, radius <NUM>-<NUM> is less than radius <NUM>. In another embodiment, radius <NUM>-<NUM> is greater than <NUM>. Wheels <NUM>-<NUM> are also set at a radius <NUM>-<NUM> that is less than radius <NUM> or radius <NUM>-<NUM>. Setting the wheels <NUM>-<NUM>, <NUM> at gap <NUM>-<NUM> and wheels <NUM>-<NUM> at radius <NUM>-<NUM> avoids having leading edge <NUM> impinge upon either wheels <NUM>-<NUM>, <NUM> so that micro pulsing of half barrel section <NUM> is not blocked by leading edge <NUM> impinging upon wheels <NUM>-<NUM>, <NUM>. Impinging may prevent micro pulsing. Half barrel section <NUM> is then pulsed so that leading edge <NUM> passes through nip <NUM>.

Then controller <NUM> instructs the connectors <NUM>, <NUM>-<NUM>, <NUM>, <NUM>-<NUM> to form nip <NUM> at gap <NUM> as shown in <FIG>. Forming the nip <NUM> at gap <NUM> is the first step at establishing a contour <NUM> in half barrel section <NUM>. The nip <NUM> is located after indexing to facilitate leading edge <NUM> of half barrel section <NUM> sliding into nip <NUM> during a micro pulse <NUM>. If needed, wheels <NUM>-<NUM> and <NUM> then enforce contour <NUM> onto half barrel section <NUM> by pushing it towards its respective arch <NUM>, <NUM>-<NUM> as it proceeds in process direction <NUM>. Contour <NUM> enforcement occurs after leading edge <NUM> passes through nip <NUM> set at gap <NUM> after being set at gap <NUM>-<NUM>.

<FIG> is a section cut view 4B-4B of wheels <NUM>-<NUM>, <NUM> on arch <NUM>-<NUM> and arch <NUM>, inner and outer respectively, that that enforces a contour <NUM> in <FIG>. In <FIG>, wheels <NUM>-<NUM> are illustrated as contacting the IML <NUM>, while wheels <NUM> are illustrated as contacting the OML <NUM>. A nip <NUM> is formed between wheel <NUM>-<NUM> and wheel <NUM>. The wheels <NUM> spin counter clockwise <NUM> as the half barrel section <NUM> proceeds through nip <NUM> in process direction <NUM>. The wheels <NUM>-<NUM> spin clockwise <NUM>-<NUM> as the half barrel section <NUM> proceeds through nip <NUM> in process direction <NUM>. In one embodiment, the gap <NUM> between wheels <NUM>-<NUM> and OML <NUM> is too great for a nip <NUM> to be formed. In other embodiments, the wheels <NUM>-<NUM> and wheels <NUM> together form a nip <NUM> that forces a lengthwise portion <NUM> (<FIG>) of the half barrel section <NUM> between them into a desired contour <NUM>. When multiple wheels <NUM>-<NUM>, <NUM> circumferentially aligned along an inner arch <NUM>-<NUM> and outer arch <NUM> perform this action, the nip <NUM> enforce a cross-sectional contour <NUM> along the entirety of the IML <NUM> and/or OML <NUM> of half barrel section <NUM>. Wheel mounts <NUM>, <NUM> are employed to hold wheels <NUM>-<NUM> and <NUM>, respectively on an axles <NUM>. Wheel mounts <NUM>, <NUM> are attached by connectors <NUM>, <NUM> and connector <NUM>-<NUM>, <NUM>-<NUM> to arch <NUM>-<NUM> and arch <NUM>, respectively. Connectors <NUM>, <NUM> and connectors <NUM>-<NUM>, <NUM>-<NUM> are extendable and retractable relative to arch <NUM>-<NUM> and arch <NUM> in direction of length <NUM>, <NUM>-<NUM>, respectively. The wheels <NUM>-<NUM>, <NUM> are moved relative to arch <NUM>-<NUM> and arch <NUM> by connectors <NUM>, <NUM> and connectors <NUM>-<NUM>, <NUM>-<NUM>, respectively.

The connectors <NUM>, <NUM> and connectors <NUM>-<NUM>, <NUM>-<NUM> are hydraulic, electric, mechanical actuators and/or other suitable actuators. The mechanical actuators are a screw jack or a similar device. The wheels <NUM>-<NUM> and <NUM> are moved relative to the arches <NUM>, <NUM>-<NUM> by connectors <NUM>-<NUM>, <NUM>-<NUM> and connectors <NUM>, <NUM>, respectively, and to place the nip <NUM> where needed to facilitate contour <NUM> enforcement within the purview <NUM>-<NUM>, <NUM>-<NUM> of arches <NUM>, <NUM>-<NUM> based upon information conveyed to arches <NUM>, <NUM>-<NUM> via indexing from half barrel section <NUM>. Based upon index conveyed information to arches <NUM>, <NUM>-<NUM>, the controller <NUM> instructs the connectors <NUM>, <NUM>-<NUM>, <NUM>, <NUM>-<NUM> to reach length <NUM>, <NUM>-<NUM>. The controller <NUM> positions the wheels <NUM>, <NUM>-<NUM> to form a nip <NUM> at the desired radius <NUM>. This process, using the arches <NUM>, <NUM>-<NUM>, is used to enforce a contour <NUM> onto the half barrel section <NUM> within the purview <NUM> of an adjacent workstation <NUM>, <NUM>-<NUM> during the micro pulse <NUM> or pause between micro pulses <NUM>. This permits a forcing of half barrel section <NUM> into contour <NUM> transiently within workstations <NUM>, <NUM>-<NUM> when contour <NUM> is out of tolerance.

<FIG> illustrates enforcing a contour <NUM> in half barrel section <NUM> with a radius <NUM>-<NUM>. Radius <NUM>-<NUM> is less than radius <NUM>. Connectors <NUM>, <NUM> and connectors <NUM>-<NUM>, <NUM>-<NUM> are extendable and retractable relative to arches <NUM>, <NUM>-<NUM> in direction of length <NUM>, <NUM>-<NUM>, respectively. The wheels <NUM>, <NUM>-<NUM> are moved relative to arches <NUM>, <NUM>-<NUM> by connectors <NUM>, <NUM> and connectors <NUM>-<NUM>, <NUM>-<NUM>, respectively. The connectors <NUM>, <NUM> and connectors <NUM>-<NUM>, <NUM>-<NUM> are hydraulic, electric, and or mechanical actuators. The mechanical actuators are a screw jack or a similar device. The wheels <NUM>, <NUM>-<NUM> are moved relative to the arches <NUM>, <NUM>-<NUM> by connectors <NUM>-<NUM>, <NUM>-<NUM> and connectors <NUM>, <NUM>, respectively, and to place the nip <NUM> where needed to facilitate contour <NUM> enforcement within the purview <NUM>-<NUM>, <NUM>-<NUM> of arches <NUM>, <NUM>-<NUM>.

Contour <NUM> enforcement is based upon information conveyed to arches <NUM>, <NUM>-<NUM> via indexing from half barrel section <NUM>. Based upon index conveyed information to arches <NUM>, <NUM>-<NUM>, the controller <NUM> instructs the connectors <NUM>, <NUM>-<NUM>, <NUM>, <NUM>-<NUM> to reach length <NUM>, <NUM>-<NUM>. The controller <NUM> positions the wheels <NUM>, <NUM>-<NUM> to form a nip <NUM> at the desired radius <NUM>-<NUM>. Preliminarily, nip <NUM> is set at gap <NUM>-<NUM> to facilitate leading edge <NUM> initially passing between wheels <NUM>, <NUM>-<NUM>. Then controller <NUM> instructs the connectors <NUM>, <NUM>-<NUM>, <NUM>, <NUM>-<NUM> to form nip <NUM> at gap <NUM>. Forming the nip <NUM> at gap <NUM> is the first step at establishing a contour <NUM> in half barrel section <NUM>. When the nip <NUM> is located after indexing, leading edge <NUM> of half barrel section <NUM> slides into nip <NUM> during a micro pulse <NUM> and, if needed, wheels <NUM>-<NUM> and <NUM> enforce contour <NUM> onto half barrel section <NUM>, <NUM> by pushing it towards its respective arch <NUM>, <NUM>-<NUM>.

<FIG> is a section cut view <NUM>-<NUM> of wheels <NUM>-<NUM>, <NUM> on inner arch <NUM>-<NUM> and outer arch <NUM> that enforces a contour <NUM> in in <FIG>. Wheel mounts <NUM>-<NUM> and <NUM>-<NUM> are employed to hold wheels <NUM>-<NUM> and <NUM>, respectively on an axles <NUM>. Wheel mounts <NUM>-<NUM> and <NUM>-<NUM> have been enhanced with intake rollers <NUM>, <NUM>-<NUM> disposed on swing arms <NUM>, <NUM>-<NUM> which pivot about axes <NUM> upstream of nip <NUM> and are biased with a default force F towards half barrel section <NUM>. The intake rollers <NUM> are separated by a gap G, and are held in position with a default amount of force F. However, the intake rollers <NUM> are capable of pivoting <NUM> on swing arms <NUM> about axes <NUM>. Because the swing arms <NUM> are biased to return to a default position with regard to the axes <NUM>, the swing arms <NUM> push/force the intake rollers <NUM> into contact with half barrel section <NUM>. This means that if a new half barrel section <NUM> is about to enter between arches <NUM>, <NUM>-<NUM> but is not perfectly aligned, the intake rollers <NUM> are capable of pre-contouring half barrel section <NUM> through pre-nip <NUM> more gradually into contour <NUM> than with just nip <NUM>. Pre-nip <NUM> helps bring leading edge <NUM> of half barrel section <NUM> into nip <NUM> as part of a precursor contouring device to avoid a stoppage of process direction <NUM> by leading edge <NUM> impingement upon <NUM>-<NUM> or <NUM> for a half barrel section <NUM> substantially out of contour <NUM>. The leading edge <NUM> is pre-contoured through pre-nip <NUM> as a precursor to being placed into contour <NUM> by nip <NUM>.

<FIG> is a side view illustrating an example embodiment of system <NUM> which includes stationary arches <NUM>-<NUM>, <NUM> that enforce a contour <NUM>, and downstream workstations <NUM>, <NUM>-<NUM>. In this embodiment, a half barrel section <NUM> of fuselage <NUM> is carried along stanchions <NUM>, which are mounted to factory floor <NUM>. An inner arch <NUM>-<NUM> and an outer arch <NUM> enforce a contour <NUM> (shown in <FIG>) onto the half barrel section <NUM>, which proceeds in a process direction <NUM> and extends through multiple workstations <NUM>, <NUM>-<NUM>. During pauses between micro pulses <NUM>, or during continuous motion, end effectors <NUM> at the workstations <NUM>, <NUM>-<NUM> perform work on the half barrel section <NUM> to assemble a completed half barrel section (e.g., <NUM>) for joining with another half barrel section (e.g., <NUM>). In one embodiment, the end effectors <NUM> operate to install frame <NUM> or door surround <NUM>-<NUM> and/or window surrounds <NUM>, which stiffen half barrel section <NUM> and reduce or eliminate the need for additional arches.

Traveling workstations <NUM>-<NUM> and <NUM>-<NUM> are attached in workstation <NUM> and travels with half barrel section <NUM> while performing work during micro pulses <NUM> and/or pauses between micro pulses <NUM>. Traveling workstations <NUM>-<NUM> and <NUM>-<NUM> are, in one example, flex track type systems. Traveling workstations <NUM>-<NUM> include a flex track for installing frame <NUM> installation fasteners. Traveling workstation <NUM>-<NUM> is a flex track for installing window surround <NUM> installation fasteners. When placed, the traveling workstation <NUM>-<NUM> and <NUM>-<NUM> drills fastener holes and installs fasteners to attach frames <NUM> and window surrounds <NUM>.

Referring back to <FIG>, the traveling workstation <NUM>-<NUM> separates manufacturing excess <NUM> from half barrel section <NUM> after window surrounds <NUM> and frames <NUM> are installed. The traveling workstations <NUM>-<NUM>, <NUM>-<NUM> travel along with the half barrel section <NUM> like a "hitch hiker" to a removal point <NUM>, for example, and then are returned to a placement point <NUM>-<NUM> and are loaded/unloaded via a robot or other system for reattachment and further work on another portion of half barrel section <NUM>, or the next half barrel section to pulse down the track <NUM>. An embodiment may have multiple traveling workstations <NUM>-<NUM>, <NUM>-<NUM> travelling along with half barrel section <NUM> at any one time.

<FIG> is a more detailed illustration of traveling workstation <NUM>-<NUM> coupled to half barrel section <NUM>. The flexible-rail system <NUM> comprises a plurality of attachment vacuum cups <NUM> releasably affixed at spaced intervals along the length of a first flexible rail <NUM> and a second flexible rail <NUM> to half barrel section <NUM>. A vacuum source <NUM> is connected by hoses (not shown) to vacuum cups <NUM> to provide attachment force. One vacuum source <NUM> serves vacuum cups <NUM> on first flexible rail <NUM> while the other vacuum source <NUM> serves the vacuum cups <NUM> on second flexible rail <NUM>. Two vacuum source <NUM> locations are shown whereas one may be sufficient. The second flexible rail <NUM> is preferably parallel to and spaced apart from the first rail <NUM>. The first flexible rail <NUM> and the second flexible rail <NUM> are located beyond the perimeter of the window surround fastener locations <NUM>. While a number of fastener installation locations <NUM> are shown, the actual number of fastener install locations <NUM> are more or less. Other suitable attachment components may also be used, such as magnetic coupling to an inner ferromagnetic surface. First flexible rail <NUM> and the second flexible rail <NUM> are connected by spacer <NUM> and spacer <NUM>. First flexible rail <NUM> and the second flexible rail <NUM> are drawn into a shape complementary to half barrel section <NUM> when vacuum or magnetically coupled. Traveling workstation <NUM>-<NUM> is mounted upon half barrel section <NUM>, for example, in workstation <NUM>-<NUM>.

A drilling tool <NUM> and fastener install tool <NUM> is located in a carrier <NUM>. Carrier <NUM> is moveably coupled to the first flexible rail <NUM> and the second flexible rail <NUM>. The moveably coupling includes a rack and pinion system or similar system not shown. Lateral alignment <NUM> moves the drilling tool <NUM> and fastener install tool <NUM> laterally across the carrier <NUM> relative to the first flexible rail <NUM> and the second flexible rail <NUM>. A lateral screw jack system is shown, but other actuations systems are possible. A fastener feeder <NUM> feeds fasteners to fastener install tool <NUM> for driving into fastener installation locations <NUM> created by drilling tool <NUM> in half barrel section <NUM>. Another embodiment has the vacuum cups <NUM> released from half barrel section <NUM> and then manually or automatically returned to placement point <NUM>-<NUM>.

<FIG> illustrates traveling workstation <NUM>-<NUM> coupled to half barrel section <NUM>. The flexible-rail system <NUM>-<NUM> comprises a plurality of attachment vacuum cups <NUM>-<NUM> releasably affixed at spaced intervals along the length of a first flexible rail <NUM>-<NUM> and a second flexible rail <NUM>-<NUM> to half barrel section <NUM>. A vacuum source <NUM>-<NUM> is connected by hoses (not shown) to vacuum cups <NUM>-<NUM> to provide attachment force. One vacuum source <NUM>-<NUM> serves vacuum cups <NUM>-<NUM> on first flexible rail <NUM>-<NUM> while the other vacuum source <NUM>-<NUM> serves the vacuum cups <NUM>-<NUM> on second flexible rail <NUM>-<NUM>. Two vacuum source <NUM>-<NUM> locations are shown whereas one may be sufficient. The second flexible rail <NUM>-<NUM> is preferably parallel to and spaced apart from the first rail <NUM>-<NUM>. The first flexible rail <NUM>-<NUM> and the second flexible rail <NUM>-<NUM> are located beyond the perimeter of the window surround fastener locations <NUM>. While a number of fastener installation locations <NUM> are shown, the actual number of fastener install locations <NUM> are more or less. Other suitable attachment components may also be used, such as magnetic coupling to an inner ferromagnetic surface. First flexible rail <NUM>-<NUM> and the second flexible rail <NUM>-<NUM> are connected by spacer <NUM>-<NUM> and spacer <NUM>-<NUM>. First flexible rail <NUM> and the second flexible rail <NUM>-<NUM> to half barrel section <NUM> are drawn into a shape complementary to half barrel section <NUM> when vacuum or magnetically coupled. Traveling workstation <NUM>-<NUM> is mounted upon half barrel section <NUM>, for example, in workstation <NUM>-<NUM>.

A rough trimming tool <NUM>-<NUM> and a fine trimming tool <NUM>-<NUM> are located in a carrier <NUM>-<NUM>. Carrier <NUM>-<NUM> is moveably coupled to the first flexible rail <NUM>-<NUM> and the second flexible rail <NUM>-<NUM>. The moveably coupling includes a rack and pinion system or similar system not shown. Lateral alignment <NUM>-<NUM> moves the rough trimming tool <NUM>-<NUM> and the finer trimming tool <NUM>-<NUM> laterally across the carrier <NUM>-<NUM> relative to the first flexible rail <NUM>-<NUM> and the second flexible rail <NUM>-<NUM>. A lateral screw jack system is shown, but other actuations systems are possible here. A guidance system <NUM>-<NUM> guides the rough trimming tool <NUM>-<NUM> and a finer trimming tool <NUM>-<NUM>. The rough trimming tool <NUM>-<NUM> provides the first pass of the trimmer to separate the manufacturing excess <NUM> from half barrel section <NUM>. The finer trimming tool <NUM>-<NUM> creates the final trim line <NUM> within tolerance. Final trim line <NUM> is within a perimeter formed by fastener installation locations <NUM> and when completed forms a cutout of manufacturing excess <NUM>. Rough trimming tool <NUM>-<NUM> and fine trimming tool <NUM>-<NUM> are shown trimming in direction <NUM> initially. Rough trimming tool <NUM>-<NUM> and fine trimming tool <NUM>-<NUM> then progress in direction <NUM>, <NUM>, <NUM>. In other embodiments, rough trimming tool <NUM>-<NUM> and fine trimming tool <NUM>-<NUM> progress in direction <NUM>, <NUM>, <NUM>, <NUM> in an order of any combination of directions <NUM>, <NUM>, <NUM>, <NUM>. Rough trimming tool <NUM>-<NUM> and fine trimming tool <NUM>-<NUM>, in another embodiment, progress in a direction opposite to direction <NUM>, <NUM>, <NUM>, <NUM>. Another embodiment has the vacuum cups <NUM>-<NUM> released from half barrel section <NUM> and then manually or automatically returned to placement point <NUM>-<NUM>.

<FIG> illustrates traveling workstation <NUM>-<NUM> coupled to half barrel section <NUM>. The flexible-rail system <NUM>-<NUM> comprises a plurality of attachment vacuum cups <NUM>-<NUM> releasably affixed at spaced intervals along the length of a first flexible rail <NUM>-<NUM> and a second flexible rail <NUM>-<NUM> to half barrel section <NUM>. A vacuum source <NUM>-<NUM> is connected by hoses to vacuum cups <NUM>-<NUM> to provide attachment force. One vacuum source <NUM>-<NUM> serves vacuum cups <NUM>-<NUM> on first flexible rail <NUM>-<NUM> while the other vacuum source <NUM>-<NUM> serves the vacuum cups <NUM>-<NUM> on second flexible rail <NUM>-<NUM>. Two vacuum source <NUM>-<NUM> locations are shown whereas one may be sufficient. The second flexible rail <NUM>-<NUM> is preferably parallel to and spaced apart from the first rail <NUM>-<NUM>. The first flexible rail <NUM>-<NUM> and the second flexible rail <NUM>-<NUM> are located roughly parallel to frame <NUM> fastener locations <NUM>. An embodiment has first flexible rail <NUM>-<NUM> on one side of fastener locations <NUM> and second flexible rail <NUM>-<NUM> on the opposite side. While a number of fastener installation locations <NUM> are shown, the actual number of fastener install locations <NUM> are more or less. Other suitable attachment components may also be used, such as magnetic coupling to an inner ferromagnetic surface. First flexible rail <NUM>-<NUM> and the second flexible rail <NUM>-<NUM> are connected by spacer <NUM>-<NUM> and spacer <NUM>-<NUM>. First flexible rail <NUM>-<NUM> and the second flexible rail <NUM>-<NUM> to half barrel section <NUM> are drawn into a shape complementary to half barrel section <NUM> when vacuum or magnetically coupled. Traveling workstation <NUM>-<NUM> is mounted upon half barrel section <NUM> in workstation <NUM>.

A drilling tool <NUM>-<NUM> and fastener install tool <NUM>-<NUM> are located in a carrier <NUM>-<NUM>. Carrier <NUM>-<NUM> is moveably coupled to the first flexible rail <NUM>-<NUM> and the second flexible rail <NUM>-<NUM>. The moveably coupling includes a rack and pinion system or similar system not shown. Lateral alignment <NUM>-<NUM> moves the drilling tool <NUM>-<NUM> and fastener install tool <NUM>-<NUM> laterally across the carrier <NUM>-<NUM> relative to the first flexible rail <NUM>-<NUM> and the second flexible rail <NUM>-<NUM>. A lateral screw jack system <NUM> is shown, but other actuations systems are possible here. A fastener feeder <NUM>-<NUM> feeds fasteners to fastener install tool <NUM>-<NUM> for driving into fastener installation locations <NUM> created by drilling tool <NUM>-<NUM> in half barrel section <NUM>. Carrier <NUM>-<NUM> moves in a hoopwise direction <NUM> on first flexible rail <NUM>-<NUM> and second flexible rail <NUM>-<NUM> during fastener installation. Hoopwise direction <NUM> is parallel to frame <NUM>.

An embodiment has the first flexible rail <NUM>-<NUM> and the second flexible rail <NUM>-<NUM> extending in hoopwise direction <NUM> from bearing edge <NUM> to bearing edge <NUM> across the crown up position <NUM> or keel up position <NUM> of the half barrel section <NUM>. This embodiment has more than the one each of spacers <NUM>-<NUM> and spacer <NUM>-<NUM>. This embodiment has a spacer <NUM>-<NUM> or spacer <NUM>-<NUM> arrayed in several locations along the hoopwise direction <NUM> including at least near each bearing edge <NUM> and near the crown up position <NUM> or keel up position <NUM> of the half barrel section <NUM>. An embodiment has traveling workstation <NUM>-<NUM> in a crawler configuration. Retractable wheels <NUM> are arrayed along the first flexible rail <NUM>-<NUM> and the second flexible rail <NUM>-<NUM> and the carrier <NUM>-<NUM>. The crawler version of traveling workstation <NUM>-<NUM> is located upon half barrel section <NUM> and then perform fastener installation to join frame <NUM> to half barrel section <NUM>. Then the wheels <NUM> are deployed and the vacuum cups <NUM>-<NUM> are released from half barrel section <NUM>. The traveling workstation <NUM>-<NUM> then crawls upon wheels <NUM> along half barrel section <NUM> towards placement point <NUM>-<NUM>. Controller <NUM> directs the crawling of the traveling workstation <NUM>-<NUM> along the half barrel section <NUM>. Another embodiment has the vacuum cups <NUM>-<NUM> of traveling workstations <NUM>-<NUM>, <NUM>-<NUM>, <NUM>-<NUM> released from half barrel section <NUM> and then manually or automatically return traveling workstations <NUM>-<NUM>, <NUM>-<NUM>, <NUM>-<NUM> to placement point <NUM>-<NUM>.

In the following examples, additional processes, systems, and methods are described in the context of a fuselage assembly system.

Referring more particularly to the drawings, embodiments of the disclosure may be described in the context of aircraft manufacturing and service in method <NUM> as shown in <FIG> and an aircraft <NUM> as shown in <FIG>. Aircraft <NUM> is, in one embodiment, the same as aircraft <NUM> of <FIG>. During pre-production, method <NUM> may include specification and design <NUM> of the aircraft <NUM> and material procurement <NUM>. During production, component and subassembly manufacturing <NUM> and system integration <NUM> of the aircraft <NUM> takes place. Thereafter, the aircraft <NUM> may go through certification and delivery <NUM> in order to be placed in service <NUM>. While in service by a customer, the aircraft <NUM> is scheduled for routine work in maintenance and service <NUM> (which may also include modification, reconfiguration, refurbishment, and so on). Apparatus and methods embodied herein may be employed during any one or more suitable stages of the production and service described in method <NUM> (e.g., specification and design <NUM>, material procurement <NUM>, component and subassembly manufacturing <NUM>, system integration <NUM>, certification and delivery <NUM>, service <NUM>, maintenance and service <NUM>) and/or any suitable component of aircraft <NUM> (e.g., airframe <NUM>, systems <NUM>, interior <NUM>, propulsion system <NUM>, electrical system <NUM>, hydraulic system <NUM>, environmental <NUM>).

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

As already mentioned above, apparatus and methods embodied herein may be employed during any one or more of the stages of the production and service described in method <NUM>. For example, components or subassemblies corresponding to component and subassembly manufacturing <NUM> may be fabricated or manufactured in a manner similar to components or subassemblies produced while the aircraft <NUM> is in service. Also, one or more apparatus embodiments, method embodiments, or a combination thereof may be utilized during the subassembly manufacturing <NUM> and system integration <NUM>, for example, by substantially expediting assembly of or reducing the cost of an aircraft <NUM>. Similarly, one or more of apparatus embodiments, method embodiments, or a combination thereof may be utilized while the aircraft <NUM> is in service, for example and without limitation during the maintenance and service <NUM>. Thus, the disclosure may be used in any stages discussed herein, or any combination thereof, such as specification and design <NUM>, material procurement <NUM>, component and subassembly manufacturing <NUM>, system integration <NUM>, certification and delivery <NUM>, service <NUM>, maintenance and service <NUM> and/or any suitable component of aircraft <NUM> (e.g., airframe <NUM>, systems <NUM>, interior <NUM>, propulsion system <NUM>, electrical system <NUM>, hydraulic system <NUM>, and/or environmental <NUM>).

Claim 1:
A method for assembling a section of a fuselage (<NUM>) of an aircraft (<NUM>), the method comprising:
pulsing a half barrel section (<NUM>) of the fuselage (<NUM>) along a track (<NUM>) in a process direction (<NUM>);
utilizing an indexing feature (<NUM>) associated with the half barrel section (<NUM>) to determine a desired contour (<NUM>) for a portion of the half barrel section (<NUM>); and
enforcing the desired contour (<NUM>) onto the half barrel section (<NUM>) using components that enforce an inner mold line (<NUM>) and components that enforce an outer mold line (<NUM>) when the contour of the half barrel section (<NUM>) is out of tolerance from the desired contour (<NUM>).