Patent ID: 12242242

DESCRIPTION

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.

Composite parts, such as Carbon Fiber Reinforced Polymer (CFRP) parts, are initially laid-up onto a rigid layup mandrel 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 curing. 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.

FIG.1is a block diagram of a line assembly system100for a composite part in an illustrative embodiment. Line assembly system100comprises any system, device, or component operable to iteratively pulse a layup mandrel120(e.g. for a half-barrel section of fuselage approximately twenty to forty feet long) along a track110or other pathway in a process direction127(e.g., via an Autonomous Guided Vehicle (AGV). For example, the layup mandrel120may be pulsed for its entire length, a fraction of its length (e.g., a few inches), or may be continuously moved in the process direction127. Line assembly system100is further capable of laying up a laminate comprising layers of fiber-reinforced material onto the layup mandrel120(e.g., in pauses between pulses, or during continuous motion of the layup mandrel120).

In this embodiment, the line assembly system100includes tracks110, which transport the layup mandrel120(or other rigid tool125) in a process direction127. The layup mandrel120includes a first side surface122, a second side surface124, and a layup surface129. A lamination machine150applies a laminate (not shown inFIG.1) in layup region130of the layup mandrel120. This laminate will be hardened into a composite part after the layup mandrel120is further transported in the process direction127. The operations of the lamination machine150and/or other stations disposed in serial along the process direction127are managed by controller112. In one embodiment, controller112determines a progress of the layup mandrel120along the track110(e.g., based on input from a technician, in accordance with an automated process such as input from a camera or physical sensor, such as a linear or rotary actuator), and uses this input to manage the operations of the lamination machine150in accordance with instructions stored in a Numerical Control (NC) program. Controller112may be implemented, for example, as custom circuitry, as a hardware processor executing programmed instructions, or some combination thereof.

The lamination machine150moves along a frame140via actuators152, and includes a lamination head160that performs layup of fiber-reinforced material. Lamination head160places fiber-reinforced material upon layup mandrel120or a prior placed ply of fiber-reinforced material to create a lamination. The lamination head160includes a roller162that travels along a layup surface129of the layup mandrel120, and further includes a suspension164which permits limited displacement of the roller162along all three axes. The suspension164supports the roller162while permitting limited deflection of the roller162by the layup surface129. For example, the suspension164may press the roller162into the layup surface129, resulting in deflection from a default position if the layup surface129is above or below an expected position. The lamination head160further includes a position sensor168(e.g., a linear sensor, laser sensor, infrared sensor, etc.) that detects displacement of the roller162along three dimensions. Lamination head160further includes a dispenser166which applies tows of unidirectional fiber reinforced material (e.g., CFRP) in accordance with instructions from the NC program114stored in controller112.

Because the layup mandrel120may be tens of feet long, even small angular deviations of the layup mandrel120from an expected orientation result in substantial differences in the locations where tows are placed by the lamination machine150. For example, an angular deviation of less than a degree may result in inches of positional offset at one or more locations on the layup mandrel120. This presents a problem because tows are expected to be placed in precise locations and orientations at the layup mandrel120(e.g., locations that are specified to within fractions of an inch). Furthermore, gaps and/or overlaps between tows beyond tolerance are not permissible. To address these concerns and ensure that layup is performed in a desired manner without a need to reorient the layup mandrel120, the line assembly system100includes one or more of the following components discussed below to facilitate indexing of the layup mandrel120to the lamination machine150. Furthermore, localized variations may exist at the layup mandrel120, for example if a component placed at the layup mandrel120deviates from an expected position.

In one embodiment, the roller162of the lamination head160utilizes the position sensor168to determine displacement over time as the roller162proceeds along a layup surface129of the layup mandrel120. For example, the roller162may traverse first side surface122or second side surface124by following a nominal (expected) path (i.e., a path comprising a series of 3D coordinates), and deviations from the nominal path123may be recorded by the position sensor168at each of multiple locations along the surface(s) that were traversed. Controller112may then alter the NC program114to account for these differences. It is understood that NC program114includes a portion that controls the indexing operations described herein as well as a portion that controls the placement of composites materials such as fiber tows.

In a further embodiment, the lamination machine150is placed a predetermined and precisely known offset O from an indexing head170. In various embodiments, lamination machine150includes an indexing head170, or lamination machine150swaps out its lamination head160for an indexing head170. In such an embodiment, the indexing head170includes an indexing end172that traverses grooves, for example first groove126and/or second groove128, that have been precisely placed onto/machined into the layup mandrel120(or other rigid tool125) (e.g., to within tolerance), and a sensor174records positional deviations from an expected nominal path of the indexing end172as the indexing end172traverses the first groove126and/or second groove128. The deviations may be recorded, for example, once per half-inch of travel of the roller162, and may be recorded to tolerance requirements. This information may be utilized by controller112to update the NC program114.

In one embodiment, indexing is performed at least according to the following description. A layup mandrel120(also referred to herein as a tool, a rigid tool125, and an arcuate tool) is carried upon a track110comprising a rail system (e.g., embedded within the floor, affixed to the floor, etc.). The rails are positioned in locations known to the controller112. The layup mandrel120has been fabricated according to precise dimensions, and this precise layup enables the layup mandrel120to be precisely located based on a traversal of its surface(s) (e.g., first side122and/or second side124) or groove(s) (e.g., first groove126and/or second groove128). Thus, once this rigid tool125has been traversed by a roller162or indexing head170, the 3D position and orientation of the rigid tool125is known, without the need for a full scan via probes or optical technology at each station in an assembly line.

Traversal by a roller162or indexing head170therefore operates as a short cut to characterizing surface geometry and orientation, without the need for a full scan via probes or optical technology at each station, such as lamination machine150, in an assembly line. This technique benefits from the rigidity of the layup mandrel120(or its lack of deflection, particularly deflection outside of tolerance) as it passes through the lamination machine150from one micro pulse to the next. A micro pulse is an advancement of the layup mandrel120by a distance less than the length of the layup mandrel120. A pulse is an advancement of the layup mandrel120by a distance equal to or greater than the length of the layup mandrel120. The preciseness of the tooling, the layup upon the tooling, and the lack of change to the tooling and the layup due to rigidity of the system from one micro pulse to the next enables characterization of the structure being micro pulsed, without rescanning after each pulse. The pulsing does not sufficiently disrupt the configuration of the layup mandrel120nor does it disrupt a preform upon it. Hence, the technique of characterization may be repeated successfully after each micro pulse.

Because of the precise indexing performed, the lamination machine150(or another other tool) at a station in an assembly line knows exactly where it is relative to the rigid tool125, such as layup mandrel120, before work is performed at the layup mandrel120. The 3D position and orientation of the rigid tool125is then established or indexed into any NC programming or other automated system in use at the station. After initially establishing this information, downstream stations or tools may assume that the layup mandrel120has not changed its orientation and/or contour as it proceeds, or pulses, along the assembly line. Therefore, no setup time or scanning is needed after each micro pulse of the rigid tool125by a distance in the process direction127(e.g., a micro pulse of one foot, several inches, a pulse of an entire length of the rigid tool125, etc.). That is, because the precise shape of the rigid tool125is already known (i.e., to within tolerance), traversing sides122,124, traversing grooves126,128and/or layup surfaces129are precisely fabricated into the layup mandrel120enables the controller112to determine a precise orientation and/or location of the rigid tool125(e.g., to within tolerance) relative to a lamination machine150. When the two are in a known relationship, layup operations at the lamination machine150can be altered to accommodate the rigid tool125.

In one embodiment, lamination machine150comprises one of multiple stations that are disposed along the tracks110and are separated in the process direction127by less than the length of the rigid tool125. Work performed by other stations may comprise performing additional layup, inspecting a green (uncured) laminate, and/or performing other tasks.

Illustrative details of the operation of line assembly system100will be discussed with regard toFIG.2. Assume, for this embodiment, that a layup mandrel120has proceeded along tracks110to a lamination machine150, but that the precise position and orientation (e.g., to a fraction of an inch and to the hundredth of a degree) of the layup mandrel120is not known. Thus, if the lamination machine150proceeds according to a “default” NC program and the layup mandrel120has even a slight deviation from nominal, laps or gaps may occur that are not within a desired tolerance, and the resulting laminate may have to be reworked.

FIG.2is a flowchart illustrating a method200for operating an indexing system based on the position of a roller162for a lamination head160in an illustrative embodiment. The steps of method200are described with reference to line assembly system100ofFIG.1, but those skilled in the art will appreciate that method200may 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.

Initially, a layup surface129of the layup mandrel120is identified202by controller112. The layup mandrel120travels in a process direction127during fabrication of a composite part. For example, the layup mandrel120may be periodically “micro pulsed” a predetermined distance in the process direction127over time (e.g., one foot every fifteen minutes, and/or pulsed the entire length of the layup mandrel120every two hours, etc.), or may be continuously moved in the process direction127at a predetermined rate (e.g., one inch per minute). The controller112may identify the layup surface129of the layup mandrel120based on preprogrammed information indicating an expected start position of first side surface122or second side surface124of the layup mandrel120, or may visually inspect the layup mandrel120to identify the first side surface122and/or second side surface124.

The controller112directs the lamination machine150to place204itself (i.e., via the roller162) in contact with first side surface122, or second side surface124. The lamination head160traverses206the first side surface122, or second side surface124with the roller162. During this process, the layup mandrel120remains in position. The roller162proceeds along a nominal path indicative of an expected position of the layup mandrel120along its length. As used herein, a “path” is a series of positions that may be measured and compared to a stream of 3D coordinates. If the layup mandrel120is not in an expected position and/or orientation, the roller162encounters physical resistance from the surface being traversed, and this physical resistance causes the roller162to deflect from the nominal path. These deflections are indicative of a surface geometry, such as contour, of the layup surface129, first side surface122, and second side surface124, and are recorded by the position sensor168.

In the next step, controller112acquires208a stream of three dimensional (3D) coordinates of the lamination head160(i.e. the roller162) as the lamination head160traverses the layup surface129. This may comprise acquiring a coordinate from the position sensor168periodically over time or space (e.g., every tenth of an inch, every tenth of a second, etc.), and storing the stream of coordinates in memory.

Continuing, the controller112characterizes210(e.g., determines an alignment and/or shape of the layup mandrel120to within a tolerance) based on the stream of 3D coordinates. This may be performed by loading a known shape of the layup mandrel120into memory, and applying a mathematical transform to a nominal alignment of the shape that causes the shape to match the stream of 3D coordinates. In further embodiments, the alignment of the layup mandrel120is more generally determined as either aligned or not aligned, based whether the stream of 3D coordinates is within a tolerance of the nominal path (e.g., a fraction of an inch of the nominal path).

Finally, the controller112alters212the NC program114that directs layup of fiber reinforced material at the layup mandrel120, based on a difference between the alignment of the layup mandrel120and a nominal alignment of the layup mandrel120. In one embodiment, this comprises applying a mathematical transform to coordinates found in instructions in the NC program114, based on a mathematical transform that was determined earlier. In a further embodiment, this comprises identifying locations in the NC program114that correspond with locations in the nominal path, and altering the locations in the NC program114by an amount equal to the differences detected from the nominal path in the stream of 3D coordinates. In yet another embodiment, the NC program114is altered in real time as needed to accommodate the laid down thickness of the laid down material already placed upon the layup mandrel120at a particular point during the layup process.

Method200provides a technical benefit over prior systems and techniques, because it enables a rigid tool125to be precisely indexed to a lamination machine150, without the need for additional indexing equipment of any kind. In particular, probes and other devices are not needed to perform indexing, and the lamination machine150is capable of adapting to changes from a nominal orientation, without having to re-orient a layup mandrel120. In an embodiment, the layup mandrel120may weigh hundreds or even thousands of pounds and would be difficult to re-orient as needed.

FIG.3is a perspective view of lamination head160traversing first side surface122of a layup mandrel120in an illustrative embodiment. According toFIG.3, the layup mandrel120proceeds in a process direction127, and includes first side surface122and second side surface124. The lamination head160will perform layup of fiber-reinforced material along layup region130between first side surface122and second side surface124, and is mounted to an extensible arm342(e.g., a robotic arm formed from a kinematic chain of rigid bodies and actuators, a telescopic arm, etc.) that moves laterally with respect to frame140as frame140moves along track110. The frame140moves backward372and forward374with respect to the process direction127along the tracks110and/or supports (not shown). The lamination head160inFIG.3is shown as performing an initial indexing operation by traversing the first side surface122and second side surface124, prior to initiating layup at the layup mandrel120. These operations may be performed during continuous motion of the layup mandrel120(e.g., at a slow rate of speed), or during pauses between pulses of the layup mandrel120in the process direction127. Furthermore, these operations could also occur during each micro pulse, pulse and/or layup operations may occur during pauses between micro pulses or pulses.

FIG.4is a top view of a rigid tool125(e.g., layup mandrel120) that is not within a nominal orientation in an illustrative embodiment, and corresponds with view arrows4of FIG.3. As shown inFIG.4, the layup mandrel120exhibits an angular offset θ from a nominal alignment400of less than one degree (the less than one degree offset is shown in exaggeration inFIG.4). However, the layup mandrel120has a length L (e.g., twenty-five feet, forty feet, etc.). This means that differences in position (Δ) accrue that result in deviations of region130from nominal layup region410, and these differences in position may exceed a desired tolerance. Hence, if a default NC program is utilized to lay up fiber reinforced material. Tows of fiber reinforced material result in out-of-tolerance conditions when not placed as desired, necessitating re-work of a laminate prior to or after curing.

FIG.5is a perspective view of a roller162traversing a surface500that varies with respect to an expected nominal path in an illustrative embodiment.FIG.5corresponds with view arrows5ofFIG.3. In this embodiment, a surface500includes variations from a nominal path510. As a lamination head160attempts to follow the nominal path with a roller162, the variations in the surface500enforce variations in position (Δx, Δy, and Δz) upon the roller162. A sensor (e.g., a sensor that measures positional offsets of components of a suspension that enable the roller162to deflect) measures these positional offsets for later comparison to a nominal path. In embodiments where the sensor is a rotary sensor that measures degrees of travel/rotation of the roller162, a larger radius R of the roller162may result in reduced precision of measurement. The radius R of the roller162may range from less than an inch to several inches. The sensor may measure these offsets to a fraction of an inch along each axis, and may do so at any suitable rate (e.g., kilohertz, megahertz, etc.). In one embodiment, an example of surface500is a first side surface122of layup mandrel120, and the lamination head160is further operated to traverse second side surface124of the layup mandrel120. In such a case, a controller112of the lamination head160acquires a second stream of 3D coordinates of the roller162as the roller162traverses the second surface.

FIG.6is a view of a roller162traversing a curved surface in an illustrative embodiment. According toFIG.6, a lamination head160traverses the surface602and the surface604of a layup mandrel120. By traversing two surfaces at different sides of the layup mandrel120, an orientation of the layup mandrel120along X, Y, and Z axes may be rapidly and precisely determined.

FIG.7is a view of a roller162traversing a laid-up laminate700in an illustrative embodiment. According toFIG.7, a position of the roller162as it follows a surface702defined by laminate700is actively tracked during layup to acquire a second stream of 3D coordinates. This information enables a thickness of a resulting laminate700to be determined, and this information (e.g., the second stream of 3D coordinates, along with any offset information that was previously determined) is passed to a downstream lamination machine1070having a downstream lamination head1072(e.g., as shown inFIG.11below) separated from the lamination head160by a distance D in the process direction127. The downstream lamination machine1070updates its own NC program using measurements from the lamination head160and/or downstream lamination head1072.

FIG.8is a view of a roller162traversing a laid-up laminate830that is laid-up around a tight radius in an illustrative embodiment. According toFIG.8, a roller162of a lamination head160traverses surfaces of layup mandrel120and/or laid-up laminate830within desired tolerances, such as surfaces that correspond with an outer radius of a corner833of a laminate830. This may be performed via multiple passes of the roller162at different arcuate portions of the curve832, and integrating the resulting sensor data to characterize the curve832along the length of the laminate830, which wraps around edge810and edge820of layup mandrel120. This operation may be performed after receiving laminate830from an upstream station, such as lamination machine150during layup, or after layup before the layup mandrel120proceeds to a downstream lamination machine1070. The information may then be utilized to alter an existing NC program114. For example, if the information indicates that a concave radius (not shown) is too small, additional layers may be applied to pad out the outer radius, or the lamination head160and NC program114are adjusted to account for the difference in geometry. Likewise, if the information indicates that a convex radius R1is too large, additional layers may be applied to pad out the outer radius to a desired R1, or the lamination head160and NC program114are adjusted to account for the difference in geometry.

FIG.9is a flowchart illustrating a method900for operating an indexing head170that traverses grooves126,128in a rigid tool125in an illustrative embodiment. According toFIG.9, method900includes identifying902a groove126that is within a rigid tool125(e.g., a layup mandrel120or other component). The groove126extends in a process direction127traveled by the rigid tool125during fabrication of a composite part, and may exhibit an eighth to a quarter inch or more of depth.

An indexing head170is placed904into the groove126. For example, the indexing head170may be pressed into the groove126at a desired level of pressure (e.g., twenty-five pounds per square inch). This physically unites an indexing end172of the indexing head170with the groove126, which means that if the groove126proceeds in an unexpected direction from a nominal path, it causes the indexing head170to deviate as well. The position of the indexing head170is measured by a sensor174over time. Hence, the deviations are capable of being determined by analyzing a stream of 3D coordinates from the sensor174.

The groove is traversed906via the indexing head170. That is, controller112operates the indexing head170to move along a nominal path. If the groove126deviates from the nominal path, it causes the indexing head170to deflect from its expected position.

A stream of 3D coordinates of the indexing head170is acquired908as the indexing head170traverses the groove126. Or in addition to or instead of the 3D coordinates, an arc and orientation of the arc of the indexing head170is acquired in908as the indexing head170traverses the groove126. This may comprise controller112sampling input from the sensor174at a desired rate (e.g., multiple times per second, multiple times per inch, etc.).

An alignment of the rigid tool125is determined in910based on the stream of 3D coordinates that was acquired in908. The determining910step may be performed in a similar manner to that of method200provided above.

A Numerical Control (NC) program114that directs work at the rigid tool125is altered in912, based on a difference between the alignment of the rigid tool125and a nominal alignment of the rigid tool125. The altering912step may be performed in a similar manner to the altering212step described above.

FIG.10is a perspective view of an indexing head170that follows one or more grooves126and128in a rigid tool125in order to index the rigid tool125having a layup region130in an illustrative embodiment. The groove126follows a series of non-repeating curves1026. In this embodiment, indexing head170moves perpendicular to the process direction127along frame140, and frame140moves parallel to the process direction127along tracks110. The rigid tool125proceeds downstream in the process direction127to downstream lamination machine1070having a lamination head1072(i.e., a second, or downstream, lamination head). In this embodiment, the downstream lamination machine1070is separated from the upstream lamination machine150by a distance D (FIG.11) in the process direction127.

As shown inFIG.10, each of the grooves126,128may exhibit a unique series of non-repeating curves. Hence, each location along the groove126,128is uniquely identifiable based on curvature information. By analyzing changes in position of the stream of 3D coordinates, an exact position along the rigid tool125may therefore be determined (e.g., to the inch, to a fraction of an inch, etc.). In embodiments wherein the grooves126,128are each unique, the exact groove126,128being traversed may also be determined, based on the curvature of the groove126,128. In further embodiments, features of the groove126,128are used to communicate information. This information may include width, depth, angle, or slope of the groove walls, or a cross sectional shape such as a triangular, square, rectangular or half circle shape, or an ellipse. This information may further include varying the cross-sectional shape along the groove126,128, placing notches or splines along the walls of the groove126,128, or applying magnetic fields with strength that varies down the groove126,128, etc. This information may be used to indicate specific regions along the length of each groove126,128.

FIG.11is a top view of an indexing head170that follows a groove126,128in a rigid tool125in order to index the rigid tool125in an illustrative embodiment, and corresponds with view arrows11ofFIG.10. According toFIG.11, each of the grooves126and128exhibits a unique, non-repeating series of curves. The rollers162discussed herein may be made from rigid materials that do not scratch or damage the underlying rigid tool125. As the rigid tool125may be made from steel or other metals, the rollers162may be made, for example, from high-density polyurethane.

FIGS.12-14are front views of different rollers for indexing heads170that traverse grooves in rigid tools in illustrative embodiments, and correspond with view arrows12ofFIG.11. Specifically,FIG.12illustrates a roller1210having a triangular notch1212for rolling within a triangular groove1200,FIG.13illustrates a roller1310having a rectangular notch1312for rolling within a rectangular groove1300, andFIG.14illustrates a roller1410with a roller ball1420having a semicircular notch1412for traversing a semicircular groove1400.

FIG.15is a cut-through view of an indexing head1500having a roller1510carried by a suspension1502in an illustrative embodiment, and corresponds with view arrows15ofFIG.11. The roller1510includes a notch1512that is triangular in cross-section (corresponding to roller1210) and continues along the curvature of the roller1510, for rolling along a triangular groove. Roller1310and roller1410are capable of replacing roller1510if needed to match rectangular groove1300or semicircular groove1400, respectively. The roller1510rotates about a bar1520, and linear travel of the roller1510is measured by rotational sensors1530. Suspension cylinders1540and1550(and additional suspension cylinders along an additional axis proceeding into the page) absorb deviations in position caused by the groove when the groove does not follow a nominal path, and these deviations may then be measured by a position sensor. In further embodiments, contours126-1and128-1(FIG.11) are added to the groove or groove surface to convey additional information to different stations. In further embodiments, multiple grooves126and/or128are added to the rigid tool125to convey additional information to different stations, such as lamination machine150and downstream lamination machine1070. For example, each groove may be utilized by a different station for different indexing purposes to conform with different sets of constraints. The information being conveyed by the grooves126and128include, but are not limited to layup patterns, ramp rates, ply orientations and other ply or laminate specifics. Additional embodiments have portions of the grooves126and128aimed at conveying information only to lamination machine150and other portions aimed conveying information only to downstream lamination machine1070.

FIG.16is a flowchart illustrating a method1600for operating an indexing head1710that traverses a circumferential groove1704in an arcuate tool1700in an illustrative embodiment. The operations of method1600are described with regard to the system depicted inFIG.17and includes identifying1602an arcuate tool1700that travels in a process direction127during fabrication of a composite part. Method1600is similar to method900ofFIG.9provided above, except that the grooves1702,1704proceed circumferentially with respect to arcuate tool1700.

A groove1704is identified1604within the arcuate tool1700that extends along a portion of the arcuate tool1700. An embodiment has groove1704is identified1604within the arcuate tool1700that extends along an arcuate portion of the arcuate tool1700. This may comprise utilizing a camera to detect a position of a groove1704at the arcuate tool1700, placing1606an indexing end1712of an indexing head1710over the groove1704, or placing1606the indexing head1710at a location where the groove1704will mate with the indexing end1712when the arcuate tool1700travels in the process direction127.

As mentioned, an indexing end1712is placed1606into the groove1704. This may further include placing1606an indexing end1722of a second indexing head1720into a second groove1702. In such an embodiment, the indexing head1710is downstream of the second indexing head1720, and a lamination machine1730is disposed between the indexing heads1710,1720.

The arcuate tool1700is rotated1608relative to the indexing head1710such that the indexing end1712traverses the groove1704. In one embodiment, this comprises rotating the arcuate tool1700about its central axis or via a rotatable support1750(held by a frame1752) that is configured to retain the arcuate tool1700, and that is configured to rotate the arcuate tool1700relative to the indexing head1710such that the indexing end1712traverses the groove1704. In a further embodiment, this comprises moving the indexing heads1710and1720circumferentially about the arcuate tool1700. In embodiments where the arcuate tool1700is moved continuously in the process direction127, the indexing heads1710and1720match the speed of the arcuate tool1700to remain in position with respect to the arcuate tool1700as the arcuate tool1700moves.

A stream of 3D coordinates of the indexing head1710,1720is acquired1610as the indexing head1710,1720traverses the respective groove1704,1702. This input is acquired from positional sensors (not shown inFIG.17but similar to sensors168shown inFIG.1) at the indexing heads1710,1720. In one embodiment, a single indexing head traverses multiple grooves of the arcuate tool1700(i.e., by traversing first groove1704over a first period of time, and by traversing second groove1702over a second period of time). This results in multiple streams of 3D coordinates for analysis.

An alignment of the arcuate tool1700is determined1612based on the stream of 3D coordinates. This may be performed in a similar manner to the characterizing210step of method200discussed above. A Numerical Control (NC) program114that directs work at the arcuate tool1700is altered1614, based on a difference between the alignment of the arcuate tool1700and a nominal alignment of the arcuate tool1700as represented by 3D coordinates associated with the nominal path. This may be performed in a similar manner to the altering212step of method200discussed above.

With the NC program114adjusted, the lamination machine1730proceeds to operate its lamination head1732to lay up one or more tows1740for a laminate. The laminate is then hardened into a composite part, such as a half-barrel section of an aircraft fuselage.

Method1600may be particularly valuable in environments wherein a heavy arcuate tool1700(e.g., weighing multiple tons) is held at one end by rotatable support1750. In such circumstances, a weight of the arcuate tool1700causes a minor deflection/angular deviation along the length of the arcuate tool1700.

In still further embodiments, grooves126,128,1702,1704comprise continuous protrusions from rigid tool125, arcuate tool1700that are mated to indexing heads170,1710,1720that have pairs of rollers (e.g., one roller on either side of the protrusion). In yet further embodiments, the grooves126,128,1702,1704are not physical grooves, but rather are painted or colored lines that are tracked by sensors in the form of high-precision cameras. The sensors may further comprise distancing sensors such as laser or ultrasonic sensors that track across the rigid tool125, arcuate tool1700while measuring distance. Thus, indexing may be performed based on imaging from sensors that follow visually distinct patterns at rigid tools, without actually contacting those rigid tools and particularly by indexing head1500.

FIG.18is an example report1800indicating a difference between a nominal position and actual position of one of the indexing heads described herein in an illustrative embodiment. The report comprises a stream of 3D coordinates acquired over time. For each measured 3D coordinate, the controller compares the coordinate to an expected 3D coordinate, and calculates a difference between the measured 3D coordinate and the expected 3D coordinate. The controller then alters instructions in an NC program for performing work (e.g., layup) at the rigid tool being indexed, by identifying positions indicated in the instructions, and applying corresponding differences in position to the instructions.

EXAMPLES

Referring more particularly to the drawings, embodiments of the disclosure may be described in the context of aircraft manufacturing and service in method1900as shown inFIG.19and an aircraft1902as shown inFIG.20. During pre-production, method1900may include specification and design1904of the aircraft1902and material procurement1906. During production, component and subassembly manufacturing1908and system integration1910of the aircraft1902takes place. Thereafter, the aircraft1902may go through certification and delivery1912in order to be placed in service1914. While in service by a customer, the aircraft1902is scheduled for routine work in maintenance and service1916(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 method1900(e.g., specification and design1904, material procurement1906, component and subassembly manufacturing1908, system integration1910, certification and delivery1912, service1914, maintenance and service1919) and/or any suitable component of aircraft1902(e.g., airframe1918, systems1920, interior1922, propulsion system1924, electrical system1926, hydraulic system1928, environmental system1930).

Each of the processes of method1900may be performed or carried out by a system integrator, a third party, and/or an operator (e.g., a customer). For the purposes of this description, a system integrator may include without limitation any number of aircraft manufacturers and major-system subcontractors; a third party may include without limitation any number of vendors, subcontractors, and suppliers; and an operator may be an airline, leasing company, military entity, service organization, and so on.

As shown inFIG.20, the aircraft1902produced by method1900may include an airframe1918with a plurality of systems1920and an interior1922. Examples of systems1920include one or more of a propulsion system1924, an electrical system1926, a hydraulic system1928, and an environmental system1930. Any number of other systems may be included. Although an aerospace example is shown, the principles of the invention 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 method1900. For example, components or subassemblies corresponding to component and subassembly manufacturing1908may be fabricated or manufactured in a manner similar to components or subassemblies produced while the aircraft1902is in service. Also, one or more apparatus embodiments, method embodiments, or a combination thereof may be utilized during the subassembly manufacturing1908and system integration1910, for example, by substantially expediting assembly of or reducing the cost of an aircraft1902. Similarly, one or more of apparatus embodiments, method embodiments, or a combination thereof may be utilized while the aircraft1902is in service, for example and without limitation during the maintenance and service1916. Thus, the invention may be used in any stages discussed herein, or any combination thereof, such as specification and design1904, material procurement1906, component and subassembly manufacturing1908, system integration1910, certification and delivery1912, service1914, maintenance and service1916and/or any suitable component of aircraft1902(e.g., airframe1918, systems1920, interior1922, propulsion system1924, electrical system1926, hydraulic system1928, and/or environmental system1930.

In one embodiment, a part comprises a portion of airframe1918, and is manufactured during component and subassembly manufacturing1908. The part may then be assembled into an aircraft in system integration1910, and then be utilized in service1914until wear renders the part unusable. Then, in maintenance and service1916, the part may be discarded and replaced with a newly manufactured part. Inventive components and methods may be utilized throughout component and subassembly manufacturing1908in order to manufacture new parts.

Any of the various control elements (e.g., electrical or electronic components) shown in the figures or described herein may be implemented as hardware, a processor implementing software, a processor implementing firmware, or some combination of these. For example, an element may be implemented as dedicated hardware. Dedicated hardware elements may be referred to as “processors”, “controllers”, or some similar terminology. When provided by a processor, the functions may be provided by a single dedicated processor, by a single shared processor, or by a plurality of individual processors, some of which may be shared. Moreover, explicit use of the term “processor” or “controller” should not be construed to refer exclusively to hardware capable of executing software, and may implicitly include, without limitation, digital signal processor (DSP) hardware, a network processor, application specific integrated circuit (ASIC) or other circuitry, field programmable gate array (FPGA), read only memory (ROM) for storing software, random access memory (RAM), non-volatile storage, logic, or some other physical hardware component or module.

Also, a control element may be implemented as instructions executable by a processor or a computer to perform the functions of the element. Some examples of instructions are software, program code, and firmware. The instructions are operational when executed by the processor to direct the processor to perform the functions of the element. The instructions may be stored on storage devices that are readable by the processor. Some examples of the storage devices are digital or solid-state memories, magnetic storage media such as a magnetic disks and magnetic tapes, hard drives, or optically readable digital data storage media.

Although specific embodiments are described herein, the scope of the disclosure is not limited to those specific embodiments. The scope of the disclosure is defined by the following claims and any equivalents thereof.