Abstract:
Techniques of performing a manufacturing operation on a workpiece are disclosed. In one embodiment, a method includes forming an indexing hole in the workpiece. A coordinating pin may be installed into the indexing hole, the coordinating pin including a quantum of indexing information. A sensor may be positioned proximate the coordinating pin. The quantum of indexing information may be sensed with a sensor. A manufacturing operation may be performed on the workpiece based at least partially on the quantum of indexing information.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    This patent application is a divisional application of co-pending, commonly-owned U.S. patent application Ser. No. 10/903,713 entitled “Apparatus and Methods for Manufacturing Operations” filed on Jul. 30, 2004, which claims priority from U.S. Provisional Application Ser. No. 60/500,863, filed Sep. 5, 2003, which applications are incorporated herein by reference. 
     
    
     TECHNICAL FIELD 
       [0002]    The present disclosure relates to apparatus and methods for manufacturing operations, and more specifically, to manufacturing operations employing vacuum devices, and to manufacturing operations that employ an indexing system based on pin locations. 
       BACKGROUND 
       [0003]    Manufacturing operations in many fields typically require accurate positioning of manufacturing tools over a workpiece. The manufacturing environment and the structural details of the workpiece often make it difficult to properly position the manufacturing tool relative to the workpiece to achieve the desired manufacturing operation with the necessary degree of accuracy. This is particularly true in the field of aircraft manufacturing, wherein a large number of manufacturing operations are typically needed on a variety of contoured surfaces. Similar difficulties may be encountered, for example, in the manufacture of ships, railcars, missiles, sheet metal buildings, and other similar structures. 
         [0004]    It is known that a support assembly that supports a manufacturing tool may be temporarily attached to a surface of the workpiece in order to facilitate manufacturing operations on the workpiece. Some conventional support assemblies utilize one or more elongated rails equipped with vacuum cup assemblies for temporarily attaching the support assembly to the workpiece, including, for example, those assemblies generally disclosed in U.S. Pat. No. 6,467,385 B1 issued to Buttrick et al., and U.S. Pat. No. 6,210,084 B1 issued to Banks et al. In such conventional support assemblies, the rails may be coupled to the workpiece using the vacuum cup assemblies over a desired section of the workpiece, and then a manufacturing tool may be mounted on a carriage that is moveable along the rails. The carriage may then be traversed along the rails in a manual or automated fashion, and the desired manufacturing operations may be performed. 
         [0005]    Vacuum for the vacuum cup assemblies of such conventional support assemblies is typically generated externally from the point-of-use, such as by a vacuum pump or other suitable source. The vacuum is then routed to each vacuum cup assembly by one or more vacuum lines. In order to isolate one vacuum circuit from another it is usually necessary to run separate, multiple lines to each vacuum cup assembly, or incorporate a valve network to isolate one line from another. Because the pressure differential along the length of each vacuum line is at most one atmosphere, care must be taken to avoid line losses which may degrade the degree of vacuum provided to the vacuum cup assemblies. One conventional approach to solving this line-loss problem is to provide a portable vacuum pump that may be transported along with the vacuum assembly in order to reduce the lengths of the vacuum lines between the vacuum pump and the vacuum cup assemblies. 
         [0006]    Traditional hard tooling and indexing systems for large-scale manufacturing operations typically involve the construction of large, “monument like” equipment that provides support and indexing during manufacturing operations on a workpiece. Such structures are typically very expensive to design, build, and maintain. For example, the tooling for a new airplane manufacturing operation may comprise a substantial percentage of the initial investment cost of the manufacturing facilities needed to produce the aircraft. 
         [0007]    Although desirable results have been achieved using the prior art manufacturing methods and apparatus, there is still room for improvement. Namely, it may yet be possible to improve the operating efficiency, cost, and performance of such manufacturing operations. 
       SUMMARY 
       [0008]    The present disclosure is directed to methods for manufacturing operations, and more specifically, to manufacturing operations employing vacuum devices, and to manufacturing operations that employ an indexing system based on pin locations. Methods in accordance with the present disclosure may advantageously improve the efficiency, throughput, and accuracy of manufacturing operations on a workpiece. 
         [0009]    In one embodiment, a method includes forming an indexing hole in the workpiece. A coordinating pin may be installed into the indexing hole, the coordinating pin including a quantum of indexing information. A sensor may be positioned proximate the coordinating pin. The quantum of indexing information may be sensed with a sensor. A manufacturing operation may be performed on the workpiece based at least partially on the quantum of indexing information. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0010]    The preferred and alternative embodiments of the present disclosure are described in detail below with reference to the following drawings. 
           [0011]      FIG. 1  is an upper isometric view of a vacuum support assembly having a plurality of vacuum cup assemblies in accordance with an embodiment of the disclosure; 
           [0012]      FIG. 2  is a lower isometric view of the vacuum support assembly of  FIG. 1 ; 
           [0013]      FIG. 3  is an upper isometric, partial cross-sectional view of a vacuum cup assembly in accordance with an embodiment of the disclosure; 
           [0014]      FIG. 4  is a top elevational view of a retaining plate and a sealing member of the vacuum cup assembly of  FIG. 3 ; 
           [0015]      FIG. 5  is a bottom elevational view of the retaining plate and the sealing member of  FIG. 4 ; 
           [0016]      FIGS. 6A-D  show partial cross-sectional views of the retaining plate and the sealing member of  FIG. 4 ; 
           [0017]      FIG. 7  is a top elevational view of a retaining plate of the vacuum cup assembly of  FIG. 4 ; 
           [0018]      FIG. 8  is a lower isometric view of a rail assembly including a plurality of vacuum cup assemblies in accordance with an alternate embodiment of the disclosure; 
           [0019]      FIG. 9  is a schematic view of a first hole pattern in a rail member in accordance with an embodiment of the disclosure; 
           [0020]      FIG. 10  is a schematic view of a second hole pattern in a rail member in accordance with an embodiment of the disclosure; 
           [0021]      FIG. 11  is an upper isometric view of a rail assembly including a plurality of vacuum cup assemblies in accordance with another embodiment of the disclosure; 
           [0022]      FIG. 12  is an isometric view of a vacuum generator of  FIG. 11 ; 
           [0023]      FIG. 13  is an isometric view of a representative manufacturing assembly in accordance with yet another embodiment of the disclosure; 
           [0024]      FIG. 14  is a flow chart of a first portion of a manufacturing process in accordance with an embodiment of the disclosure; 
           [0025]      FIG. 15  is a flow chart of a second portion of a manufacturing process in accordance with an embodiment of the disclosure; 
           [0026]      FIG. 16  is an isometric view of a manufacturing operation in accordance with yet another embodiment of the disclosure; and 
           [0027]      FIGS. 16A ,  16 B and  17 A- 17 D show enlarged, partial cross-sectional and end elevational views of a coordinate pin of  FIG. 16 , and a coordinate pin reader, in accordance with another embodiment of the disclosure. 
       
    
    
     DETAILED DESCRIPTION 
       [0028]    The present disclosure relates to apparatus and methods for manufacturing operations, and more specifically, to manufacturing operations employing vacuum devices, and to manufacturing operations that employ an indexing system based on pin locations. Many specific details of certain embodiments of the disclosure are set forth in the following description and in  FIGS. 1-17  to provide a thorough understanding of such embodiments. One skilled in the art, however, will understand that the present disclosure may have additional embodiments, or that the present disclosure may be practiced without several of the details described in the following description. 
         [0029]      FIGS. 1 and 2  are upper and lower isometric views, respectively, of a vacuum support assembly  100  having a plurality of vacuum cup assemblies  110  in accordance with an embodiment of the disclosure. In this embodiment, the vacuum support assembly  100  includes a rack  102  to which the vacuum cup assemblies  110  are attached. An intake manifold  104  having an intake port  106  is mounted at a first end of the rack  102 . A cover (or muffler)  107  extends along the length of the rack  102 , as described more fully below. An air supply line  108  extends from the manifold  104  to one or more of the vacuum cup assemblies  110 . Similarly, vacuum lines  109  extend between adjacent vacuum cup assemblies  110 . 
         [0030]      FIG. 3  is an upper isometric, partial cross-sectional view of a vacuum cup assembly  110  in accordance with an embodiment of the disclosure. In this embodiment, the vacuum cup assembly  110  includes a vacuum generator  112  having a housing  114  with a retaining plate  116  coupled to a sealing member  118 . The housing  114  includes a pair of tube clips  120  extending from opposing ends thereof, and a plurality of attachment holes  124  (four shown) are disposed in the housing  114  to facilitate the attachment of the housing  114  to the rack  102  (e.g. by bolts or other suitable attachment members). An air supply port  122  is disposed in the housing  114  and is fluidly coupled to a high pressure portion  132  of an internal flow duct  134  (shown in phantom lines) disposed through the housing  114 . In this embodiment, the high pressure portion  132  of the internal flow duct  134  leads to a venturi portion  136 , and then to a low pressure portion  138 . Finally, the internal flow duct  134  exits the housing  114  at a pair of exhaust ports  131  (shown in phantom lines). The housing  114  includes a pair of outwardly-depending exhaust mufflers  126  that at least partially shroud the air exhaust ports  131 . Finally, an auxiliary vacuum port  128  is disposed in the housing  114  and is coupled by an auxiliary flow duct  140  (shown in phantom lines) to the low pressure portion  138  of the internal flow duct  114 . 
         [0031]    It will be appreciated that any suitable fluid medium may be used to operate the vacuum cup assemblies  110 , and that the present disclosure is not limited to air as the operating fluid medium. For the sake of simplicity, however, throughout the following description, the term air will be used to refer to the operating fluid medium. 
         [0032]      FIGS. 4 and 5  are top and bottom elevational views, respectively, of the retaining plate  116  and the sealing member  118  of the vacuum cup assembly  110  of  FIG. 3 .  FIG. 6  shows various partial cross-sectional views of the retaining plate  116  and the sealing member  118  of  FIG. 4 .  FIG. 7  is a top elevational view of the retaining plate  116  of  FIG. 4 . As best shown in  FIGS. 5 and 7 , a plurality of coupling apertures  130  are disposed through the retaining plate  116  for coupling the retaining plate  116  (and the sealing member  118 ) to the housing  114  using fasteners (not shown). 
         [0033]    In operation, a source of pressurized air is coupled to the intake port  106  of the vacuum support assembly  110 . The pressurized air passed into the intake manifold  104  and then through the air line  108  to one or more of the vacuum cup assemblies  110 . At the vacuum cup assembly  110 , the pressurized air enters the air supply port  122  of the vacuum generator  112  (see arrow A) and passes through the high pressure portion  132  (see arrow B) of the internal flow duct  134 . The pressurize air then expands through the venturi portion  136  and into the low pressure portion  138  (see arrow C) of the internal flow duct  134 . The expanded air is exhausted from the internal flow duct  134  via the exhaust ports  130  (see arrows D) into the surrounding environment. 
         [0034]    As best shown in  FIG. 2 , one or more vacuum ports  142  are disposed in a bottom surface  144  of the vacuum generator  112  and provide fluid communication between the low pressure portion  138  of the internal flow duct  134  and a suction chamber  146  formed between the vacuum cup assembly  110  and a workpiece  148  (see  FIG. 3 ). As the pressurized air is expanded through the venturi portion  136 , the low pressure portion  138 , the exhaust ducts  130 , and the suction chamber  146  formed between the vacuum cup assembly  110  and the workpiece  148  is exhausted (i.e. the pressure within the suction chamber  146  drops). As shown in  FIG. 6 , the sealing member  118  is flexible and bends from an initial non-deflected position  150  ( FIG. 6(B) ) prior to the reduction of pressure within the suction chamber  146 , to a deflected position  152  ( FIG. 6(C) ) substantially in alignment with a foot  119  as the pressure within the suction chamber  146  is reduced and the vacuum cup assembly  110  is drawn closer to the workpiece  148 . Thus, the plurality of vacuum cup assemblies  110  adhere to the workpiece  148  and support the vacuum support assembly  100  in a desired position on the workpiece  148 . 
         [0035]    It will be appreciated that a variety of different vacuum generator  112  configurations may be conceived, and that the vacuum generator is not limited to the particular configuration described above and shown in the accompanying figures. It will also be appreciated that the vacuum generator may be at least partially fabricated from known, conventional vacuum generators  112 , including, for example, those vacuum generators offered as model number X5 vacuum generators by PIAB, Inc. of Hingham, Mass. 
         [0036]    The vacuum cup assemblies  110  may provide several advantages over prior art vacuum cup assemblies. For example, because the vacuum cup assemblies  110  rely on pressurized air which is used to form the necessary pressure drop within the suction chamber  146  locally at each vacuum cup assembly  110 , the vacuum support assembly  100  is far less sensitive to pressure losses than prior art assemblies. In contrast to such prior art assemblies, in which the maximum pressure differential along a vacuum line leading from a vacuum source to each vacuum cup assembly is one atmosphere (at most), in the vacuum support apparatus  100 , the pressure differential along the air lines  108  leading to the vacuum cup assemblies  110  can be far greater than one atmosphere. Thus, the energy that can be transferred from the point of generation to the point of use though a given size of tube is far greater in embodiments of the present disclosure than in prior art assemblies. As a result, in positive pressure systems in accordance with the present disclosure, because the necessary vacuum can be generated at the vacuum cup assembly more efficiently than in the prior art vacuum-based systems, the apparatus in accordance with the present disclosure may operate more efficiently than comparable prior art systems. Also, because of the improved operational efficiencies, embodiments of the present disclosure may utilize relatively smaller, less bulky components (e.g. smaller diameter tubes), enabling vacuum support assemblies  100  in accordance with the present disclosure to be used in a wider variety of applications. 
         [0037]    Furthermore, embodiments of vacuum support assemblies may be more robust and reliable in comparison with alternate, prior art vacuum support assemblies. Since the vacuum cup assemblies rely on pressurized air, and since the pressure differential within the air supply system for the pressurized air may greatly exceed one atmosphere, embodiments of the present disclosure may be far less sensitive to leakage and failure of a particular system component (e.g. a sealing member of a vacuum cup assembly). Thus, even in the event that one vacuum usage point (e.g. a vacuum cup assembly) becomes disabled, the reduced pressures within the suction chambers of the other vacuum cup assemblies  110  may remain relatively unaffected, and the vacuum support assembly  100  may continue to operate. 
         [0038]    In addition, embodiments of the present disclosure advantageously eliminate the need for portable vacuum sources to accompany the vacuum support assembly, relying instead on more commonly-available sources of pressurized air. Thus, embodiments of the present disclosure may provide improved accessibility and ease of use in comparison with alternate, prior art assemblies. 
         [0039]    It will be appreciated that a wide variety of support assemblies and manufacturing assemblies may be conceived that incorporate embodiments of apparatus in accordance with the present disclosure. Some embodiments of the present disclosure may advantageously use an integrated assembly of a vacuum cup, vacuum pump/generator, manifold, muffler and mounting system all-in-one. In alternate embodiments, this may be accomplished by using, for example, off-the-shelf components integrated into a common housing, or the generator and muffler may be physically fabricated into the backshell/housing of the vacuum cup. This compact and common design can easily be mounted and plumbed in many different configurations for various applications. In further embodiments, two or more vacuum cup assemblies  110  can share common a vacuum generator  112  and/or supply pressure line  108  to improve reliability, reduced flow requirements, assembly time and tubing lines. 
         [0040]    For example, one possible embodiment is shown in  FIG. 8 , which provides a lower isometric view of a rail assembly  200  including a plurality of vacuum cup assemblies  110  in accordance with an alternate embodiment of the disclosure. In this embodiment, the rail assembly  200  includes a rail member  202  having first and second edges  204 ,  206 . As described, for example, in the above-referenced U.S. Pat. No. 6,467,385 B1 issued to Buttrick et al., and U.S. Pat. No. 6,210,084 B1 issued to Banks et al., which patents are incorporated herein by reference, a manufacturing tool may be operatively coupled to at least one of the first and second edges  204 ,  206  of the rail member  202  for performing manufacturing operations on the workpiece  148 . 
         [0041]    With continue reference to  FIG. 8 , the plurality of vacuum cup assemblies  110  are coupled directly to a lower surface  208  of the rail member  202  by fasteners  212  passing through the coupling apertures  130  ( FIG. 7 ). The air lines  108  may extend along an upper surface  214  (not visible in  FIG. 8 ) of the rail member  202 , and may provide the necessary flow of pressurized air to the vacuum generators  112  of the vacuum cup assemblies  110  via air holes formed in the rail member  202 .  FIGS. 9 and 10  are schematic views of first and second hole patterns  216 ,  218 , respectively, that may be formed in the rail member  202  for this purpose. Thus, the above-described advantages of embodiments of the present disclosure may be achieved in a rail assembly  200  as shown in  FIGS. 8 through 10 . 
         [0042]      FIG. 11  is an upper isometric view of a rail assembly  300  including a plurality of vacuum cup assemblies  310  in accordance with another embodiment of the disclosure. In this embodiment, the vacuum cup assemblies  310  are coupled to a lower surface  308  of a rail member  302 , and a vacuum generator  312  is disposed between and operatively coupled to a pair of adjacent vacuum cup assemblies  310 . The air line  108  is coupled to the vacuum generator  312  and extends along the lower surface  308  of the rail member  302  (i.e. the same surface upon which the vacuum cup assemblies  310  are attached), thereby advantageously leaving the upper surface free from obstructions to facilitate the movement of manufacturing tools or carriage assemblies along the upper surface of the rail member  302 . 
         [0043]      FIG. 12  is an isometric view of the vacuum generator  312  of  FIG. 11 . In this embodiment, the air line  108  is coupled to the intake port  306  so that pressurized air passes through the internal flow duct  334  disposed within the housing  314 . A pair of vacuum ports  328  are fluidly coupled to the internal flow duct  334  (e.g. to the venturi portion  336  or the low pressure portion  338 ), and are in turn coupled to vacuum lines  329  which lead to the suction chamber  346  of each of the adjacent vacuum cup assemblies  310 . As in the embodiment described above, the pressurized air exits the internal flow duct  334  via the exhaust apertures  330 , which are at least partially shrouded by the shrouds  336 . The above-noted advantages of embodiments of the present disclosure may thereby be achieved in a rail assembly  300  wherein a single vacuum generator  312  creates a reduced pressure (or vacuum) for a pair of adjacent vacuum assemblies as shown in  FIGS. 11 and 12 . 
         [0044]    It will be appreciated that various additional embodiments of manufacturing apparatus incorporating one or more aspects of the present disclosure may be conceived in accordance with the present disclosure. Such apparatus may range from automated, computer controlled manufacturing apparatus, to relatively-simple manually-operated apparatus, and even to relatively simple, manually-driven apparatus. Representative manufacturing assemblies which may incorporate apparatus in accordance with the present disclosure include, but are not limited to, those manufacturing assemblies generally described in U.S. Pat. No. 4,850,763 issued to Jack et al., as well as the exemplary manufacturing assemblies disclosed in co-pending, commonly owned U.S. patent application Ser. No. 10/016,524 entitled “Flexible Track Drilling Machine” filed Dec. 10, 2001, co-pending, commonly-owned U.S. patent application Ser. No. 10/606,402 entitled “Apparatus and Methods for Servo-Controlled Manufacturing Operations” filed Jun. 25, 2003, co-pending, commonly-owned U.S. patent application Ser. No. 10/606,443 entitled “Methods and Apparatus for Counter-Balance Assisted Manufacturing Operations” filed Jun. 25, 2003, co-pending, commonly-owned U.S. patent application Ser. No. 10/606,472 entitled “Methods and Apparatus for Manufacturing Operations Using Opposing-Force Support Systems” filed Jun. 25, 2003, and co-pending, commonly-owned U.S. patent application Ser. No. 10/606,473 entitled “Apparatus and Methods for Manufacturing Operations Using Non-Contact Position Sensing” filed Jun. 25, 2003, which patents and patent applications are hereby incorporated by reference. 
         [0045]      FIG. 13  is an isometric view of a representative manufacturing assembly  400  in accordance with yet another embodiment of the disclosure. In this embodiment, the manufacturing assembly  400  includes a track assembly  410  controllably attachable to a workpiece  130 , and a carriage assembly  420  moveably coupled to the track assembly  410 . A secondary controller  430  is mounted on the carriage assembly  420  and is operatively coupled to a primary controller  434 . At least one of the secondary controller  430  and the primary controller  434  may also be coupled to a manufacturing tool  451  mounted on the carriage assembly  420 . 
         [0046]    As further shown in  FIG. 13 , the track assembly  410  may include first and second rails  422 ,  424 , each rail  422 ,  424  being equipped with a plurality of vacuum cup assemblies  414  in accordance with one or more embodiments of the present disclosure. The vacuum cup assemblies  414  are fluidly coupled to a supply line  416  leading to a source of pressurized fluid  418 , such as a pump or the like, such that a reduced pressure may be formed in the suction chambers of the vacuum cup assemblies  414  as described above to secure the track assembly  410  to the workpiece  480 . 
         [0047]    The rails  422 ,  424  may be connected by one or more connecting members  428 , and may be adapted to bend, twist, and flex to adjust to the contours of the workpiece  130 . The carriage assembly  420  may translate along the rails  422 ,  424  by virtue of rollers  432  that are mounted on an x-axis carriage  460  of the carriage assembly  420  and engaged with the rails  422 ,  424 . In a particular embodiment, each rail  422 ,  424  may have a V-shaped edge engaged by the rollers  32 , and the rollers  32  may include V-shaped grooves that receive the V-shaped edges of the rails  422 ,  424 . In another embodiment, the x-axis carriage  460  may be adapted to flex and twist as needed (i.e. as dictated by the contour of the workpiece  130 ) as the carriage assembly  420  traverses the rails  422 ,  422  to allow a limited degree of relative movement to occur between the x-axis carriage  430  and the rollers  432 . Consequently, a reference axis of the carriage assembly  420  (in the illustrated embodiment, a z-axis normal to the plane of the x-axis carriage  460 ) may be maintained substantially normal to the workpiece  130  at any position of the carriage assembly  420  along the rails  422 ,  424 . 
         [0048]    As further shown in  FIG. 13 , a rack  438  for a rack and pinion arrangement is mounted along the rail  424 . A first motor  440  and associated first gearbox  442  is mounted on the carriage assembly  420 . An output shaft from the first gearbox  442  has a first pinion gear  444  mounted thereon which engages the rack  438  on the rail  424 . Thus, rotation of the first pinion gear  444  by the first motor  440  drives the carriage assembly  420  along the rails  422 ,  424 . 
         [0049]    With continued reference to  FIG. 13 , the carriage assembly  420  further includes a y-axis carriage  450  slideably mounted atop the x-axis carriage  460  so that the y-axis carriage  450  can slide back and forth along a y-axis direction perpendicular to the x-axis direction. More particularly, rails  452 ,  454  are affixed to the opposite edges of the x-axis carriage  460 , and rollers  456  are mounted on the y-axis carriage  450  for engaging the rails  452 ,  454 . A rack  458  for a rack and pinion arrangement is affixed to the x-axis carriage  460  along the rail  454 . A second motor  480  and associated second gearbox  482  are mounted on the y-axis carriage  450  and drive a second pinion gear (not shown) that engages the rack  458  to drive the y-axis carriage  450  in the y-axis direction. Additional aspects of the manufacturing assembly  400  are described in the above-referenced co-pending, commonly owned U.S. patent application Ser. No. 10/016,524 entitled “Flexible Track Drilling Machine” filed Dec. 10, 2001, previously incorporated by reference herein. 
         [0050]    In operation, the manufacturing assembly  400  may be mounted onto the workpiece  130  by providing a flow of pressurized fluid medium from the source  418  to the vacuum cup assemblies  414  in a manner as described above. The carriage assembly  420  may then be moved to a desired position over the workpiece  130 . Specifically, at least one of the primary and secondary controllers  434 ,  430  may transmit control signals to the first drive motor  440  to drive the carriage assembly  420  along the track assembly  410 , and may also transmit control signals to the second drive motor  480  to adjust the position of the y-axis carriage  450  be coupled to the carriage assembly  420  by, for example, a clamp ring  470  or other suitable structure that provides access to the workpiece  130  for the manufacturing tool  451 . 
         [0051]    It should also be understood that the various operations of the manufacturing assembly  400  may be accomplished in an automated or semi-automated manner using computerized numerically-controlled (CNC) methods and algorithms. Alternately, the various operations of the manufacturing assembly  400  may be performed manually or partially-manually by an operator, such as, for example, by having the operator provide manual control inputs to the primary and/or secondary controllers  434 ,  430 , or by temporarily disabling or neutralizing the above-referenced motors and drive assemblies to permit manual movement. In a particular aspect, at least one of the primary and secondary controllers  434 ,  430  includes a CNC control system. It may also be noted that manufacturing assemblies in accordance with the present disclosure, including the manufacturing assembly  400  described above, may be operated in combination with a wide variety of manufacturing tools  451 , including but not limited to, drilling devices, riveters, mechanical and electromagnetic dent pullers, welders, wrenches, clamps, sanders, nailers, screw guns, or virtually any other desired type of manufacturing tools or measuring instruments. 
         [0052]      FIGS. 14 and 15  are flow charts of first and second portions, respectively, of a manufacturing process  600  that uses coordinate or “smart” pins in accordance with another embodiment of the disclosure. In this particular embodiment, the manufacturing process  600  is adapted for manufacture of wing spar of an aircraft wing assembly. It will be appreciated, however, that the manufacturing process  600  may alternately be adapted for the manufacture of any desired article of manufacture, and that embodiments of methods in accordance with the disclosure are not limited solely to the manufacture of a wing spar. 
         [0053]    As shown in  FIG. 14 , the manufacturing process  600  may begin with the formation of tool holes in one or more spar webs at a block  602 . The spar webs may then be at least one of formed, chemically treated, and primed at a block  604 . At a block  606 , one or more coordinate pins are applied (or installed) into the tool holes. As described more fully below, the coordinate pins (or smart pins) may remain installed in the tool holes throughout one or more subsequent actions of the manufacturing process  600 , and may advantageously be used by one or more pieces of manufacturing equipment throughout the manufacturing process  600 . The coordinate pins may, for example, be used to monitor spar growth, to locate spar features, to locate fasteners, to position sealant application machinery, to position automated wash and dry equipment, to obtain manufacturing plan information, or for any other suitable process or activity. At a block  608 , the spar chords are machined, and at a block  610 , the spar chords are at least one of formed, chemically treated, and primed. At a block  612 , measurements of the spar are performed for quality control, and one or more of the blocks  602  through  608  may be repeated as necessary. 
         [0054]    With continued reference to  FIG. 14 , at a block  614 , the spar webs and chords are sealed, attached together, and permanently coupled (e.g. tack fastened), and a chord locating device may be used to locate the chords and fasteners. A fastening system may install bolts on remaining chord and web locations at a block  616 . In a particular embodiment, an O-frame may be suitably employed to allow for quiet sealing of fasteners, and a lighter structure which may be suitable for bolts. An offline verification and maintenance of equipment may be performed at a block  618 . Again, measurements of the spar may be performed at a block  620 , and one or more previous steps may be repeated as needed. 
         [0055]    Next, at a block  622 , one or more coordinate holes may be drilled for ribposts, stiffeners, brackets, or other components. In one embodiment, a Low Cost Automation Technology (LCAT) adaptive feedback Determinant Assembly (DA) machine is used for these drilling operations. As used in this patent application, a DA machine is a machine that uses matching part-to-part features (e.g. holes, etc.) to assemble a product accurately versus using traditional locating jigs or special tools. At a block  624 , an offline verification and maintenance of equipment may be performed. The ribposts and stiffeners may be sealed as required, and installed (e.g. manually) using permanent fasteners in corresponding coordination holes at a block  626 . The ribposts and stiffeners may be provided with DA holes at a block  628 . Relevant information regarding the manufacturing operation  600  may be transmitted to a manufacturing plan information system at a block  630 . Similarly, at a block  632 , one or more miscellaneous brackets may be sealed as required, and installed (e.g. manually) using permanent fasteners in corresponding coordination holes, and at a block  634 , the brackets may be provided with DA holes. At a block  636 , a fastening system installs fasteners at appropriate ribpost, stiffener, and bracket locations. Information from the offline verification and maintenance of equipment at the block  624  may be received into the block  636  for this purpose. In a particular embodiment, for example, an LCAT O-frame fastening system installs bolts and/or rivets during the block  636 . The manufacturing process  600  continues at a block  638 . 
         [0056]    Referring now to  FIG. 15 , measurements of the wing spar may be performed at a block  640 , and one or more previous steps may be repeated as needed. At a block  642 , coordination holes may be formed for leading edge (LE) web stiffeners and second stage fittings. As described above, in one representative embodiment, an LCAT adaptive feedback DA machine is used for this purpose. Information may be transmitted to or received from an offline verification and maintenance of equipment at a block  644  (or from the block  624 ). Then, using the web stiffeners from the block  628 , the web stiffeners and second stage fittings are sealed as required, and permanent fasteners installed in the coordination holes, at a block  646 . At a block  648 , information from the manufacturing plan information system may be provided to the block  646 . 
         [0057]    As further shown in  FIG. 15 , fasteners may be installed into the LE stiffeners and second stage fittings at a block  650 . Again, information may be transmitted to or received from an offline verification and maintenance of equipment at a block  652  (or from the block  624 ). The second stage fittings pick-up operations are performed at a block  654 . Again, at a block  656 , information from the manufacturing plan information system may be provided to the block  654 . A spar cleaning is performed at a block  658 . In one particular embodiment, the cleaning may be a “car wash” type of cleaning. At a block  660 , the spar fillet is sealed (e.g. with an application system). Sealing pick-up operations are performed at a block  662 . Information may be provided at the block  662  from the manufacturing plan information system (block  656 ). Finally, at a block  664 , at least one of a leading edge attachment and a shipping of the part for final assembly is performed. 
         [0058]      FIG. 16  is an isometric view of a manufacturing operation  700  in accordance with yet another embodiment of the disclosure. In this embodiment, a workpiece  702  (e.g. a wing spar) is being carried by handling equipment  704  while an operator  706  manually applies a plurality of coordinate pins (or smart pins or smart buttons)  710  into a corresponding plurality of holes  708  in the workpiece  702 . The holes  708  may be formed by any desired method, including, for example, Determinant Spar Assembly Cell (DSAC), Automated Spar Assembly Tool (ASAT), robot, milling machine, or any other suitable drilling device or method. The coordinate pins  710  may be installed in specific tool hole locations. In one embodiment, the coordinate pins  710  are so-called “quick disconnect” pins. In a particular embodiment, the coordinate pins  710  can include industry-standard HSK type machine tool holders to improve dimensional accuracy. Other suitable types of coordinate pin systems could also be used. 
         [0059]    It may be noted that each of the coordinate pins  710  installed in the workpiece  702  may be individualized and may contain highly specific characteristics or identification information that is unique to the specified location of each respective coordinate pin  710 . Therefore, placement of the coordinate pins  710  into the workpiece  702  may be checked and certified, for example, by a second operator or quality assurance inspector (not shown). The coordinate pins  710  may be kept in a precision equipment box and color-coded, or otherwise marked, for placement in a specific hole location  708 . Also, upon completion of manufacturing operations on the workpiece  702 , the coordinate pins  710  may be removeable and reusable for similar manufacturing operations on subsequent workpieces  702 . For example, a process for installing the coordinate pins  710  could start by assigning a box containing a set of unique coordinate pins  710  to a specific workpiece  702  (e.g. a front wing spar Part No. IGW-200 for a Model 777 aircraft commercially-available from The Boeing Company of Chicago, Ill.). The coordinate pins  710  may be designated for their respective index hole  708  in the workpiece  702  by, for example, color coding of the pins, or cross-referencing numbers that are affixed or stamped on the pins, or any other suitable means. The operator  706  select the correct box of coordinate pins  710  to install for the respective workpiece  702 , and then install each coordinate pin  710  into its corresponding index hole  708 . 
         [0060]      FIG. 17  shows enlarged, partial cross-sectional and end elevational views of a coordinate pin  710  of  FIG. 16 , and a coordinate pin reader  730 , in accordance with another embodiment of the disclosure. As shown in  FIG. 17 , the coordinate pin  710  may include an identifier  712  containing identification information that may be useful in the performance of one or more actions of the manufacturing process  600  ( FIGS. 14 and 15 ). In one embodiment, for example, the identifier  712  may be embedded within a tip portion of the coordinate pin  710 . In an engaged position  740 , the pin reader  730  may be engaged with the coordinate pin  710  so that a receiving member  732  of the pin reader  730  engages with the identifier  712  and receives the identification information contained therein. The identification information may be transmitted via a conductive lead  734  to a data acquisition system (not shown), a controller, a manufacturing plan information system, or other suitable data analysis and storage system. 
         [0061]    In one particular embodiment, the identifier  712  may be a sensor that is embedded into the coordinate pin  710 . A number of different types of contact and non-contact sensors are commercially-available that may be used for this purpose. For example, in one exemplary embodiment, a sensor known as a “smart button” available from Dallas Semiconductor, Inc. of Dallas, Tex. may be employed that is about the size of a typical watch battery and has a unique character string identifier that is embedded in a microchip. Each smart button is robust and costs only a few dollars. A smart button reader  730  can read the smart button&#39;s unique identifier by simply touching the surface of the smart button. An electrical micro voltage potential between the reader  730  and the button  710  provides the power source to read the button  710 . Once the smart buttons  710  are installed then multiple pieces of manufacturing equipment can hook up to any of the coordinate pin locations and read the unique character string identifier for that location. The manufacturing system can then automatically look up the unique character identifier in a table, and may cross-reference the workpiece information for that location. 
         [0062]    For example, in one representative embodiment, a piece of automated drilling equipment, such as the manufacturing assembly  400  described above and shown in  FIG. 13 , may be attached to the coordinate pin  710 . The drilling equipment may include a pin reader  730  (e.g. in its secondary controller  430  or its manufacturing tool  451 ), and may download the identification information of the coordinate pin  710  to, for example, the primary controller  434 . The primary controller  434  may perform the table look up on the identification information. The identification information may be cross-referenced to the workpiece of interest, and other various details about the manufacturing operation (e.g. airplane model, structure, station number, and data sets for that location). The primary controller  434  may then formulate one or more control signals to the carriage assembly  420  or the manufacturing tool  451  accordingly. 
         [0063]    The identification information in the coordinate pin  710  may advantageously allow unique identification of each index hole  708  location so that manufacturing equipment will be better able to know where and what assembly operations are to be performed on the workpiece  702 . For example, in the representative manufacturing process  600  shown in  FIGS. 14 and 15 , the coordinate pins  710  may be installed, for example, in the block  606 . Subsequently, the coordinate pins  710  may be employed during various operations and sub-processes of the manufacturing process  600 , including, for example, for monitoring spar growth, for locating spar features, to position sealant application machinery, to position washing and drying equipment, to obtain manufacturing plan information, and during any other suitable operation or sub-process. More specifically, in the manufacturing process  600  shown in  FIGS. 14 and 15 , the coordinate pins  710  may be used in numerous processes and sub-processes, including, for example, in blocks  614  through  624 , in block  630 , in blocks  636  and  642 , in block  650 , and in blocks  656  through  660 . 
         [0064]    Furthermore, the coordinate pins  710  may remain in the workpiece  702  as the workpiece  702  progresses beyond the manufacturing process  600 . In a particular embodiment, for example, the coordinate pins  710  remain in the wing spar  702  after a spar assembly process and into a wing majors assembly process. The wing majors assembly process may use the coordinate pins for the same or similar purposes and uses as during the manufacturing process  600 . When manufacturing operations are complete, the coordinate pins  710  may be finally removed and recycled for the next workpiece  702 . Thus, the coordinate pins  710  may advantageously establish a common index throughout a production process. 
         [0065]    Embodiments of apparatus and methods that include indexing in accordance with the teachings of the present disclosure may allow a dramatic reduction or elimination of at least some of the traditional tools and traditional “monument like” equipment involved in conventional manufacturing processes. Embodiments of methods and apparatus disclosed herein may be relatively lower cost, relatively simple, and relatively flexible and adaptable in comparison with prior art manufacturing apparatus and methods. Traditional hard tooling and indexing systems are relatively more expensive to design, build, and maintain in comparison with the inventive indexing apparatus and methods disclosed herein. Since tooling for large manufacturing operations, such as a new airplane, typically comprises a substantial percentage of the capital investment needed to begin manufacturing operations, the cost savings attributable to apparatus and methods in accordance with the present disclosure may be substantial. 
         [0066]    It will also be appreciated that apparatus and methods in accordance with the present disclosure may also provide other advantages over prior art manufacturing apparatus and methods. For example, embodiments of the present disclosure may allow index locations to be identified relatively quickly, and may provide a convenient method for configuration control in automated processing operations. Also, embodiments of the present disclosure may provide a method for communicating key manufacturing instructions throughout the manufacturing process at relatively low cost and high reliability. Embodiments of the present disclosure may also provide a method of “mistake proofing” manufacturing operations to reduce or eliminate manufacturing errors. 
         [0067]    While specific embodiments of the disclosure have been illustrated and described herein, as noted above, many changes can be made without departing from the spirit and scope of the disclosure. Accordingly, the scope of the disclosure should not be limited by the disclosure of the specific embodiments set forth above. Instead, the disclosure should be determined entirely by reference to the claims that follow.