Patent Publication Number: US-2021188461-A1

Title: Method and apparatus for forming a composite fuselage structure

Description:
FIELD 
     This disclosure generally relates to composite manufacturing and, more particularly, to methods and apparatuses for fabricating a composite fuselage structure by integrating a fuselage skin and fuselage stringers comprised of overbraided material. 
     BACKGROUND 
     Different types of aircraft structures may be fabricated using composite materials. Currently, many aircraft structures are formed using thermoset composite materials. However, using thermoset composite materials (e.g., thermoset resin) may be more challenging than desired when fabricating larger sized and shaped aircraft structures, such as fuselage barrel sections. Further, the process involved in using thermoset composite materials for such structures may be more time-consuming and costly than desired. 
     For example, the process of fabricating a fuselage barrel section using a thermoset composite material may involve more facility resources (e.g., facility equipment) and tooling than desired. Additionally, traditional methods involving the use of an autoclave to cure a fuselage barrel structure comprised of thermoset composite material may be slower than desired with respect to production rate requirements. Meeting such production rate requirements may require a more significant investment in capital, equipment, facility resources, or a combination thereof than desired. 
     Therefore, it would be desirable to have a method and apparatus that takes into account at least some of the issues discussed above, as well as other possible issues. 
     SUMMARY 
     In one illustrative example, a method is provided for forming a composite structure. An inner tooling, a stackup, and an outer tooling are held in place together using a load constraint. A bladder and a plurality of stringer bladders in the stackup are pressurized to cause expansion of the bladder and the plurality of stringer bladders, thereby pushing together an overbraided thermoplastic skin and a plurality of overbraided thermoplastic members in the stackup. The overbraided thermoplastic skin and the plurality of overbraided thermoplastic members are co-consolidated while the bladder and the plurality of stringer bladders are pressurized to form the composite structure. 
     In another illustrative example, an apparatus comprises a bladder, a plurality of cauls, a plurality of overbraided thermoplastic members, a plurality of stringer bladders, and an overbraided thermoplastic skin. The bladder has a plurality of recessed portions. The plurality of cauls is positioned within the plurality of recessed portions. The plurality of overbraided thermoplastic members is positioned over the plurality of cauls. The plurality of stringer bladders is positioned over the plurality of overbraided thermoplastic members. The overbraided thermoplastic skin is positioned over the plurality of stringer bladders and the plurality of overbraided thermoplastic members. 
     In yet another illustrative example, a system comprises an inner tooling, an outer tooling, a first smart susceptor, and a second smart susceptor. The inner tooling comprises a dielectric material and is embedded with first induction coils. The outer tooling comprises the dielectric material and is embedded with second induction coils and shaped and sized to surround the inner tooling. The first smart susceptor lines the inner tooling. The second smart susceptor lines the outer tooling. When the first induction coils and the second induction coils are used to inductively heat a stackup positioned between the inner tooling and the outer tooling, both the first smart susceptor and the second smart susceptor help distribute heat and ensure thermal uniformity. 
     The features and functions can be achieved independently in various embodiments of the present disclosure or may be combined in yet other embodiments in which further details can be seen with reference to the following description and drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The novel features believed characteristic of the example embodiments are set forth in the appended claims. The example embodiments, however, as well as a preferred mode of use, further objectives and features thereof, will best be understood by reference to the following detailed description of an example embodiment of the present disclosure when read in conjunction with the accompanying drawings. 
         FIG. 1  is a block diagram of a manufacturing environment in accordance with an example embodiment. 
         FIG. 2  is a more detailed illustration of a stackup in accordance with an example embodiment. 
         FIG. 3A  is an illustration of an isometric view of a consolidation setup in accordance with an example embodiment. 
         FIG. 3B  is an illustration of a cross-sectional view of the consolidation setup from  FIG. 3A  in accordance with an example embodiment. 
         FIG. 4  is an illustration of a portion of the inner tooling from  FIG. 3  taken between lines  4 - 4  in  FIG. 3  in accordance with an example embodiment. 
         FIG. 5  is an illustration of cauls added to the stackup from  FIG. 4  in accordance with an example embodiment. 
         FIG. 6  is an illustration of overbraided thermoplastic members added to the stackup from  FIG. 5  in accordance with an example embodiment. 
         FIG. 7  is an illustration of stringer bladders added to the stackup from  FIG. 6  in accordance with an example embodiment. 
         FIG. 8  is an illustration of an overbraided thermoplastic skin added to the stackup from  FIG. 7  in accordance with an example embodiment. 
         FIG. 9  is an illustration of the second smart susceptor and outer tooling positioned around the stackup from  FIG. 8  in accordance with an example embodiment. 
         FIG. 10  is an illustration of a cross-sectional view of a system for supporting the consolidation setup during consolidation in accordance with an example embodiment. 
         FIG. 11A  is an illustration of a portion of the consolidation setup from  FIG. 10  in which the plugs are more clearly seen in accordance with an example embodiment. 
         FIG. 11B  is an illustration of an enlarged view of one configuration for the pressurization tube from  FIG. 11A  in accordance with an example embodiment. 
         FIG. 11C  is an illustration of an enlarged view of another configuration for the pressurization tube from  FIG. 11A  in accordance with an example embodiment. 
         FIG. 11D  is an illustration of an enlarged view of yet another configuration for the pressurization tube from  FIG. 11A  in accordance with an example embodiment. 
         FIG. 12  is an illustration of a cross-sectional view of the stackup taken with respect to lines  12 - 12  in  FIG. 11  in accordance with an example embodiment. 
         FIG. 13A  is an illustration of an isometric view of a tacking-trimming setup in accordance with an example embodiment. 
         FIG. 13B  is an illustration of cross-sectional view of the tacking-trimming setup from  FIG. 13A  in accordance with an example embodiment. 
         FIG. 14  is an illustration of a cross-sectional view of a portion of the tacking-trimming setup in  FIG. 13  in accordance with an example embodiment. 
         FIG. 15  is a flowchart of a process for forming a composite structure in accordance with an example embodiment. 
         FIG. 16  is a flowchart of a process for building a stackup in accordance with an example embodiment. 
         FIG. 17  is a flowchart of a process for building a system that includes a consolidation setup in accordance with an example embodiment. 
         FIG. 18  is a flowchart of a process for building a system to form a composite fuselage structure in accordance with an example embodiment. 
         FIG. 19  is a flowchart of a process for inductively consolidating an overbraided thermoplastic skin with overbraided thermoplastic members to form a composite fuselage structure in accordance with an example embodiment. 
         FIG. 20  is a flowchart of a process for forming a composite structure in accordance with an example embodiment. 
         FIG. 21  is a flowchart of a process for forming a composite fuselage structure in accordance with an example embodiment. 
         FIG. 22  is a flowchart of a process for forming a composite structure in accordance with an example embodiment. 
         FIG. 23  is a flowchart of a process for forming a composite structure in accordance with an example embodiment. 
         FIG. 24  is a flowchart of a process for forming a composite structure in accordance with an example embodiment. 
         FIG. 25  is a flowchart of a process for tacking and trimming a thermoplastic tow in accordance with an example embodiment. 
         FIG. 26  is a flowchart of a process for tacking and trimming a thermoplastic tow in accordance with an example embodiment. 
         FIG. 27  is an illustration of an aircraft manufacturing and service method in accordance with an example embodiment. 
         FIG. 28  is a block diagram of an aircraft in accordance with an example embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     The example embodiments described below provide methods, apparatuses, and systems for rapidly and efficiently fabricating composite structures such as fuselage barrel sections at reduced cost and weight. In particular, using thermoplastic materials to fabricate a composite structure such as a fuselage barrel section may help reduce overall fabrication costs and production times. 
     The example embodiments described methods, apparatuses, and systems that eliminate the need for autoclaves to cure fuselage barrel structures. The use of autoclaves may be more expensive than desired. Further, autoclaves have thermal mass requirements due to their size and complexity that make using autoclaves more time-consuming and less efficient than desired for fabricating fuselage barrel sections. By eliminating the need for autoclaves, the example embodiments described herein reduce the cost and time needed to fabricate fuselage barrel sections. For example, at least some of the example methods for fabricating a fuselage barrel structure described herein may take one tenth of the time that would be required when using an autoclave. 
     Further, using the systems described herein, less overall heating is required because thermoplastic materials are fully reacted and therefore no curing is required. The systems described herein require less overall equipment and less complex equipment for the fabrication of fuselage barrel sections as compared to those systems involving autoclaves. 
     The example embodiments describe creating a composite structure, such as a fuselage barrel section, using overbraided thermoplastic stringers consolidated to an overbraided thermoplastic skin. Induction heating is used to perform this consolidation in a relatively inexpensive, rapid, and reliable manner. As used herein, “consolidation” or a “consolidation process” refers to the process by which components comprised of overbraided thermoplastic material are heated to melting such that the components can be joined, fused, or integrated with each other. This heating is performed using smart susceptors that allow for fast heating to a selected temperature and then maintaining that temperature precisely. The process may further include cooling the components after this joining or integration process to result in a fully integrated structure. 
     Once the integrated fuselage barrel structure has been fabricated, other fuselage components may be easily welded to or otherwise attached to the fuselage barrel structure. For example, without limitation, skin tear straps, pad-ups, and local reinforcements for a door cutout and service door area may be induction-welded to the fuselage barrel structure via high rate production fiber placement and stacking placement of thermoplastic materials. Fuselage and window frames and other components (e.g., tear straps, intercostals, doublers, shear ties, systems brackets, etc.) may also be welded into place using induction welding technology. 
     Thus, the example embodiments described below provide methods, apparatuses, and systems for forming a composite structure using thermoplastic materials and induction heating. In one example embodiment, a stackup is built in which the stackup a plurality of overbraided thermoplastic members and an overbraided thermoplastic skin. The stackup may also include a bladder having a plurality of recessed portions, a plurality cauls within the plurality of recessed portions, and a plurality of stringer bladders. The stackup is placed between an inner tooling and an outer tooling. A load constraint is used to hold the inner tooling, the stackup, the outer tooling in place. The consolidation setup is heated to form the composite structure. This heating, which may be performed via induction and using smart susceptors, co-consolidates the plurality of overbraided thermoplastic members with the overbraided thermoplastic skin to thereby form the composite structure. 
     Referring now to the figures,  FIG. 1  is a block diagram of a manufacturing environment  100  in accordance with an example embodiment. Within manufacturing environment  100 , composite structure  101  is formed. In these illustrative examples, composite structure  101  takes the form of composite fuselage structure  102 . Composite fuselage structure  102  may be, for example, a composite barrel section. In other illustrative examples, composite structure  101  may take some other form. 
     Composite structure  101  is formed using system  103 . System  103  includes consolidation setup  104 , end tooling  105 , a plurality of plugs  106 , and a plurality of connector devices  107 . In these illustrative examples, consolidation setup  104  includes inner tooling  108 , outer tooling  110 , stackup  112 , first smart susceptor  114 , second smart susceptor  115 , support structure  116 , and load constraint  117 . 
     Inner tooling  108  includes a plurality of induction coils  118  embedded within inner tooling  108 . In some examples, inner tooling  108  is also embedded with a plurality of rods  119 . Rods  119  may take the form of, for example, without limitation, fiberglass rods. Rods  119  are used to reinforce inner tooling  108  and to load inner tooling  108  during compression. 
     Similar to inner tooling  108 , outer tooling  110  includes a plurality of induction coils  120  embedded within outer tooling  110 . Inner tooling  108  and outer tooling  110  may be comprised of a same material or different types of materials. In one illustrative example, inner tooling  108  and outer tooling  110  are both comprised of a ceramic material. 
     Stackup  112  is positioned between inner tooling  108  and outer tooling  110 . In particular, stackup  112  is positioned between first smart susceptor  114  and second smart susceptor  115 , which are located between inner tooling  108  and outer tooling  110 . For example, first smart susceptor  114  is positioned between stackup  112  and inner tooling  108 . Second smart susceptor  115  is positioned between stackup  112  and outer tooling  110 . 
     In these illustrative examples, first smart susceptor  114  and second smart susceptor  115  are considered separate from inner tooling  108  and outer tooling  110 , respectively. But in other illustrative examples, first smart susceptor  114  may be integrated with or otherwise considered part of inner tooling  108 , and second smart susceptor  115  may be integrated with or otherwise considered part of outer tooling  110 . For example, first smart susceptor  114  and second smart susceptor  115  may be considered liners for inner tooling  108  and outer tooling  110 , respectively. 
     Both first smart susceptor  114  and second smart susceptor  115  are electrically conductive and have high thermal conductivity. Both of these smart susceptors absorb electromagnetic energy and convert such electromagnetic energy into heat. For example, induction coils  118  and induction coils  120  may generate an electromagnetic flux field. First smart susceptor  114  and second smart susceptor  115  may be positioned within the electromagnetic flux field and includes a magnetically permeable material that responds to the electromagnetic flux field to generate heat. 
     A “smart susceptor,” such as first smart susceptor  114  or second smart susceptor  115 , is typically comprised of a material or materials that generates heat efficiently until reaching a threshold temperature (i.e., a Curie temperature). As portions of the smart susceptor reach the threshold temperature, the magnetic permeability of those portions decreases. This decrease in magnetic permeability limits the generation of heat by those portions of the smart susceptor and shifts the magnetic flux to the lower-temperature portions causing these lower-temperature portions to more quickly heat up to the threshold temperature. 
     In this manner, first smart susceptor  114  and second smart susceptor  115  are used to help distribute heat and ensure thermal uniformity when stackup  112  is inductively heated via induction coils  118  and induction coils  120 . This inductive heating is used to thermally consolidate overbraided thermoplastic components, described below in  FIG. 2 , within stackup  112 . 
     Support structure  116  provides support for consolidation setup  104  and is used to hold inner tooling  108  in place. In some examples, support structure  116  is referred to as a mandrel or inner mandrel. Inner tooling  108  is positioned around support structure  116 . 
     Load constraint  117  is positioned around outer tooling  110  and helps hold the various components of consolidation setup  104  in place. In particular, load constraint  117  helps hold inner tooling  108 , first smart susceptor  114 , stackup  112 , second smart susceptor  115 , and outer tooling  110  in place relative to each other during the formation of composite structure  101 . 
     Consolidation setup  104  has first end  122  and second end  124 . Stackup  112  within consolidation setup  104  has first end  126  and second end  128 . In these illustrative examples, plugs  106  are located at first end  126  and second end  128  of stackup  112 . End tooling  105  is located at first end  122  and second end  124  of consolidation setup  104  and used to support and secure plugs  106 . 
     Connector devices  107  are used to connect induction coils  118  with induction coils  120 . Connector devices  107  may be located at both first end  122  and second end  124  of consolidation setup  104 . Connector devices  107  may take different forms. In one illustrative example, each of connector devices  107  takes the form of knife switch connector  127 . Knife switch connector  127  may be, for example, a bar of copper or some other highly conductive material that is capable of rotating about a fixed pivot point  129 . 
     Consolidation setup  104  is heated inductively using induction coils  118  and induction coils  120 . In particular, first smart susceptor  114  and second smart susceptor  115  are heated inductively via induction coils  118  and induction coils  120 . These smart susceptors help ensure thermal uniformity in stackup  112 , within selected tolerances, during consolidation. In the illustrative examples in which composite fuselage structure  102  is being formed, the result of this consolidation is the integration of a plurality of fuselage stringers  130  with fuselage skin  132 . 
     Fuselage skin  132  may be a circumferential skin in these illustrative examples. For example, fuselage skin  132  may be used to form a full fuselage barrel section. In other illustrative examples, fuselage skin  132  may be curved and formed into a half fuselage barrel section, a quarter fuselage barrel section, or some other type of partial fuselage barrel section. 
       FIG. 2  is a more detailed illustration of stackup  112  from  FIG. 1  in accordance with an example embodiment. Stackup  112  includes bladder  202 , a plurality of cauls  204 , a plurality of overbraided thermoplastic members  206 , a plurality of stringer bladders  208 , and overbraided thermoplastic skin  210 . These components of stackup  112  are positioned relative to each other in a particular manner when used in system  103  to form composite structure  101 . 
     In these illustrative examples, bladder  202  is shaped such that bladder  202  has a plurality of recessed portions  212  and a plurality of caps  214 . Each of recessed portions  212  is located between two of caps  214 . Recessed portion  216  is an example of one of recessed portions  212 . Recessed portion  216  is located between cap  218  and cap  220  of caps  214 . Recessed portion  216  includes main section  222 , stepped section  224 , and stepped section  226 . Stepped section  224  is located at a first edge of recessed portion  216  near cap  218 . Stepped section  226  is located at a second edge of recessed portion  216  near cap  220 . Main section  222  extends between stepped section  224  and stepped section  226 . In some examples, main section  222  includes a base section (that may form the “cap” portion of a hat stringer) and two webbed sections that extend from this base section to stepped section  224  and stepped section  226 . 
     Bladder  202  may be comprised of a material that provides a desired level of elasticity and compliance at high temperatures. In these illustrative examples, bladder  202  may be comprised of aluminum (which may be an aluminum alloy). The aluminum provides a desired level of elasticity and compliance at higher temperatures (e.g., temperatures over about 500 degrees Fahrenheit). In one illustrative example, bladder  202  is comprised of an aluminum alloy such as 5083 aluminum alloy, which is an aluminum alloyed with magnesium and traces of manganese and chromium. In other examples, bladder  202  may be referred to as an inner mold line (IML) bladder. 
     Cauls  204  are positioned within recessed portions  212  of bladder  202 . For example, each of cauls  204  may be positioned within a corresponding one of recessed portions  212 . Cauls  204  are used to provide a stable, rigid, and smooth surface for overbraided thermoplastic members  206 . Each of cauls  204  is comprised of a material selected to provide a desired level of strength to cauls  204  without requiring cauls  204  be thicker than desired. Further, each of cauls  204  is comprised of a material selected such that cauls  204  have first coefficient of thermal expansion  227 . 
     Caul  228  is an example of one of cauls  204 . Caul  228  may be positioned within recessed portion  216  when used in stackup  112 . Caul  228  may be between about ⅙ th  of an inch to about 1/10 th  of an inch in thickness. In one illustrative example, caul  228  is about ⅛ th  of an inch in thickness. Caul  228  may be comprised of a nickel-iron alloy in these illustrative examples. In one illustrative example, caul  228  is comprised of an invar alloy comprising between about 40 percent to about 43 percent nickel (e.g., Invar 42). In some illustrative examples, caul  228  may be referred to as an invar caul. 
     Caul  228  may be shaped to substantially conform to or match recessed portion  216  of bladder  202 . For example, caul  228  may have main section  230 , flanged section  232 , and flanged section  234 . Main section  230  substantially matches main section  222  of recessed portion  216 . Thus, in some cases, main section  230  includes a base section and two webbed sections extending from the base section to flanged section  232  and flanged section  234 . Flanged section  232  is shaped to fit within or sit over stepped section  224 . Similarly, flanged section  234  is shaped to fit within or sit over stepped section  226 . 
     Overbraided thermoplastic members  206  are positioned over cauls  204 . In particular, each of overbraided thermoplastic members  206  is positioned relative to a corresponding one of cauls  204 . Overbraided thermoplastic members  206  are shaped similarly to cauls  204 . In these illustrative examples, cauls  204  and overbraided thermoplastic members  206  have thicknesses that ensure overbraided thermoplastic members  206  do not extend past the profile (e.g., circumferential profile) of bladder  202  defined by caps  214  of bladder  202 . 
     Overbraided thermoplastic members  206  may be formed using available apparatuses and techniques for overbraiding continuous fibers of thermoplastic composite materials. Overbraiding enables a large number of spools of continuous fiber thermoplastic materials to be used at once. For example, with overbraiding, the spools may number in the hundreds, thereby enabling high rates of material application. 
     Overbraided thermoplastic members  206  have second coefficient of thermal expansion  235 . In these illustrative examples, first coefficient of thermal expansion  227  of cauls  204  is within a desired range of second coefficient of thermal expansion  235  of overbraided thermoplastic members  206 . 
     For example, cauls  204  may be made from a material such that first coefficient of thermal expansion  227  of cauls  204  is closer to second coefficient of thermal expansion  235  of overbraided thermoplastic members  206  as compared to third coefficient of thermal expansion  237  of bladder  202 . In some cases, the material of cauls  204  may be selected such that first coefficient of thermal expansion  227  of cauls  204  is as close as possible to second coefficient of thermal expansion  235  of overbraided thermoplastic members  206 . 
     With cauls  204  and overbraided thermoplastic members  206  having coefficients of thermal expansion that are close, cauls  204  are capable of maintaining a desired strength and rigidity during induction heating to help overbraided thermoplastic members  206  retain their smoothness and shape during induction heating. For example, the aluminum that makes up bladder  202  may have third coefficient of thermal expansion  237  that is not close to second coefficient of thermal expansion  235  of overbraided thermoplastic members  206 . For example, third coefficient of thermal expansion  237  may be much lower than second coefficient of thermal expansion  235 . Therefore, during induction heating, bladder  202  may soften. Without cauls  204 , the softening of bladder  202  might cause undesired undulations in overbraided thermoplastic members  206 . Thus, cauls  204  provide a well-defined surface for overbraided thermoplastic members  206  while reducing or eliminating the potential issues associated with the differences in coefficients of thermal expansion between bladder  202  and overbraided thermoplastic members  206 . 
     Stringer bladders  208  are positioned over overbraided thermoplastic members  206 . Stringer bladders  208  are shaped to nest within the remaining space within recessed portions  212  of bladder  202  without extending beyond the profile (e.g., circumferential profile) of bladder  202 . 
     In these illustrative examples, stringer bladders  208  may be comprised of an aluminum (which may be an aluminum alloy). The aluminum may provide a desired level of elasticity and compliance at higher temperatures (e.g., temperatures over about 500 degrees Fahrenheit). For example, during induction heating, the aluminum may become compliant and soft such that stringer bladders  208  provide substantially even pressure over overbraided thermoplastic members  206 . In other words, stringer bladders  208  comprised of aluminum help provide even pneumatic pressure to help ensure that a pressure gradient is not created. In one illustrative example, stringer bladders  208  are comprised of an aluminum alloy such as 5083 aluminum alloy, which is an aluminum alloyed with magnesium and traces of manganese and chromium. 
     Overbraided thermoplastic skin  210  is positioned over stringer bladders  208  in a manner such that overbraided thermoplastic skin  210  also contacts portions  236  of overbraided thermoplastic members  206  and caps  214  of bladder  202 . During induction heating, overbraided thermoplastic skin  210  is consolidated with overbraided thermoplastic members  206 . 
     In particular, overbraided thermoplastic skin  210  and overbraided thermoplastic members  206  are co-consolidated. Induction heating is used to heat overbraided thermoplastic skin  210  and overbraided thermoplastic members  206  to melting such that overbraided thermoplastic skin  210  and overbraided thermoplastic members  206  are integrated or joined together. In this manner, after consolidation and cooling, overbraided thermoplastic skin  210  and overbraided thermoplastic members  206  together form a single, integrated structure, composite structure  101  in  FIG. 1 . In some cases, one or more additional consolidation processes may be performed to integrate or join other structural features to composite structure  101 . 
     More specifically, overbraided thermoplastic skin  210  is consolidated with portions  236  of overbraided thermoplastic members  206  to form an integrated composite structure  101 . When composite structure  101  takes the form of composite fuselage structure  102 , overbraided thermoplastic skin  210  form fuselage skin  132  and overbraided thermoplastic members  206  form fuselage stringers  130 . 
     In these illustrative examples, a plurality of pressurization tubes  238  may be inserted within or passed through stringer bladders  208 . Pressurization tubes  238  may at least partially extend into stringer bladders  208 . Pressurization tubes  238  help apply pressure within stringer bladders  208 . For example, a pressurization system (not shown) may connect to pressurization tubes  238  through tubing to allow an inert gas to flow through pressurization tubes  238 . 
     In some examples, each of pressurization tubes extends into but does not fully extend through a corresponding one of stringer bladders  208 . For example, pressurization tubes  238  may open into corresponding ones of stringer bladders  208 . This allows the inert gas flowing through pressurization tubes  238  to exit out of pressurization tubes  238  into stringer bladders  208  to thereby pressurize stringer bladders  208 . In other examples, each of pressurization tubes  238  may extend through the entire length of the corresponding one of stringer bladders  208 . But in these cases, pressurization tubes  238  have openings (e.g., perforations, slits, holes or some other type of openings) that allow the inert gas to enter stringer bladders  208 . The pressurization system controls the flow of the inert gas and uses the inert gas to control the pressure within stringer bladders  208 . 
     In one illustrative example, pressurization tubes  238  are comprised of aluminum. In other examples, pressurization tubes  238  may be comprised of stainless steel, some other type of material, or a combination thereof. The pressurization system may use the inert gas to increase the pressure within pressurization tubes  238 , and thereby stringer bladders  208 . During induction heating, this pressurization helps stringer bladders  208  expand to provide support to overbraided thermoplastic members  206  to prevent overbraided thermoplastic from caving in (or collapsing inward) or otherwise moving out of a desired shape. Additionally, this pressurization helps stringer bladders  208  expand to provide a smooth surface for overbraided thermoplastic members  206  and overbraided thermoplastic skin  210 . 
     Further, the pressure within bladder  202  may also be controlled using pressurization tube  240  that extends into bladder  202  and the pressurization system described above. For example, pressurization tube  240  may also be comprised of aluminum. In other examples, pressurization tube  240  may be comprise of stainless steel, some other material, or a combination thereof. The pressurization system may use the inert gas to control the pressure within pressurization tube  240 , and thereby bladder  202 , similar to pressurization tubes  238 . 
     In one illustrative example, pressurization tube  240  enters into bladder  202  without extending all the way through bladder  202 . In this manner, inert gas may flow out of pressurization tube  240  and into bladder  202  to thereby pressurize bladder  202 . In other examples, pressurization tube  240  has openings (e.g., perforations, slits, holes, or some other type of opening) that allows gas to flow from pressurization tube  240  into bladder  202 . 
     Each of stringer bladders  208  is pressurized to a substantially same pressure (i.e., a same pressure within selected tolerances) during consolidation. This helps ensure that the expansion of each of stringer bladders  208  is even such that the same force is applied to each of overbraided thermoplastic members  206  during consolidation. In some cases, bladder  202  and stringer bladders  208  are pressurized to a substantially same pressure during consolidation of overbraided thermoplastic members  206  to overbraided thermoplastic skin  210 . Increasing the pressure within bladder  202  and stringer bladders  208  causes some expansion, which places the preform (i.e., overbraided thermoplastic members  206  and overbraided thermoplastic skin  210 ) in tension during processing. Further, this expansion helps co-consolidate stackup  112  during processing by pushing against or compressing stackup  112  against outer tooling  110 . 
     System  103  of  FIG. 1  with stackup  112  of  FIGS. 1 and 2  allows consolidation of overbraided thermoplastic members  206  with overbraided thermoplastic skin  210  to form composite structure  101  in an efficient manner at rapid rates. In particular, using induction heating via induction coils  118 , induction coils  120 , first smart susceptor  114 , and second smart susceptor  115  helps ensure a rapid and reliable consolidation process. 
     The illustrations of manufacturing environment  100  and system  103  in  FIG. 1  and stackup  112  in  FIGS. 1 and 2  are not meant to imply physical or architectural limitations to the manner in which an illustrative embodiment may be implemented. Other components in addition to or in place of the ones illustrated may be used. Some components may be optional. Also, the blocks are presented to illustrate some functional components. One or more of these blocks may be combined, divided, or combined and divided into different blocks when implemented in an illustrative embodiment. 
       FIGS. 3A and 3B  are illustrations of a consolidation setup in accordance with an example embodiment.  FIG. 3A  is an illustration of an isometric cross-sectional view of the consolidation setup. Consolidation setup  300  is an example of one implementation for consolidation setup  104  in  FIG. 1 . 
     Consolidation setup  300  includes support structure  302 , inner tooling  304 , stackup  306 , outer tooling  308 , and load constraint  310 . Consolidation setup  300  further includes first smart susceptor  311  and second smart susceptor  312 . First smart susceptor  311  is positioned between inner tooling  304  and stackup  306  and second smart susceptor  312  is positioned between stackup  306  and outer tooling  308 . 
     Support structure  302 , inner tooling  304 , stackup  306 , outer tooling  308 , and load constraint  310  are examples of implementations for support structure  116 , inner tooling  108 , stackup  112 , outer tooling  110 , and load constraint  117 , respectively, in  FIG. 1 . First smart susceptor  311  and second smart susceptor  312  are examples of implementations for first smart susceptor  114  and second smart susceptor  115 , respectively, in  FIG. 1 . Support structure  302 , inner tooling  304 , stackup  306 , outer tooling  308 , load constraint  310 , first smart susceptor  311 , and second smart susceptor  312  are aligned with respect to longitudinal axis  301  (e.g., center longitudinal axis). In one illustrative example, these components are concentrically aligned with respect to longitudinal axis  301 . 
       FIG. 3B  is an illustration of a cross-sectional view of the consolidation setup from  FIG. 3A . The cross-sectional view of consolidation setup  300  in  FIG. 3B  is taken along a plane perpendicular to longitudinal axis  301  through consolidation setup  104 . In particular, the cross-sectional view of consolidation setup  300  in  FIG. 3B  is taken with respect to lines  3 B- 3 B in  FIG. 3A . 
     In these illustrative examples, support structure  302  provides support to inner tooling  304  and is separate from inner tooling  304 . In other illustrative examples, support structure  302  may be considered part of inner tooling  304  or integrated with inner tooling  304 . Inner tooling  304  has induction coils  313  embedded within inner tooling  304 . Induction coils  313  are an example of one implementation for induction coils  118  in  FIG. 1 . Outer tooling  308  has induction coils  314  embedded within outer tooling  308 . Induction coils  314  are an example of one implementation for induction coils  118  in  FIG. 1 . 
     In one or more illustrative examples, inner tooling  304 , stackup  306 , outer tooling  308 , and load constraint  310  are substantially cylindrical structures. For example, inner tooling  304 , stackup  306 , outer tooling  308 , and load constraint  310  may be concentrically aligned with respect to longitudinal axis  301 . In one illustrative example, inner tooling  304  is formed from a single cylindrical structure. In other illustrative examples, inner tooling  304  is formed from two halves that may be put together to form a cylindrical structure. 
     Both inner tooling  304  and outer tooling  308  may be comprised of a ceramic material. Ceramic material is a dielectric material that is “transparent” to and does not react with the magnetic energy produced by induction coils  313  and induction coils  314 . In this manner, the magnetic energy can pass through the ceramic material to interact with first smart susceptor  311  and second smart susceptor  312 . First smart susceptor  311  and second smart susceptor  312  convert the magnetic energy to thermal energy, but the ceramic material is considered “opaque” to the thermal energy so that the thermal energy does not pass through the ceramic material. In this manner, the ceramic material helps prevent the loss of thermal energy during induction heating by working as a thermal insulator. Further, ceramic material has a low coefficient of thermal expansion that helps inner tooling  304  and outer tooling  308  withstand the thermal gradients associated with the other components of consolidation setup  300  during induction heating. 
     In these illustrative examples, inner tooling  304  includes rods  316  embedded within this ceramic material. Rods  316  are positioned substantially parallel to longitudinal axis  301 . Further, rods  316  may be positioned circumferentially around longitudinal axis  301 . As seen in  FIG. 3 , rods  316  are positioned closer to longitudinal axis  301  than induction coils  313 . Rods  316  are an example of one implementation for rods  119  in  FIG. 2 . Rods  316  are fiberglass rods in these examples. Rods  316  being comprised of fiberglass, which is a dielectric material, helps rods  316  to provide compressive loading within inner tooling  304 . Rods  316  help put the ceramic material of inner tooling  304  in compression as the various components of consolidation setup  300  are added onto inner tooling  304 , which helps with the long-term durability of inner tooling  304 . In this manner, rods  316  reinforce inner tooling  304  and load inner tooling  108  during compression. 
     Stackup  306  is built up around inner tooling  304 . Outer tooling  308  is positioned around stackup  306 . In particular, outer tooling  308  is positioned around second smart susceptor  312 , which is positioned around stackup  306 . Similar to inner tooling  304 , outer tooling  308  may be comprised of a ceramic material. 
     In these illustrative examples, outer tooling  308  is comprised of two halves that are brought together around stackup  306 . For example, a fastener system (not shown) may be used to connect the two halves of outer tooling  308 . In some cases, load constraint  310  is used to hold the two halves of outer tooling  308  in place. Similarly, load constraint  310  may be comprised of two halves that are brought together around outer tooling  308  to secure outer tooling  308 , stackup  306 , and inner tooling  304  together. A fastener system (not shown) may be used to connect these two halves of load constraint  310 . In some cases, the same fastener system may be used to connect the two halves of both outer tooling  308  and load constraint  310 . The fastener system may include, for example, a clamping system (e.g., hydraulic clamps) that allows for easy clamping and easy release. In other illustrative examples, outer tooling  308 , load constraint  310 , or both may be a single cylindrical structure. 
       FIGS. 4-8  illustrate the buildup of stackup  306  from  FIG. 3  over inner tooling  304  in accordance with an example embodiment.  FIG. 4  is an illustration of a portion of inner tooling  304  from  FIG. 3  taken between lines  4 - 4  in  FIG. 3  in accordance with an example embodiment. First smart susceptor  311  is positioned around inner tooling  304  such that first smart susceptor  311  is positioned within the electromagnetic flux field generated by induction coils  118  when a current is run through induction coils  118 . 
     Bladder  400  is positioned over and around first smart susceptor  311 . Bladder  400  is an example of one implementation for bladder  202  in  FIG. 2 . Bladder  400  is the first component added to form stackup  306  from  FIG. 3 . Bladder  400  is an aluminum bladder in this illustrative example. During the induction consolidation process, bladder  400  is pressurized. Without pressurization, bladder  400  may be considered “deflated.” When pressure is applied to bladder  400 , bladder  400  may be considered “inflated.” Pressure may be applied to bladder  400  via an inert gas that flows through a pressurization tube (not shown in this view) extending through bladder  400  or a channel that extends through bladder  400 . 
     Bladder  400  includes recessed portions  402  formed between caps  404 . Recessed portions  402  are used to help index the locations for the fuselage stringers being formed. Recessed portion  406  is an example of one of recessed portions  402 . Recessed portion  406  is formed between cap  408  and cap  410  of caps  404 . 
     Recessed portion  406  is shaped such that recessed portion  406  includes main section  412 , stepped section  414 , and stepped section  415 . Stepped section  414  is located between main section  412  and cap  408  and stepped section  415  is located between main section  412  and cap  410 . Stepped section  414  has depth  416  and stepped section  415  has depth  418 . Depth  416  is measured as the distance between cap  408  and main section  412  and depth  418  is measured as the distance between cap  410  and main section  412 . Depth  416  and depth  418  are substantially equal in this illustrative example. 
     In this illustrative example, recessed portion  406  (i.e., main section  412 , stepped section  414 , and stepped section  415 ) is shaped to receive a caul that is shaped to form a “hat” stringer. For example, main section  412  may include base section  420  (forming the “cap” portion of the hat stringer) and web section  422  and web section  424  that extend from base section  420  to stepped section  414  and stepped section  415 , respectively. In other illustrative examples, recessed portion  406  may be shaped to receive some other type of caul. 
       FIG. 5  is an illustration of cauls added to stackup  306  from  FIG. 4  in accordance with an example embodiment. Cauls  500  are positioned within recessed portions  402  of bladder  400 . Cauls  500  are an example of one implementation for cauls  204  in  FIG. 2 . In particular, each of cauls  500  is positioned within a corresponding one of recessed portions  402 . 
     Further, each of cauls  500  is shaped such that the caul substantially conforms to or matches the shape of the corresponding recessed portion within which it is placed. In these illustrative examples, cauls  500  are shaped to enable the formation of “hat” stringers. 
     As previously described, cauls  500  may have a coefficient of thermal expansion that is sufficiently close to the coefficient of thermal expansion of overbraided thermoplastic members that will be later positioned over cauls  500  to thereby reduce or prevent undue stress from being introduced to the thermoplastic material. Cauls  500  are used to provide strength and rigidity during induction heating because bladder  400  softens during induction heating. 
     For example, caul  502  of cauls  500  is positioned within recessed portion  406 . Caul  502  is an example of one implementation for caul  228  in  FIG. 2 . Caul  502  is shaped to substantially conform to or match the shape of recessed portion  406 . Specifically, caul  502  is shaped to substantially match the shape of main section  412 , stepped section  414 , and stepped section  415  of recessed portion  406 . 
     For example, caul  502  includes main section  504 , flanged section  506 , and flanged section  508 . Main section  504  is shaped to fit securely within main section  412  of recessed portion  406 . As previously described, main section  412  forms at least a portion of a cross-sectional hat shape. Thus, similar to main section  412 , main section  504  similarly includes base section  510 , web section  512 , and web section  514 . Flanged section  506  and Flanged section  508  are shaped to sit securely within stepped section  414  and stepped section  415 , respectively, of recessed portion  406 . In this illustrative example, flanged section  506  has a thickness less than depth  416  of stepped section  414 . Flanged section  508  has a thickness less than depth  418  of stepped section  415 . 
       FIG. 6  is an illustration of overbraided thermoplastic members added to stackup  306  from  FIG. 5  in accordance with an example embodiment. Overbraided thermoplastic members  600  are positioned over cauls  500 . Overbraided thermoplastic members  600  are examples of implementations for overbraided thermoplastic members  206  in  FIG. 2 . Each of overbraided thermoplastic members  600  is positioned over a corresponding one of cauls  500 . 
     In some illustrative examples, overbraided thermoplastic members  600  are laid up directly over cauls  500  after cauls  500  have been added to stackup  306 . In other illustrative examples, overbraided thermoplastic members  600  may be added to stackup  306  at the same time as cauls  500 . For example, overbraided thermoplastic members  600  may be laid up over cauls  500  prior to being added to stackup  306 . Cauls  500  may then be used to transport and locate overbraided thermoplastic members  600  in the various recessed portions of bladder  400 . 
     Further, each of overbraided thermoplastic members  600  is substantially conformed to the shape of the corresponding caul. Overbraided thermoplastic members  600  will ultimately form “hat” stringers. 
     As one example, overbraided thermoplastic member  602  is positioned over caul  502 , which is positioned within recessed portion  406  of bladder  400 . Overbraided thermoplastic member  602  is substantially conformed to the shape of caul  502 . Specifically, overbraided thermoplastic member  602  is substantially conformed to the shape of main section  504 , flanged section  506 , and flanged section  508  of caul  502 . This shaping of overbraided thermoplastic member  602  results in overbraided thermoplastic member  602  having main section  604 , flanged section  606  and flanged section  608 . 
     In this illustrative example, flanged section  606  of overbraided thermoplastic member  602  and flanged section  506  of caul  502  have a combined thickness that is substantially equal to depth  416  of stepped section  414  of recessed portion  406  of bladder  400 . Similarly, flanged section  608  of overbraided thermoplastic member  602  and flanged section  508  of caul  502  have a combined thickness that is substantially equal to depth  418  of stepped section  415  of recessed portion  406  of bladder  400 . In this manner, overbraided thermoplastic member  602  does not extend past the circumferential profile of cap  408  or cap  410 . 
       FIG. 7  is an illustration of stringer bladders added to stackup  306  from  FIG. 6  in accordance with an example embodiment. Stringer bladders  700  are positioned over overbraided thermoplastic members  600 . Stringer bladders  700  are an example of one implementation for stringer bladders  208  in  FIG. 1 . Each of stringer bladders  700  is shaped to ensure that overbraided thermoplastic members  600  retain their desired shape for the formation of “hat” stringers. 
     Each of stringer bladders  700  is positioned over a corresponding one of overbraided thermoplastic members  600 . For example, stringer bladder  702  is positioned over overbraided thermoplastic member  602 . 
     In this illustrative example, stringer bladder  702  is shaped to ensure that overbraided thermoplastic member  602  maintains its shape during heating. Together, recessed portion  406  of bladder  400 , caul  502 , and stringer bladder  702  support both sides of overbraided thermoplastic member  602 , while securing overbraided thermoplastic member  602  in place. Stringer bladder  702  is shaped and sized such that side  704  of stringer bladder  702  follows the general circumferential outline formed by caps  404  of bladder  400 . 
     Similar to bladder  400 , stringer bladders  700  are pressurized during the induction consolidation process. Without pressurization, stringer bladders  700  may be considered “deflated.” Once pressurized, stringer bladders  700  may be considered “inflated.” 
       FIG. 8  is an illustration of an overbraided thermoplastic skin added to stackup  306  from  FIG. 7  in accordance with an example embodiment. Overbraided thermoplastic skin  800  is positioned over caps  404  of bladder  400 , stringer bladders  700 , and selected portions of overbraided thermoplastic members  600 . In particular, overbraided thermoplastic skin  800  is positioned such that overbraided thermoplastic skin  800  contacts the flanged sections of overbraided thermoplastic members  600 . For example, overbraided thermoplastic skin  800  contacts flanged section  606  and flanged section  608  of overbraided thermoplastic member  602 . 
     In this illustrative example, overbraided thermoplastic skin  800  surrounds the entire circumference of the portion of stackup  306  formed by bladder  400 , cauls  500 , overbraided thermoplastic members  600 , and stringer bladders  700 . The addition of overbraided thermoplastic skin  800  completes the formation of stackup  306  in these illustrative examples. 
       FIG. 9  is an illustration of second smart susceptor  312  and outer tooling  308  positioned around stackup  306  from  FIG. 8  in accordance with an example embodiment. Second smart susceptor  312  is positioned around overbraided thermoplastic skin  800 . Outer tooling  308  is positioned around second smart susceptor  312 . This placement ensures that second smart susceptor  312  is positioned within the electromagnetic flux field generated by induction coils  314  when a current is run through induction coils  314 . 
     Through induction coils  313  and induction coils  314 , first smart susceptor  311  and second smart susceptor  312  are used to heat and cause consolidation of overbraided thermoplastic skin  800  and overbraided thermoplastic members  600 . This consolidation results in a final fuselage structure comprised of a fuselage skin with integrated fuselage stringers. 
       FIG. 10  is an illustration of a longitudinal cross-sectional view of a system for supporting consolidation setup  300  during consolidation in accordance with an example embodiment. This cross-sectional view of system  1000 , and thereby consolidation setup  300 , is taken alone a plane substantially parallel to longitudinal axis  301 . In particular, this cross-sectional view is taken with respect to lines  10 - 10  in  FIG. 3A  and includes additional components that were not shown in  FIG. 3A . System  1000  is an example of one implementation for system  113  in  FIG. 1 . 
     As depicted in  FIG. 10 , stackup  306  has first end  1002  and second end  1004 . System  1000  includes a plurality of plugs  1005  for use in plugging these ends. In particular, plug  1006  and plug  1008  are used to plug first end  1002  and second end  1004 , respectively, of stackup  306 . 
     Plugs  1005  help ensure that the various components of stackup  306  remain in place during induction heating. For example, plugs  1005  do not expand longitudinally to the extent that bladder  400  and stringer bladders  700  may expand to thereby reduce undesired longitudinal expansion of bladder  400  and stringer bladders  700 . For example, plugs  1005  may not expand at all or may expand only slightly as compared to bladder  400  and stringer bladders  700 . The sizing of plugs  1005  may be selected to help ensure that the various components of stackup  306  remain in place during induction heating. 
     Further, plugs  1005  provide an easy and efficient way of loading and unloading components in system  1000 . Plugs  1005  may be removed to allow the various components of stackup  306  to be unloaded longitudinally. For example, bladder  400  and stringer bladders  700  may be slid out of system  1000  in a longitudinal direction when plugs  1005  are removed. 
     System  1000  further includes end tooling  1010  that is used to locate and secure plug  1006  and plug  1008 . End tooling  1010  may be, for example, a structural frame or system that helps secure plug  1006  and plug  1008  in place relative to stackup  306 . 
     Connector devices  1012  are used to connect induction coils  313  to induction coils  314 . In one illustrative example, each of connector devices  1012  is used to connect one of induction coils  313  embedded within inner tooling  304  to a corresponding one of induction coils  314  embedded within outer tooling  308  at a particular end of consolidation setup  300 . In some illustrative examples, each of connector devices  1012  is a knife switch connection. For example, each of connector devices  1012  may include a bar of copper or some other highly conductive material that is capable of rotating about a fixed pivot point. 
     In this example, connector devices  1012  include connector device  1014 , connector device  1016 , connector device  1018 , and connector device  1020 . Connector device  1014  connects coil  1022  of induction coils  313  with coil  1024  of induction coils  314  at end  1026  of consolidation setup  300 . Connector device  1016  connects coil  1022  with coil  1024  at end  1028  of consolidation setup  300 . Connector device  1018  connects coil  1030  of induction coils  313  with coil  1032  of induction coils  314  at end  1026  of consolidation setup  300 . Connector device  1020  connects coil  1030  with coil  1032  at end  1028  of consolidation setup  300 . 
     In some illustrative examples, consolidation setup  300  further includes pressure bladders  1038 . Each of pressure bladders  1038  is used to apply pressure at a corresponding one of plugs  1005 . Pressure bladder  1040  is an example of one of pressure bladders  1038 . Pressure bladder  1040  is used to apply pressure to in a manner that improves the electrical contact between first smart susceptor  311  and second smart susceptor  312  (not labeled in this view) and connector device  1014 . Pressure bladder  1040  may take the form of a stainless-steel bladder. 
       FIG. 11A  is an illustration of a portion of consolidation setup  300  from  FIG. 10  in which plug  1006  and plug  1008  are more clearly seen in accordance with an example embodiment. In this view, caul  502  is visible. Stringer bladder  702  located within the recessed portion of caul  502  is also present but not shown in this view. Further, this cross-sectional view is taken so that 
     Plug  1006  and plug  1008  are used to plug first end  1002  and second end  1004  of stackup  306 . Plug  1006  and plug  1008  are implemented similarly. In these examples, plug  1006  includes plug portion  1100 , thermal insulation layer  1102 , and susceptor connector  1104 . Plug  1008  similarly includes plug portion  1106 , thermal insulation layer  1108 , and susceptor connector  1110 . 
     Thermal insulation layer  1102  and thermal insulation layer  1108  provide a way of insulating susceptor connector  1104  and susceptor connector  1110 , respectively. These thermal insulation layers may be comprised of, for example, a dielectric material. In these examples, susceptor connector  1104  and susceptor connector  1110  are water-cooled susceptor connectors. If susceptor connector  1104  and susceptor connector  1110  were to get too hot, undesired heating, oxide buildup, or both might occur. Thus, susceptor connector  1104  and susceptor connector  1110  are water-cooled to prevent overheating. 
     Pressurization tube  1112  is an example of one implementation for one of pressurization tubes  238  in  FIG. 2 . In these illustrative examples, pressurization tube  1112  extends through stringer bladder  702  of stackup  306  (not shown in this view), past both ends of stringer bladder  702 , and out from both first end  1002  and second end  1004  of stackup  306 . As depicted, pressurization tube  1112  includes end  1114  and end  1116 . In these examples, end  1114  and end  1116  of pressurization tube  1112  extends into plug portion  1100  and plug portion  1106 , respectively, but do not extend past these plug portions. In other words, the ends of pressurization tube  1112  do not extend into thermal insulation layer  1102  or thermal insulation layer  1108 . In some cases, however, the ends of pressurization tube  1112  may extend all the way through and past plug  1006  and plug  1008 . 
     A pressurization system (not shown) may be used to cause an inert gas to flow through pressurization tube  1112  and into stringer bladder  702  (not shown in this view). For example, both end  1114  and end  1116  may be open and connected to tubing that is connected to the pressurization system to allow the inert gas to flow into pressurization tube  1112 . Pressurization tube  1112  may be implemented in various ways. 
       FIG. 11B  is an illustration of an enlarged view of one configuration for pressurization tube  1112  from  FIG. 11A  in accordance with an example embodiment. In  FIG. 11B , caul  502  from  FIG. 11  is not shown such that stringer bladder  702  nested within caul  502  may be more clearly seen. In this illustrative example, pressurization tube  1112  is a discontinuous pressurization tube that enters stringer bladder  702  without extending all the way through stringer bladder  702 . 
     In particular, pressurization tube  1112  includes opening  1118  and opening  1120  that open into stringer bladder  702 . In this manner, the inert gas flowing within pressurization tube  1112  may flow out of pressurization tube  1112  and directly into stringer bladder  702  via opening  1118  and opening  1120  to thereby pressurize stringer bladder  702 . Opening  1118  and opening  1120  may be sized according to pressurization requirements. 
       FIG. 11C  is an illustration of an enlarged view of another configuration for pressurization tube  1112  from  FIG. 11A  in accordance with an example embodiment. In  FIG. 11C , caul  502  from  FIG. 11  is not shown such that stringer bladder  702  nested within caul  502  may be more clearly seen. In this illustrative example, pressurization tube  1112  is a continuous tube that extends all the way through stringer bladder  702 . In this example, pressurization tube  1112  has one or more openings  1122  that enable the inert gas to flow out of pressurization tube  1112  and into stringer bladder  702  to thereby pressurize stringer bladder  702 . Openings  1122  may take different forms. For example, openings  1122  may be slits, perforations, holes, or some other type of opening in pressurization tube  1112 . 
       FIG. 11D  is an illustration of an enlarged view of yet another configuration for pressurization tube  1112  from  FIG. 11A  in accordance with an example embodiment. In  FIG. 11D , caul  502  from  FIG. 11  is not shown such that stringer bladder  702  nested within caul  502  may be more clearly seen. In this illustrative example, pressurization tube  1112  is a multitube pressurization tube. 
     In particular, pressurization tube  1112  includes first tube  1123  and second tube  1124 . First tube  1123  is a discontinuous tube that enters stringer bladder  702  and having end  1126  and end  1128  that terminate within stringer bladder  702 . Second tube  1124  is a continuous tube located within first tube  1123  that extends from end  1114  to end  1116 . For example, second tube  1124  has a smaller diameter than first tube  1123  and may be comprised of a harder material than pressurization tube  1112  to provide structural support to second tube  1124 . In one example, first tube  1123  is comprised of aluminum and second tube  1124  is comprised of stainless steel. Second tube  1124  has one or more openings  1130  (e.g., perforations, slits, holes, etc.) that allow an inert gas flowing through second tube  1124  to enter stringer bladder  702 . 
     The inert gas flows into stringer bladder  702  to pressurize stringer bladder  702  and thereby ensure expansion of stringer bladder  702 . This expansion helps ensure compression against provide a smooth, well-defined surface for overbraided thermoplastic member  602  shown in  FIGS. 7-9 . 
       FIG. 12  is an illustration of a cross-sectional view of stackup  306  taken with respect to lines  12 - 12  in  FIG. 11  in accordance with an example embodiment. In this illustrative example, stringer bladder  702  is not shown so, thereby making plug portion  1100  visible. 
     Channel  1200  extends through stringer bladder  702  and through plug portion  1100  of plug  1008 . Channel  1200  is used to receive pressurization tube  1112  from  FIG. 11 . Channel  1202  extends through plug  1006  and through bladder  400  (not shown in this view). Channel  1202  is used to receive a pressure bladder or pressurization tube that is used to apply pressure to bladder  400  during the induction consolidation process. Channel  1202  may be located anywhere that facilitates gas delivery to bladder  400 . 
       FIGS. 13A and 13B  are illustrations of a tacking-trimming setup in accordance with an example embodiment.  FIG. 13A  is an illustration of an isometric view of tacking-trimming setup  1300 . The tacking-trimming setup  1300  may also be referred to as a tow tacking and trimming apparatus.  FIG. 13B  is an illustration of a cross-sectional view of tacking-trimming setup  1300 . This cross-sectional view of tacking-trimming setup  1300  is taken with respect to lines  13 B- 13 B in  FIG. 13A . The description below is in reference to both  FIGS. 13A and 13B . 
     Tacking-trimming setup  1300  may be used to create the “tacking” and “trimming” needed for each braided ply of an overbraided thermoplastic component, such as one of overbraided thermoplastic members  600  or overbraided thermoplastic skin  800  in  FIGS. 6-10 . 
     In this illustrative example, tacking-trimming setup  1300  includes tacking-trimming system  1301 . Tacking-trimming system  1301  is secured to support system  1302  which surrounds surface  1304 . In these illustrative examples, tacking-trimming system  1301  may be secured to support system  1302  using a fastener system, a clamping system, a mounting structure, some other type of attachment device, or a combination thereof. Braided layup  1306 , which may be an example of one type of braided structure, is positioned around surface  1304 . Braided layup  1306  may be a layup of plies of overbraided continuous thermoplastic composite fibers. Conductive component  1308  is positioned around braided layup  1306 . 
     Although only one tacking-trimming system  1301  is shown secured to support system  1302 , any number of tacking-trimming systems may be distributed along support system  1302 . In these illustrative examples, support system  1302  includes support ring  1303 . Support ring  1303  is sized and shaped to fully surround surface  1304 . 
     Support system  1302  travels with a braiding ring or braider (not shown in this view) to enable the adding and dropping of plies in a direction along longitudinal axis  1307  to create and add to braided layup  1306 . In other words, plies may be added and dropped longitudinally. Further, support system  1302  may rotate about longitudinal axis  1307  or tacking-trimming system  1301  may move around support system  1302  to enable the adding and dropping-of plies around surface  1304  circumferentially. Conductive component  1308 , which may also be referred to as a “shoe,” also travels with the braiding ring or braider. 
     In one illustrative example, surface  1304  may be the surface formed by bladder  400 , stringer bladders  700 , and overbraided thermoplastic members  600  in  FIG. 7  before overbraided thermoplastic skin  800  from  FIG. 8  is added. In this example, overbraided thermoplastic skin  800  is laid up over surface  1304  as braided layup  1306 . Tacking-trimming system  1301  may be used to tack weld and trim during or after the layup of overbraided thermoplastic skin  800 . 
     In other illustrative examples, surface  1304  may be the surface formed by cauls  500 . In these examples, overbraided thermoplastic members  600  from  FIG. 6  are laid up over surface  1304  to form braided layup  1306 . Tacking-trimming system  1301  may be used to tack weld and trim during or after the layup of overbraided thermoplastic members  600  but prior to the consolidation of overbraided thermoplastic members  600  with overbraided thermoplastic skin  800 . In some cases, when overbraided thermoplastic members  600  in  FIG. 6  are transported to stackup  306  via cauls  500 , tacking-trimming system  1301  may be used to tack weld and trim the already formed layup of overbraided thermoplastic members  600 . For example, support system  1302  may be sized and shaped to operatively place tacking-trimming system  1301  relative to stackup  306 , which may also be referred to as a cylindrical thermoplastic stackup. 
     Tack welding may be performed longitudinally, circumferentially, or both. Further, tack welding may be used to add and drop plies in a manner that allows complicated preform structures to be formed. For example, braided layup  1306  may include a plurality of plies that are not all continuous layers. Some plies may be partial layers. In some cases, braided layup  1306  includes padups and pad downs. Thus, braided layup  1306  may have varying thicknesses and contours along braided layup  1306 . Tack welding is used to help maintain the structural integrity of braided layup  1306 . 
     In still other illustrative examples, tacking-trimming system  1301  may be used to add local features to braided layup  1306 . For example, when braided layup  1306  takes the form of overbraided thermoplastic skin  800  in  FIG. 8 , tacking-trimming system  1301  may be used to tack weld and trim localized features (e.g., padups) that are added to overbraided thermoplastic skin  800 . 
     In this manner, tacking-trimming system  1301  may be used to provide and maintain a desired architecture for braided layup  1306 . In these illustrative examples, tacking-trimming system  1301  is used for tack welding and trimming prior to consolidation. But in other illustrative examples, tacking-trimming system  1301  may be used to tack weld and trim localized layup features that are added to an integrated structure (e.g., fuselage barrel section) that has already gone through at least one consolidation process. 
       FIG. 14  is an illustration of a cross-sectional view of a portion of tacking-trimming setup  1300  in  FIG. 13  in accordance with an example embodiment. This view of tacking-trimming setup  1300  is taken with respect to lines  14 - 14  in  FIG. 13 . 
     As depicted, tacking-trimming system  1301  is secured to support system  1302 . Tacking-trimming system  1301  includes tack welder  1400  and trimmer  1402 . Tack welder  1400  is positioned to help the laying up of thermoplastic tows along surface  1304  to form braided layup  1306  comprised of thermoplastic plies. Tow  1404  is an example of one of these thermoplastic tows being fed from a braiding ring or a braider. Tack welder  1400  is resistively heated and helps tack tow  1404  to braided layup  1306 . 
     Trimmer  1402  is used to trim tow  1404 . Trimmer  1402  may be, for example, without limitation, a laser trimmer. Conductive component  1308  is positioned between tow  1404  and braided layup  1306  to absorb the laser energy emitted by trimmer  1402  and thereby protect braided layup  1306 . Conductive component  1308  is thermally conductive in these examples. 
     The illustrations in  FIGS. 3-14  are not meant to imply physical or architectural limitations to the manner in which an illustrative embodiment may be implemented. Other components in addition to or in place of the ones illustrated may be used. Some components may be optional. 
     The different components shown in  FIGS. 3-14  may be illustrative examples of how components shown in block form in  FIGS. 1-2  may be implemented as physical structures. Additionally, some of the components in  FIGS. 3-14  may be combined with components in  FIGS. 1-2 , used with components in  FIGS. 1-2 , or both. 
       FIG. 15  is a flowchart of a process for forming a composite structure in accordance with an example embodiment. Process  1500  illustrated in  FIG. 15  may be performed using, for example, system  113  described in  FIG. 1  to form composite structure  101 . In some examples, consolidation setup  300  from  FIGS. 3-11  is used to form composite structure  101 . 
     Process  1500  begins by building a stackup that comprises a bladder having a plurality of recessed portions, a plurality cauls within the plurality of recessed portions, a plurality of overbraided thermoplastic members, a plurality of stringer bladders, and an overbraided thermoplastic skin, the stackup being positioned between an inner tooling and an outer tooling (operation  1502 ). The stackup, the inner tooling, and the outer tooling may be implemented in a manner similar to, for example, stackup  112 , inner tooling  108 , and outer tooling  110 , respectively, in  FIG. 1  or stackup  306 , inner tooling  304 , and outer tooling  308 , respectively, in  FIGS. 3-8 . 
     In some cases, with respect to operation  1502 , the stackup is built over the inner tooling component by component. The outer tooling is then secured over the stackup. In other cases, the stackup is pre-built and then positioned over the inner tooling prior to the outer tooling being positioned over the stackup. 
     Thereafter, a load constraint is positioned around the outer tooling such that the inner tooling, the stackup, the outer tooling, and the load constraint form a consolidation setup (operation  1504 ). The consolidation setup is heated inductively to consolidate the plurality of overbraided thermoplastic members to the overbraided thermoplastic skin, thereby forming a composite structure (operation  1506 ), with the process terminating thereafter. In particular, operation  1506  results in the formation of an integrated composite structure. 
     In some illustrative examples, operation  1506  may be performed by heating, inductively, a first smart susceptor located between the inner tooling and the stackup and a second smart susceptor located between the outer tooling and the stackup to cause consolidation of the plurality of overbraided thermoplastic members to the overbraided thermoplastic skin. This process forms a plurality of fuselage stringers integrated with a circumferential skin. The plurality of overbraided thermoplastic members form the fuselage stringers and the overbraided thermoplastic skin forms the circumferential skin form a composite fuselage structure, such as composite fuselage structure  102  in  FIG. 1 . 
       FIG. 16  is a flowchart of a process for building a stackup in accordance with an example embodiment. Process  1600  illustrated in  FIG. 16  may be performed to build, for example, stackup  112  described in  FIG. 1  or stackup  306  described in  FIGS. 3-8 . Further, process  1600  may be used to implement operation  1502  in  FIG. 15 . 
     Process  1600  begins by positioning a bladder around a first smart susceptor that surrounds an inner tooling (operation  1602 ). The bladder may be comprised of aluminum. In these illustrative examples, the first smart susceptor surround the inner tooling like a liner for the inner tooling. 
     Thereafter, a plurality of cauls is positioned within a plurality of recessed portions of the bladder (operation  1604 ). In these illustrative examples, each of the plurality of cauls is comprised of a nickel-iron alloy. In one illustrative example, each of the plurality of cauls is comprised of an invar alloy (e.g., Invar 52). 
     A plurality of overbraided thermoplastic members is then positioned over the plurality of cauls (operation  1606 ). In particular, each of the plurality of overbraided thermoplastic members is positioned over and within the recessed portion of a corresponding one of the plurality of cauls. Each of the plurality of overbraided thermoplastic members has a shape similar to the shape of the corresponding caul. The cauls help provide mechanical strength and rigidity during heating to help maintain the shape and smoothness of the plurality of overbraided thermoplastic members. 
     Next, a plurality of stringer bladders is positioned over the plurality of overbraided thermoplastic members (operation  1608 ). An overbraided thermoplastic skin is then positioned around the plurality of stringer bladders and plurality of overbraided thermoplastic members such that the overbraided thermoplastic skin contacts end sections of the plurality of overbraided thermoplastic members, the overbraided thermoplastic skin and the plurality of overbraided thermoplastic members forming the composite fuselage structure after inductive consolidation (operation  1610 ), with the process terminating thereafter. During the inductive consolidation, the overbraided thermoplastic skin is consolidated with or integrated with the overbraided thermoplastic members. The overbraided thermoplastic skin forms the fuselage skin and the overbraided thermoplastic members form the fuselage stringers for the composite fuselage structure. 
       FIG. 17  is a flowchart of a process for building a system that includes a consolidation setup in accordance with an example embodiment. Process  1700  illustrated in  FIG. 17  may be performed to build system  103  that includes consolidation setup  104  described in  FIG. 1  or system  1000  that consolidation setup  300  from  FIGS. 3-11 . 
     Process  1700  may begin by positioning a bladder around a first smart susceptor that surrounds an inner tooling (operation  1702 ). The inner tooling includes a plurality of induction coils embedded within the inner tooling. The inner tooling may be supported by a support structure. In these examples, the inner tooling has a circumferential shape (e.g., a cylindrical or near-cylindrical shape, a tapered cylindrical shape, a conical shape, etc.). In one illustrative example, the inner tooling is shaped such that any given cross-section along a longitudinal axis of the inner tooling has a substantially circular (circular or near-circular) shape. 
     In operation  1702 , the bladder may be an aluminum bladder that has a plurality of recessed portions. The bladder may be positioned around the first smart susceptor to surround the first smart susceptor, and thereby the inner tooling. 
     Cauls are positioned within the recessed portions of the bladder (operation  1704 ). In operation  1704 , the cauls may be comprised of a nickel-iron alloy, such as an invar alloy. Each caul is shaped to substantially conform to or match the shape of the corresponding recessed portion of the bladder within which that caul is positioned. In one illustrative example, the recessed portion of the bladder, and thereby the caul, has an upside-down hat shape. 
     Overbraided thermoplastic members are then positioned over the cauls (operation  1706 ). In operation  1706 , the overbraided thermoplastic members are shaped to substantially conform to or match the cauls. Thereafter, stringer bladders are positioned over the plurality of overbraided thermoplastic members (operation  1708 ). The stringer bladders are shaped to nest within the recessed portions or open spaces defined by the overbraided thermoplastic members. These stringer bladders may be comprised of aluminum in these illustrative examples. 
     The stringer bladders are surrounded with an overbraided thermoplastic skin such that the bladder, the cauls, the overbraided thermoplastic members, the stringer bladders, and the overbraided thermoplastic skin together form a stackup (operation  1710 ). In operation  1710 , the overbraided thermoplastic skin contacts at least portions of the overbraided thermoplastic members. These portions may be the flanged sections of the overbraided thermoplastic members. 
     A second smart susceptor is then positioned around the overbraided thermoplastic skin (operation  1712 ). Outer tooling is positioned around the second smart susceptor to form a consolidation setup (operation  1714 ). Similar to the inner tooling, the outer tooling includes a plurality of induction coils embedded within the outer tooling. A load constraint is then used to secure the outer tooling, the stackup, and the inner tooling (operation  1716 ). 
     Pressurization tubes are inserted through the bladder and the stringer bladders (operation  1718 ), with the process terminating thereafter. As one illustrative example, one pressurization tube may be inserted through a channel in the bladder, while multiple other pressurization tubes may be inserted through the stringer bladders (e.g., a single pressurization tube per stringer bladder). Thus, the consolidation setup includes the inner tooling, the stackup, the outer tooling, the load constraint, and the pressurization tubes. In other illustrative examples, the pressurization tubes may be considered separate from the consolidation setup. 
     Thereafter, first induction coils embedded in the inner tooling and second induction coils embedded in the outer tooling are connected via connector devices (operation  1720 ). These connector devices may take the form of, for example, knife switch connectors. The ends of the stackup are capped using plugs (operation  1722 ). The plugs are located and secured using end tooling (operation  1724 ), with the process terminating thereafter. 
       FIG. 18  is a flowchart of a process for building a system to form a composite fuselage structure in accordance with an example embodiment. Process  1800  illustrated in  FIG. 18  may be performed to build system  113  described in  FIG. 1 . 
     Process  1800  may begin by building a consolidation setup (operation  1802 ). Operation  1802  may be performed using, for example, process  1700  in  FIG. 17 . For example, the consolidation setup built in operation  1802  that includes an inner tooling embedded with first induction coils, an outer tooling embedded with second induction coils, a first smart susceptor, a second smart susceptor, and a stackup positioned between the first smart susceptor and the second smart susceptor, the stackup including a plurality of overbraided thermoplastic members and an overbraided thermoplastic skin. 
     Next, the consolidation setup is heated inductively using the first induction coils, the second induction coils, the first smart susceptor, and the second smart susceptor to thereby consolidate the overbraided thermoplastic skin with the plurality of overbraided thermoplastic members to form the composite fuselage structure (operation  1804 ), with the process terminating thereafter. 
       FIG. 19  is a flowchart of a process for inductively consolidating an overbraided thermoplastic skin with overbraided thermoplastic members to form a composite fuselage structure in accordance with an example embodiment. Process  1900  illustrated in  FIG. 19  may be performed to inductively consolidate, for example, overbraided thermoplastic skin  210  with overbraided thermoplastic members  206  from  FIG. 2 . Further, process  1900  may be implemented using system  103 , which includes consolidation setup  104  that includes stackup  112 , as described in  FIG. 1-2 . 
     Process  1900  begins by connecting first induction coils embedded in the inner tooling of a consolidation setup with second induction coils embedded in the outer tooling of the consolidation setup (operation  1902 ). Operation  1902  may be performed using connector devices such as connector devices  107  in  FIG. 1 . In one or more illustrative examples, the first induction coils and the second induction coils may be connected to ultimately form an annular-shaped solenoid coil. 
     Thereafter, a selected amount of pressure is applied to the bladder in the consolidation setup (operation  1904 ). For example, in operation  1904 , a pressurization system may be connected to the bladder and may use inert gas to apply the pressure. In one illustrative example, the pressurization system pressurization tube located within the bladder or to a channel that extends through the bladder. The pressurization system may use inert gas to apply the pressure. In operation  1904 , the amount of pressure applied may be small (e.g., about 15 psi). 
     The first induction coils and the second induction coils are energized to heat the first smart susceptor and the second smart susceptor in the consolidation setup and thereby heat the thermoplastic material in the consolidation setup to within selected tolerances of a selected temperature (operation  1906 ). The selected temperature may be, for example, a temperature above 350 degrees Fahrenheit. In operation  1906 , the thermoplastic material may be the overbraided thermoplastic skin and the overbraided thermoplastic members of the stackup that will form the fuselage skin and fuselage stringers, respectively, of the composite fuselage structure. 
     Pressure is applied via the bladder and the stringer bladders (operation  1908 ). Operation  1908  may be performed by, for example, using the pressurization system to apply about pressure of about 250 psi to help smooth out the thermoplastic material. Operation  1908  is the step at which inductive consolidation of the overbraided thermoplastic skin to the overbraided thermoplastic members occurs and a composite fuselage structure is formed. This composite fuselage structure may be, for example, a fuselage barrel section. The temperature of the thermoplastic material is then reduced (operation  1910 ). The pressure is reduced when the temperature has reached below a selected threshold (operation  1912 ). For example, in operation  1912 , the pressure may be reduced to about 15 psi once the temperature has dropped below about 300 degrees Fahrenheit. 
     Thereafter, the composite fuselage structure is unloaded (operation  1914 ). A vacuum is applied to the bladder to create a gap between the composite fuselage structure and the inner tooling of the consolidation setup (operation  1916 ). The outer tooling of the consolidation setup is removed, allowing the composite fuselage structure to be removed from the inner tooling (operation  1918 ), with the process terminating thereafter. 
     In other illustrative examples, process  1900  includes additional operations for customizing the composite fuselage structure once the composite fuselage structure has been removed from the inner tooling. For example, cutouts may be added to the composite fuselage structure and other components may be added to the composite fuselage structure. In one illustrative example, window belt cutouts are added. In other examples, fuselage and window frames are added using induction joining or induction welding techniques. Induction joining or induction welding may also be used to add parts such as, for example, without limitation, shear ties, systems brackets, antenna reinforcements, service pan reinforcements, other types of parts, or a combination thereof, to the composite fuselage structure. 
       FIG. 20  is a flowchart for forming a composite structure in accordance with an example embodiment. Process  2000  illustrated in  FIG. 20  may be performed to form a composite structure such as composite structure  101  in  FIG. 1 . 
     Process  2000  begins by holding an inner tooling, a stackup, and an outer tooling in place together using a load constraint (operation  2002 ). A bladder and a plurality of stringer bladders in the stackup are pressurized to cause expansion of the bladder and the plurality of bladders, thereby pushing together the overbraided thermoplastic skin and the plurality of overbraided thermoplastic members (operation  2004 ). 
     Thereafter, an overbraided thermoplastic skin and a plurality of overbraided thermoplastic members are co-consolidated in the stackup while the bladder and the plurality of stringer bladders are pressurized to form the composite structure (operation  2006 ), with the process terminating thereafter. The pressurization provided in operation  2004  ensures that co-consolidation of the overbraided thermoplastic skin and the plurality of overbraided thermoplastic members occurs evenly and smoothly. 
       FIG. 21  is a flowchart for forming a composite fuselage structure in accordance with an example embodiment. Process  2100  illustrated in  FIG. 21  may be performed to form a composite structure such as composite structure  101  in  FIG. 1 . 
     Process  2100  begins by expanding a bladder and a plurality of stringer bladders in a stackup to place fibers in an overbraided thermoplastic skin and a plurality of overbraided thermoplastic members in tension (operation  2102 ). Operation  2102  may be performed by, for example, pressurizing the bladder and the plurality of stringer bladders. In some examples, the bladder and the stringer bladders are pressurized using pressurization tubes through which inert gas flows. The pressurization tubes may be expanded via the addition of inert gas, which may lead to expansion of the bladder and stringer bladders. 
     The stackup is heated to melt the overbraided thermoplastic skin and the plurality of overbraided thermoplastic members (operation  2104 ). Operation  2104  may be performed using induction-based smart susceptor heating. The overbraided thermoplastic skin and the plurality of overbraided thermoplastic members are then joined together while the overbraided thermoplastic skin and the plurality of overbraided thermoplastic members are melted (operation  2106 ). The stackup is cooled such that the overbraided thermoplastic skin and the plurality of overbraided thermoplastic members form an integrated structure that is the composite fuselage structure (operation  2108 ), with the process terminating thereafter. 
       FIG. 22  is a flowchart for forming a composite structure in accordance with an example embodiment. Process  2200  illustrated in  FIG. 22  may be performed to form a composite structure such as composite structure  101  in  FIG. 1 . 
     Process  2200  begins by building a stackup comprising a plurality of overbraided thermoplastic members and an overbraided thermoplastic skin (operation  2202 ). The stackup is placed between an inner tooling and an outer tooling (operation  2204 ). The inner tooling, the stackup, and the outer tooling are held in place together using a load constraint, with the inner tooling, the stackup, the outer tooling, and the load constraint forming a consolidation setup (operation  2206 ). The consolidation setup is heated to form the composite structure (operation  2208 ), with the process terminating thereafter. 
       FIG. 23  is an illustration of a process for forming a composite structure in accordance with an example embodiment. Process  2300  illustrated in  FIG. 23  may be performed to form a composite structure such as composite structure  101  in  FIG. 1 . 
     Process  2300  may include forming a plurality of consolidated overbraided thermoplastic preforms (operation  2302 ). The plurality of consolidated overbraided thermoplastic preforms may include a plurality of overbraided thermoplastic members and an overbraided thermoplastic skin. Further, process  2300  includes co-consolidating the plurality of consolidated overbraided thermoplastic preforms in a circumferential stackup that is circumferentially constrained (operation  2304 ). The fibers of the plurality of consolidated overbraided thermoplastic preforms are tensioned during co-consolidation (operation  2306 ). 
     In process  2300 , operation  2304  is performed without the use of an autoclave. In operation  2304 , bladders are used to react against the outer load constraint and provide the pressure that would have typically been provided using an autoclave. Further, in operation  2304 , induction coils and smart susceptors are used to provide the heat that would have typically been provided using an autoclave. 
       FIG. 24  is an illustration of a process for forming a composite structure in accordance with an example embodiment. Process  2400  illustrated in  FIG. 24  may be performed to form a composite structure such as composite structure  101  in  FIG. 1 . 
     Process  2400  begins by expanding a plurality of stringer bladders in a stackup to thereby apply force against a plurality of overbraided thermoplastic members and an overbraided thermoplastic skin (operation  2402 ). Operation  2402  may be performed by heating the plurality of stringer bladders and pressurizing the plurality of stringer bladders via an inert gas that flows from a plurality of pressurization tubes into the plurality of stringer bladders. The expansion of the plurality of stringer bladders tensions the plurality of overbraided thermoplastic members and helps resist compressive loading on the plurality of overbraided thermoplastic members. 
     The stackup is constrained via a dielectric material embedded within a non-dielectric material during expansion of the plurality stringer bladders (operation  2404 ). Operation  2404  may be performed by compressing the stackup against an outer tooling comprising the dielectric material. The dielectric material is a ceramic material and the non-dielectric material may be a plurality of induction coils used for the heating performed in operation  2402 . The non-dielectric material is constrained via the dielectric material during the expansion of the plurality of stringer bladders (operation  2406 ). 
       FIG. 25  is a flowchart of a process for tacking and trimming a thermoplastic tow in accordance with an example embodiment. The process illustrated in  FIG. 25  may be used to tack and trim the thermoplastic tows that ultimately form overbraided thermoplastic skin  210  and overbraided thermoplastic members  206  in  FIG. 2 . 
     Process  2500  begins by laying up a thermoplastic tow received from a braiding ring over a braided structure on a surface, a portion of the thermoplastic tow being received over a conductive component (operation  2502 ). The thermoplastic tow may be an overbraided thermoplastic tow. The surface may be formed by at least one of a tooling surface, a caul, a bladder, a stringer bladder, a partially-formed braided layup, a preform, an integrated composite structure, or some other type of surface. The braided structure may be, for example, a braided layup of overbraided thermoplastic material, a partially-formed braided layup, a preform, an integrated structure made of overbraided thermoplastic material, or some other type of braided structure. In operation  2502 , the thermoplastic tow may be positioned over the braided structure being formed on the surface. The conductive component in operation  2502  may be referred to as a “shoe.” 
     A tack welder secured to a support ring is then used to tack weld the thermoplastic tow to the braided structure (operation  2504 ). In operation  2504 , the tack welder is resistively heated to ensure even tacking of the thermoplastic tow to the braided structure. A portion of the thermoplastic tow is trimmed to thereby trim the thermoplastic tow received over the braided structure (operation  2506 ), with the process terminating thereafter. In operation  2506 , laser energy is applied to the portion of the thermoplastic tow supported by a conductive component to trim the thermoplastic tow. The conductive component absorbs the laser energy to protect the braided structure below the conductive component. 
       FIG. 26  is a flowchart of a process for tacking and trimming a thermoplastic tow in accordance with an example embodiment. The process illustrated in  FIG. 26  may be used to tack and trim the thermoplastic tows that ultimately form overbraided thermoplastic skin  210  and overbraided thermoplastic members  206  in  FIG. 2 . 
     Process  2600  begins by laying up a thermoplastic tow received from a braiding system over a braided structure on a surface (operation  2602 ). The received thermoplastic tow is tack welded to the braided structure (operation  2604 ). The thermoplastic tow is trimmed by applying laser energy to a portion of the received thermoplastic tow (operation  2606 ), with the process terminating thereafter. 
     Example embodiments of the disclosure may be described in the context of aircraft manufacturing and service method  2700  as shown in  FIG. 27  and aircraft  2800  as shown in  FIG. 28 . Turning first to  FIG. 27 , an illustration of an aircraft manufacturing and service method is depicted in accordance with an illustrative embodiment. During pre-production, aircraft manufacturing and service method  2700  may include specification and design  2702  of aircraft  2800  in  FIG. 28  and material procurement  2704 . 
     During production, component and subassembly manufacturing  2706  and system integration  2708  of aircraft  2800  in  FIG. 28  takes place. Thereafter, aircraft  2800  in  FIG. 28  may go through certification and delivery  2710  in order to be placed in service  2712 . While in service  2712  by a customer, aircraft  2800  in  FIG. 28  is scheduled for routine maintenance and service  2714 , which may include modification, reconfiguration, refurbishment, and other maintenance or service. 
     Each of the processes of aircraft manufacturing and service method  2700  may be performed or carried out by a system integrator, a third party, and/or an operator. In these examples, the operator may be 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, a leasing company, a military entity, a service organization, and so on. 
     With reference now to  FIG. 28 , an illustration of an aircraft is depicted in which an illustrative embodiment may be implemented. In this example, aircraft  2800  is produced by aircraft manufacturing and service method  2700  in  FIG. 27  and may include airframe  2802  with plurality of systems  2804  and interior  2806 . Examples of systems  2804  include one or more of propulsion system  2808 , electrical system  2810 , hydraulic system  2812 , and environmental system  2814 . Any number of other systems may be included. Although an aerospace example is shown, different illustrative embodiments may be applied to other industries, such as the automotive industry. 
     Apparatuses and methods embodied herein may be employed during at least one of the stages of aircraft manufacturing and service method  2700  in  FIG. 27 . In particular, system  103  from  FIGS. 1-2  may be used to form composite structure  101  during any one of the stages of aircraft manufacturing and service method  2700 . For example, without limitation, system  103  from  FIGS. 1-2  may be used to form composite structure  101  during at least one of component and subassembly manufacturing  2706 , system integration  2708 , routine maintenance and service  2714 , or some other stage of aircraft manufacturing and service method  2700 . Still further, system  103  from  FIGS. 1-2  may be used to form at least a portion of airframe  2802  of aircraft  2800  in  FIG. 28 . For example, system  103  may be used to form a fuselage barrel section of airframe  2802 . 
     In one illustrative example, components or subassemblies produced in component and subassembly manufacturing  2706  in  FIG. 27  may be fabricated or manufactured in a manner similar to components or subassemblies produced while aircraft  2800  is in service  2712  in  FIG. 27 . As yet another example, one or more apparatus embodiments, method embodiments, or a combination thereof may be utilized during production stages, such as component and subassembly manufacturing  2706  and system integration  2708  in  FIG. 27 . One or more apparatus embodiments, method embodiments, or a combination thereof may be utilized while aircraft  2800  is in service  2712  and/or during maintenance and service  2714  in  FIG. 27 . The use of a number of the different illustrative embodiments may substantially expedite the assembly of and/or reduce the cost of aircraft  2800 . 
     The flowcharts and block diagrams in the different depicted embodiments illustrate the architecture, functionality, and operation of some possible implementations of apparatuses and methods in an example embodiment. In this regard, each block in the flowcharts or block diagrams may represent a module, a segment, a function, and/or a portion of an operation or step. 
     In some alternative implementations of an example embodiment, the function or functions noted in the blocks may occur out of the order noted in the figures. For example, in some cases, two blocks shown in succession may be executed substantially concurrently, or the blocks may sometimes be performed in the reverse order, depending upon the functionality involved. Also, other blocks may be added in addition to the illustrated blocks in a flowchart or block diagram. 
     As used herein, the phrase “at least one of,” when used with a list of items, means different combinations of one or more of the listed items may be used and only one of the items in the list may be needed. The item may be a particular object, thing, step, operation, process, or category. In other words, “at least one of” means any combination of items or number of items may be used from the list, but not all of the items in the list may be required. For example, without limitation, “at least one of item A, item B, or item C” or “at least one of item A, item B, and item C” may mean item A; item A and item B; item B; item A, item B, and item C; item B and item C; or item A and C. In some cases, “at least one of item A, item B, or item C” or “at least one of item A, item B, and item C” may mean, but is not limited to, two of item A, one of item B, and ten of item C; four of item B and seven of item C; or some other suitable combination. 
     The description of the different example embodiments has been presented for purposes of illustration and description, and is not intended to be exhaustive or limited to the embodiments in the form disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art. Further, different example embodiments may provide different features as compared to other desirable embodiments. The embodiment or embodiments selected are chosen and described in order to best explain the principles of the embodiments, the practical application, and to enable others of ordinary skill in the art to understand the disclosure for various embodiments with various modifications as are suited to the particular use contemplated.