Abstract:
A universal adapter system and method for coupling payloads and launch vehicles are disclosed to provide optimum payload configurability. A modular bulkhead panel may be used that can support a plurality of payload platforms such that the layout of the plurality of payload platforms on the bulkhead panel can be altered without requiring structural redesign. A carbon composite honeycomb structural frame panel may be used. Multiple bulkhead panels can be stacked to handle larger payload weights. Hollow hexagonal keyways can be used to permit cable access to and from a missile deployment module. Hexagonal payload adapter platforms may be used to join the payload to the honeycomb bulkhead panel.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates to aerospace structures. Particularly, this invention relates to launch vehicle payload support structures, such as adapters attaching a payload to a missile. 
     2. Description of the Related Art 
     Every aerospace launch vehicle, e.g., missile or rocket, must be coupled to its payload, e.g., weapon or commercial satellite. It is typical that a particular launch vehicle may be used with a range of payload types. However, under a conventional approach, a unique structural platform is designed for every unique payload to secure it to the launch vehicle or booster rocket. Thus, for every payload that may be employed with a given missile system—those currently existing and yet to be developed—a like number of payload platforms must be developed. 
     The requirement of a custom structural adapter design for every payload configuration can negatively impact hardware development. The new components require additional schedule to design, manufacture and test. In addition, developing new hardware also carries an increased risk of a failure, either in development or when it is first used. Of course, all of these factors bring additional costs. 
     Furthermore, there may be mission scenarios that will require the implementation of two or more different payloads, of varying weights and dimensions, on the same flight. For these mission scenarios it can become extremely expensive, if not impossible, to develop unique adapters to accommodate every possible payload permutation ahead of time. 
     In one example prior art system, the Minuteman rocket uses a payload attachment kit that provides the electrical and mechanical means to attach a single reentry vehicle to a standard payload bulkhead support assembly. The kit contains support fittings that mechanically attach the reentry vehicles to the bulkhead and is designed for only a limited number of payload configurations. Alternate configurations not covered by the kit require the design and development of costly new attachment kits that would take months, if not years, to ultimately produce. 
     In view of the foregoing, there is a need in the art for apparatuses and methods for structural coupling a wide range payloads to a common launch vehicle or booster rocket. Further, there is a need for such systems and methods to accommodate coupling multiple payloads to a single launch vehicle. Particularly, there is a need for such systems and methods to facilitate the development of structural interfaces without requiring excessive additional cost or schedule. These and other needs are met by the present invention as detailed hereafter. 
     SUMMARY OF THE INVENTION 
     A universal adapter system and method for coupling payloads and launch vehicles are disclosed to provide optimum payload configurability. Embodiments of the invention can use a modular bulkhead panel that can support a plurality of payload platforms such that the layout of the plurality of payload platforms on the bulkhead panel can be altered without requiring structural redesign. A carbon composite honeycomb structural frame panel may be used. Multiple bulkhead panels can be stacked to handle larger payload weights. Hollow hexagonal keyways can be used to permit cable access to and from a missile deployment module. Hexagonal payload adapter platforms may be used to join the payload to the honeycomb bulkhead panel. 
     A typical embodiment of the invention comprises a launch vehicle interface, including a bulkhead panel for being secured to a launch vehicle, a keyway pattern in the bulkhead panel for receiving a matching key pattern attached to one or more payload platforms, and an insert pattern of structural inserts in the bulkhead panel for securing the one or more payload platforms. The structural inserts may comprise threaded inserts, each for receiving a bolt for securing the one or more payload platforms. The bulkhead panel may be a honeycomb panel structure, made of a composite material for example. The honeycomb panel structure may be constructed as a hexagonal grid such that each of the structural inserts is positioned in each segment of the hexagonal grid. 
     Embodiments of the invention create a modular structure that can support a plurality of payload panels such that the layout of the plurality of payload panels can be altered at will without requiring structural redesign. In one example, the one or more payload panels can support one or more satellites for a particular mission. The one or more payload panels may be used to support one or more payload support systems and as well as one or more payloads. For example, a telemetry control unit and/or a global positioning system (GPS) unit may be positioned on the bulkhead panel on their own payload panels along with one or more satellite or weapon payloads, each on their own payload panels. 
     In further embodiments, one or more structural keyways of the keyway pattern may also be used as cable pathways for routing one or more support cables, routing electrical cables between payload components and the launch vehicle for example. Furthermore, in some embodiments one or more additional bulkhead panels may be stacked on the bulkhead panel to support additional payload weight. 
     Similarly, a typical method embodiment of the invention for coupling a payload to a launch vehicle may include the steps of securing a bulkhead panel to a launch vehicle, the bulkhead panel having a keyway pattern, receiving a matching key pattern into the keyway pattern, the matching key pattern being attached to one or more payload platforms, and securing the one or more payload platforms to the bulkhead panel by an insert pattern of structural inserts in the bulkhead panel. The method may be further modified consistent with the apparatus and system embodiments described herein. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Referring now to the drawings in which like reference numbers represent corresponding parts throughout: 
         FIG. 1  illustrates a launch vehicle and interface to a payload; 
         FIG. 2A  illustrates an exemplary bulkhead panel for an embodiment of the invention; 
         FIG. 2B  illustrates a plurality of bulkhead panels for an embodiment of the invention; 
         FIGS. 3A &amp; 3B  illustrate an exemplary payload platform for coupling to a bulkhead panel; 
         FIG. 4  illustrates keyways and keys used to couple payload platforms to a bulkhead panel; 
         FIGS. 5A &amp; 5B  illustrate an exemplary bulkhead structure and mechanical interface; 
         FIGS. 6A to 6E  illustrates some exemplary platform configurations for embodiments of the invention; and 
         FIG. 7  is a flowchart of a exemplary method of coupling a payload to a launch vehicle. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     1. Overview 
     Embodiments of the invention can increase the overall feasibility of various missile systems by maximizing payload configurability and eliminating additional costs associated with developing numerous unique payload bulkheads. Further, embodiments of the invention can operate as a universal adapter capable of accepting multiple alternate payloads. Embodiments of the invention describe a standardized bulkhead structure suitable for supporting any desired payload affixed to a matching payload platform. The modularized structural design accommodates ready adjustability for load and size of a given payload. In addition, a combination of payload platforms may be employed supporting a plurality of different payloads. 
     In one notable embodiment, a bulkhead panel may be constructed as a honeycomb frame which is highly configurable. The panel may be stacked to support increased payload mass. In addition, open keyways through the panel permit cable access to and from payload platforms. The panel may be constructed from a carbon composite to provide high strength at a reduced weight. 
     In one example applicable system, the Prompt Global Strike (PGS) missile may be envisioned for the employment of a common booster rocket to deliver a wide range of potential weapons payloads, depending on the target type. The number of potential weapons or payloads is large and virtually unlimited. A common payload adapter would be useful to accommodate various payload permutations. All this can be accomplished while under a reduced development schedule and cost. 
     It should be noted that embodiments of the invention may be described herein as a payload adapter for a missile system. However, embodiments of the invention are not limited to such applications and may be applied to any aerospace launch vehicle which may be used with a range of payloads. For example, embodiments of the invention may be applicable to any rocket propelled device such as a launch vehicles for satellites or other space missions. 
     2. Bulkhead and Payload Panel Structures 
       FIG. 1  illustrates a launch vehicle  100  and interface  102  to a payload  110 . The launch vehicle  100  may be a rocket for launching spacecraft or a missile for delivering weapon or any other rocket propelled device. The basic configuration of the launch vehicle  100  comprises a rocket body  106  which includes one or more engines  108  as well as fuel and possibly flight control as well as other systems to support operation. In addition, the rocket body  106  may include a single engine stage or may utilize one or more additional engine stages which separate and ignited in sequence. With any launch vehicle  100  configuration, however, a payload interface  102  is employed to structurally tie the payload  110  to the rocket body  106 . The payload  110  is positioned at the head of the launch vehicle  100  under a fairing  112  which will typically break away when the payload is finally delivered. 
       FIGS. 2A &amp; 2B  illustrate an exemplary bulkhead panel  200  for an embodiment of the invention. The bulkhead panel  200  may be configured as a honeycomb panel structure comprising interconnected hexagonal cells. The honeycomb panel structure comprises a grid of hexagonal cells, each formed from six segments  210  to close an open keyway  208  through the bulkhead panel  200  and each segment  210  is shared with adjacent cells. The bulkhead panel  200  may be secured to a launch vehicle  202  at its periphery  206  with appropriate brackets. If required by the load, additional cross members (not shown) may be used across the open end of the launch to further support the bulkhead panel  200 . However, in some embodiments structural reinforcement of the bulkhead panel  200  may be accomplished by simply stacking one or more additional bulkhead panels  204  under the first bulkhead panel  200 . It should be noted that embodiments of the invention may also employ bulkhead panels having alternate structures as long as some pattern of keyways is provided in the bulkhead panel  200  which will be used to engage payload platforms described hereafter. 
     The bulkhead panel  200  may be constructed from a composite material, such as a carbon fiber, Kevlar, aluminum (such as aluminum honeycomb panels) or any other known materials suitable for aerospace structures. For example, one structural material often used in aerospace comprises a fine honeycomb core (of very small thin walled interconnected aluminum hexagonal cells) sandwiched between aluminum or composite facesheets. Materials such as this may be cut to form the larger bulkhead panel  200  which may be further reinforced as necessary. Specific embodiments can be readily developed by those skilled in the art applying conventional aerospace structural design principles and techniques. 
       FIGS. 3A &amp; 3B  illustrate an exemplary payload platform  300  for coupling to a bulkhead panel  200 . The payload platform  300  comprises a payload panel  302  that is used to directly support a given payload, e.g. weapon, satellite, etc., affixed to its top surface in use. In addition, a pattern  304  of keys  308  on the lower surface of the payload panel  302  which are matched to engage an available pattern of keyways on the bulkhead panel  200 . In the example, each key  308  is hexagonal and sized to engage a matching hexagonal cell in the bulkhead panel  200 . In addition, the payload panel  302  of the payload platform  300  also includes through holes  310  or some other feature which are used to structurally secure the payload platform  300  to the bulkhead panel  200 , e.g. with threaded bolts or other fasteners. The payload platforms  300  may be constructed of the same range of materials that are applicable to the construction of the bulkhead panel  200  described above. Configurability of the interface to accommodate different payload applications is discussed in the next section. 
     3. Configurable Keyways and Keys Coupling Payload and Bulkhead Panels 
       FIG. 4  illustrates keyways and keys used to couple payload platforms to a bulkhead panel in an exemplary payload adapter system  400 . One important advantage afforded embodiments of the invention is the ability to be readily configured to support different payloads  402 A- 402 C. For example, a weapon payload  402 A, a telemetry control payload  402 B and a satellite payload  402 C are a few examples of payload types that may be used with embodiments of the invention. This versatility is facilitated through the distinct keyway patterns  404 A- 404 C that can accommodate the matching key patterns  406 A- 406 C of the payload platforms  408 A- 408 C by the bulkhead panel  410 . The various payloads  402 A- 402 C may be coupled to the bulkhead panel  410  alone or in combination depending upon the particular mission design. 
     It should be noted that the repeating hexagonal grid (or any similar repeating pattern) of the bulkhead panel  410  affords enhanced versatility to accommodate a large number of payload platforms in different locations and orientations. This is due in part because the bulkhead panel  410  incorporates a repeating pattern with six-fold symmetry. Thus, the key pattern  406 C for the satellite payload platform  408 C may be relocated into any available location on the bulkhead panel  410  and may be reoriented in sixty degree increments. (The individual keyways of the keyway patterns  404 A- 404 C are only marked in black in  FIG. 4  for illustration purposes; there is no structural difference in keyways of the patterns from all the other keyways of the grid.) It will be understood by those skilled in the art that other bulkhead panel designs with other keyway patterns may be developed within the scope of the invention. For example, other repeating symmetric patterns may be readily developed to accommodate coupling bulkhead panels and payload platforms. 
       FIGS. 5A &amp; 5B  illustrate an exemplary bulkhead panel structure and mechanical interface. The bulkhead panel  500  may comprise a frame or grid comprised of repeating hexagonal keyways  502  which also may provide structural support of the coupled payload platforms, e.g. carrying shear loads between the panels. As previously described, the keyways  502  may also be used as convenient cable pathways for routing support cables (electrical or other) between the payloads and the launch vehicle. Structural inserts  504  may be embedded in the grid at various locations to secure the one or more payload platforms  506  to the bulkhead panel  500 . 
     As shown in  FIG. 5B , the structural inserts  504  may be threaded inserts, each for receiving a bolt  508  for securing the one or more payload platforms  506 . Each of the structural inserts  504  may be disposed in each segment of the hexagonal grid of the bulkhead panel  500  in the example. 
     4. Exemplary Mission Applications of a Universal Adapter 
     Embodiments of the invention can be used to support a variety of different missions which may include one or more payload types coupled to the bulkhead panel. For example, the one or more payload panels may be used to support one or more satellites or the one or more payload panels may be used to support one or more payload support systems and one or more payloads. Payload support systems may include telemetry (TLM) modules or global positioning system (GPS) used to operate the particular payload. 
       FIGS. 6A to 6C  illustrate some exemplary weapon payload platform configurations for embodiments of the invention.  FIG. 6A  illustrates a basic configuration of a weapon payload  600 A and an applicable keyway pattern  602 A for mounting a payload platform supporting the weapon payload  600 A. The pattern  602 A is centrally disposed on the bulkhead panel  608 A.  FIG. 6B  illustrates a configuration supporting a pair of weapon payloads  600 B which are coupled to the bulkhead panel  608 B at two separate keyway patterns  602 B.  FIG. 6C  illustrates another configuration of three weapon payloads  600 C which are now coupled to the bulkhead panel  608 C by three separate patterns  602 C. In addition, secondary payloads  604 C (e.g., telemetry and GPS) may also be coupled to the bulkhead panel  608 C by separate patterns  606 C. 
       FIG. 6D  illustrates an exemplary communications satellite payload platform configuration embodiment of the invention. In this embodiment the bulkhead panel  608 D has a keyway pattern  602 D to receive the satellite payload  600 D fixed to the matching payload platform. In addition, a second payload  604 D telemetry unit is located on the bulkhead panel  608 D at a single keyway pattern  606 D. 
       FIG. 6E  illustrates another weapon payload configuration embodiment of the invention. In this case the single weapon payload  600 E is quite large and requires an expansive pattern  602 E on the bulkhead panel  608 E. In addition, a seconday payload  604 E telemetry unit is also located on the bulkhead panel  608 E at a single keyway pattern  606 E. 
     These and other payload configurations may be readily developed by those skilled in the art. The payload platform layout may be quickly designed and moved immediately to analysis and testing. It is also possible that a relatively minor amount of custom structural reinforcement may be applied to close a particular mission design as necessary. 
     Currently, various launch vehicles including space rockets and intercontinental ballistic missiles (ICBMs) as well as short range missiles require unique bulkheads or adapters that must be developed and employed for each payload. Specific detailed applications for various launch vehicles, e.g., Minotaur, Delta, Atlas, Arianne, can be readily developed according to the description provided here as will be understood by those skilled in the art. 
     5. Method of Coupling a Payload to a Launch Vehicle 
       FIG. 7  is a flowchart of a exemplary method  700  of coupling a payload to a launch vehicle. The method  700  of coupling a payload to a launch vehicle begins with the operation  702  of securing a bulkhead panel to a launch vehicle, the bulkhead panel having a keyway pattern of structural keyways. Next, in operation  704  matching structural keys are received into one or more of the structural keyways, the matching structural keys being attached to one or more payload platforms. Finally, in operation  706 , the one or more payload platforms are secured to the bulkhead panel by an insert pattern of structural inserts in the bulkhead panel. The method  700  may be further modified consistent with apparatus and system embodiments previously described. 
     This concludes the description including the preferred embodiments of the invention. The foregoing description been presented for the purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise forms disclosed. Many modifications and variations are possible within the scope of the foregoing teachings. Additional variations of embodiments of the invention may be devised without departing from the inventive concept as set forth in the following claims.