Patent Publication Number: US-7721669-B1

Title: Common payload rail for unmanned vehicles

Description:
STATEMENT OF GOVERNMENT INTEREST 
   The invention described herein may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor. 
   BACKGROUND OF THE INVENTION 
   This invention is for a common payload rail for securing an added payload capability to increase the versatility of unmanned vehicles (UV). More particularly, this invention secures an added payload capability externally to unmanned systems such as unmanned undersea vehicles (UUVs) and unmanned sea-surface vehicles (USVs) with minimal modifications required to the internals of the unmanned system. 
   Contemporary methods for increasing or improving the payloads for UUVs usually involve the insertion of additional payloads within the system. This procedure frequently required space that may not be available and often involved extensive and costly modifications to internal systems in the vehicle. Later developed external payloads for USVs are generally suspended by support systems and towed behind the vehicle. The added-on support and handling systems are usually unique and expensive to construct and install and can compromise the effectiveness of the host unmanned UV. 
   Thus, in accordance with this inventive concept, a need has been recognized in the state of the art for an efficient capability to directly mount a variety of external payloads to a submerged vessel or the underside of a surface vessel or on an outrigger off the side of the vessel via a rapidly and inexpensively installed common payload rail having the payloads designed for selective connection and disconnection. 
   SUMMARY OF THE INVENTION 
   The present invention provides a common payload rail to connect external payloads to a UV such as a UUV or USV. The common payload rail has a vehicle interface module having a conforming surface rigidly secured to the unmanned vehicle and feed-through conduits. A functionality module is secured to the vehicle interface module and has internal interfacing components to minimize or eliminate any modifications to the payload and vehicle. A payload interface module having feed-through conduits is secured to the functionality module and has longitudinally extending rail structure sized to engage correspondingly shaped longitudinally extending receiving means on the payload. The longitudinally extending rail structure is shaped to extend into the longitudinally extending receiving means on the payload to arrest lateral displacement between the payload interface module and the payload. At least one securing mechanism on the payload interface module is disposed to engage the payload to arrest longitudinal displacement between the payload interface module and the payload. The feed-through conduits extending through the payload interface module and the vehicle interface module receive select ones of electrical conductors and optical fibers for power and data transmission and other communication requirements of the payload, functionality module, and unmanned vehicle. Some of the feed-through conduits can include tubes to transfer fluids between the payload, functionality module, and unmanned vehicle. The vehicle interface module, functionality module and payload interface module have essentially protuberance-free outer surfaces provided with tapered leading and trailing edges to reduce hydrodynamic drag. The longitudinally extending rail structure has a cross-sectional L-shape and the longitudinally extending receiving means is an L-shaped channel sized to slideably receive the L-shaped longitudinally extending rail structure. Preferably, the longitudinally extending rail structure is a pair of upward-extending, sliding-rail structures extending in an inverted, oppositely-facing L-shaped cross-sectional configuration and longitudinally extending on the payload interface module. The longitudinally extending receiving means is shaped as a pair of L-shaped channels that longitudinally extend in the lower part of the bottom assembly of the payload. The L-shaped channels are slightly larger than the pair of L-shaped sliding rail structures to allow the L-shaped sliding rail structures to be inserted in and contiguously slid within the L-shaped channels. The internal components&#39; of the functionality module can include a variety of self-contained internal power source components to power its own internal components and the external payload. Computer data and signal processing components, including data storage components, to store and process the data sensed and collected by the payload can be included, and sensor components can be included to provide input data to augment the unmanned vehicle and the external payload; the computer components, including data processing and data storage components, may also be arranged to make the functionality module a payload of its own. 
   An object of the invention is to provide a common payload rail for externally securing a payload on an unmanned vehicle. 
   Another object of the invention is to provide a cost effective common payload rail for externally increasing or modifying payload capability of existing UUVs and USVs in inventory. 
   Another object of the invention is to provide a common payload rail for externally securing a payload to an unmanned vehicle and interfacing electrical, electronic, and hydraulic support functions in a rapid and inexpensive installation. 
   Another object of the invention is to provide a common payload rail for externally securing a payload to the underside or outriggers on USVs or the topsides of UUVs. 
   Another object of the invention is to provide a common payload rail for mounting payloads externally on UVs to avoid expensive, time consuming modification of the limited interior volume of the UV or displacement of other internal UV systems. 
   Another object of the invention is to provide a common payload rail for mounting payloads externally on a UV for increased design efficiency and reduced overall system acquisition costs. 
   Another object of the invention is to provide a standard interface design that permits uncomplicated and easy “slide-on/slide-off” replacement of components on a UVs rather than opening up a UV and endangering the integrity of certified vehicles/systems. 
   Another object of the invention is to provide a common payload rail for mounting payloads externally on UVs allowing a large number of future payloads to be developed and attached with ease to older generation UVs. 
   These and other objects of the invention will become more readily apparent from the ensuing specification when taken in conjunction with the appended claims. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a schematic side view of the common payload rail of the invention mounting a submerged external payload shown partially in cross-section toward the front of a UUV. 
       FIG. 2  is a schematic side view of the common payload rail of the invention mounting an external payload on the bottom of the hull of a USV. 
       FIG. 3  is an end view of the common payload rail of the invention with the bottom assembly of the payload shown partially in cross-section. 
       FIG. 4  is a side view of the common payload rail of the invention showing in cross section typical inherent attributes and functional capabilities of components contained in the functionality module. 
       FIG. 5  is a schematic side view of details of an exemplary securing mechanism for the common payload rail of the invention. 
       FIG. 6  is an end view of the common payload rail of the invention with the bottom assembly of the payload shown partially in cross-section with the upwardly extending inverted L-shaped rails of the payload rail engaging the L-shaped channels of the payload. 
   

   DESCRIPTION OF THE PREFERRED EMBODIMENT 
   Referring to  FIGS. 1 and 2 , common payload rail  10  of the invention is used to externally mount a variety of payloads  12  submerged in water  14  on an unmanned vehicle (UV)  16  such as an unmanned undersea vehicle (UUV)  18  or an unmanned surface vehicle  20 . Common payload rail  10  provides a means to secure and add payload capability externally to host vehicle UVs with minimal effort and virtually no internal modifications of the UVs and no requirements to occupy space inside the UVs. In other words, common payload rail  10  attaches externally to the surface of host vehicles such as UUV  18  or USV  20 , as well as on manned vessels and crafts, and then provides a standard mechanical, electrical, electronic, and hydraulic mating surface for external payloads  12  that are designed and built to meet the common mating interface standard of common payload rail  10 . 
   Referring also to  FIGS. 3 and 4 , common payload rail  10  is schematically depicted as having three mutually connectable modules. These modules, a vehicle interface module  22 , a functionality module  24 , and a payload interface module  26  can be tailored to meet the needs of many different payloads  12  on a wide variety of UVs. In this regard, the leading and trailing edges of modules  22 ,  24  and  26  can be tapered and the longitudinal and lateral cross-sectional configurations of modules  22 ,  24  and  26  can be appropriately hydrodynamically shaped along their longitudinal lengths to minimize hydrodynamic drag to further minimize adverse impacts on the handling and performance of UV  16 . 
   Vehicle interface module  22  can be considered as an extension of UV  16  and is preferably made from strong, corrosion resistant, or non-corrosive materials to support the static and dynamic loads of modules  24  and  26  and payload  12 . Vehicle interface module  22  has an essentially protuberance-free outer surface  23  provided with a tapered leading edge  23 A and trailing edge  23 B to reduce hydrodynamic drag of payload rail  10 . Vehicle interface module  22  has an inner conforming surface  28  shaped to accommodate and be secured to the specific UV  16  of interest. This conforming surface  28  can be attached to, or fastened onto, UV  16  via a number of different means alone or in combination. For example, these means can include epoxy and other strong adhesives adhered to and cured between conforming surface  28  and the surface of UV  16  and/or securing surface  28  to the surface of UV  16  with sealed screws, bolts, or other appropriate fasteners.  FIG. 1  shows yet another way of attaching surface  28  of vehicle interface module  22  to a torpedo-shaped UUV  18  using two tensioned metal bands  30  that are connected to vehicle interface module  22  and extend around the circumference of UUV  18 . The common payload rail  10  is thereby fastened to UUV  18  by bands  30   
   Vehicle interface module  22  has one or more feed-through conduits  32  extending through it and between UV  16  and payload rail  10  to receive select ones of electrical conductors and optical fibers for at least some of the power and data transmission and communication requirements of payload  12 , functionality module  24 , and UV  16 . Some of conduits  32  also can be used as tubes to transfer at least some of fluids such as liquid and gaseous petroleum fuel products or other gases among payload  12 , functionality module  24 , and UV  16 . 
   Functionality module  24  is securely connected to vehicle interface module  22  by any of a wide variety of well known means and is also preferably made from strong, corrosion resistant, or non-corrosive materials to support the static and dynamic loads of payload interface module  26  and payload  12 . Functionality module  24  preferably has a protuberance-free outer surface  25  having a tapered leading edge  25 A and trailing edge  25 B to create an elongate, strut-like streamlined shape for reduction of hydrodynamic drag of payload rail  10  and to reduce the effects of payload rail  10  on the dynamic handling of UV  16 . 
   Referring to  FIG. 4 , functionality module  24  can contain internal components that can help efficiently perform functions of payload rail  10  that expedite its successful operation. These internal components do not interfere with payload rail  10  as it quickly interfaces with payload  12  and the host UV  16  and require no or minimal modifications to either of them. These functional components of functionality module  24  can include, but are not limited to: self contained internal power source components  34  such as battery power, fuel cell power, or more exotic sources like flywheel inertial stored power, to provide power to both its own internal components as well as for external payload  12 ; general and custom analog and digital computer data and signal processing components  36 , including data storage components, to process payload data and its own generated data and produce effects as required; sensor components  38  that can themselves provide input data to augment the UV  16  or the external payload  12  (in effect, making common payload rail  10  a payload of its own); and effectors and actuator components  40  to produce ambient effects as needed, such as chaff or other ejections, acoustical/optical effects, drag reduction, etc. 
   Functionality module  24  can also contain buoyancy compensation components  42  that can include small reservoir tanks, miniature pumps, valves, actuators, and piping. These buoyancy compensation components  42  can be appropriately actuated to modify the impact of the assembled payload rail  10  and payload  12  on the center of gravity and buoyancy of UV  16  and, consequently, its handling and performance. Functionality module  24  can also include appropriate means for isolation  44  of the effects of vibrations throughout payload interface module  26  and vehicle interface module  22  to dampen vibrations from UV  16  to payload  12  or vice versa. This isolation can minimize impact on sensor components  38  or those sensors of UV  16  and payload  12 . The isolation means  44  can also have electrical, electro-magnetic, magnetic, and/or acoustical components to minimize impact of the effects of one system or the other, and if necessary, shield and isolate any emissions or emanations from one body to another, and/or compensate for these effects to yield an overall lower detectable radiated signal to remote sensing devices. Components  34 ,  36 ,  38 ,  40 ,  42 , and  44  can be appropriately placed in functionality module  24  by one skilled in the art to assure acceptable ballasting/center-of-gravity/buoyancy/trim and hydrodynamic handling characteristics among payload rail  10 , payload  12 , and UV  16  and to otherwise make available their intended functional capabilities. It is therefore understood that the arrangement of such components depicted in  FIG. 4  is to facilitate an understanding of this inventive concept and is not to be regarded as being limiting. 
   Signal and power connectivity is provided between and among internal components  34 ,  36 ,  38 ,  40 ,  42 ,  44 , external payload  12 , and UV  16 . This includes internal wiring and connectors embedded in both interface modules  26  and  22 . This also includes appropriate units for electrical, optical, fluidic, hydraulic, opto-electronic, and electro-magnetic communications and passing of data through feed-through conduits  46  in payload interface module  26  between external payload  12  and payload rail  10  and through feed-through conduits  32  between UV  16  and payload rail  10 . The internal wiring and connectors are fabricated, installed and interconnected using materials and procedures well established in the art. 
   Referring to  FIGS. 3 ,  4  and  5 , structural and mechanical support of payload  12  on UV  16  is provided for by payload interface module  26  that is rigidly secured to functionality module  24 . Payload interface module  26  is preferably made from strong, corrosion resistant, or non-corrosive materials to support the load of payload  12 . Payload interface module  26  also has an essentially protuberance-free outer surface  27  provided with a tapered leading edge  27 A and trailing edge  27 B to reduce hydrodynamic drag of payload rail  10 . One or more feed-through conduits extending through payload interface module  26  and between UV  16  and payload rail  10  receive select ones of electrical conductors and/or optical fibers for at least some of the power, data and/or communication needs of payload  12 , functionality module  24 , and UV  16 . Some of feed-through conduits  46  as well as feed-through conduits  32  may find use as transfer tubes for various liquids and gasses among payload  12 , functionality module  24 , and UV  16 . 
   Payload interface module  26  of payload rail  10  assures that payload  12  remains securely in place during operation and that payload  12  can be easily and quickly installed and removed. Payload interface module  26  has a pair of upward-extending, sliding-rail structures  48  made of metal or other rugged, strong material extending in an inverted, oppositely-facing L-shaped cross-sectional configuration. L-shaped sliding rail structures  48  of payload interface module  26  longitudinally extend all the way or at least a portion of the way along the length of module  26  to. L-shaped sliding rail structures  48  are disposed to be slideably received in a pair of slightly larger L-shaped channels  50  that longitudinally extend along a lower part  52  of a bottom assembly  54  of payload  12 . The slightly larger shape of L-shaped channels  50  allows L-shaped sliding rail structures  48  to be inserted into and contiguously slid within the L-shaped channels  50  of bottom assembly  54 . The locations of the L-shaped channels  50  and the rail structures  48  on module  26  and bottom assembly  54  can be reversed to produce substantially the same results. 
   Depending on their relative lengths, L-shaped channels  50  in bottom assembly  54  can contain some or all of the entire lengths of L-shaped structures  48  of payload interface module  26 . The contiguous abutting relationship between structures  48  and channels  50  laterally secure and arrest payload  12  on UV  16  via payload rail  10 . Longitudinal securing of payload  12  on UV  16  via payload rail  10  is assured by including at least one securing mechanism  56  in payload interface module  26 . Securing mechanism  56  can be quickly actuated to engage bottom assembly  54  of payload  12  to longitudinally secure payload  12  to payload rail  10  and, thus, UV  16 . 
   Referring also to  FIG. 5 , two exemplary securing mechanisms  56 , designated  56 A and  56 B, are shown although more or less than two such mechanisms can be used so long as the number chosen can securely couple payload rail  10  to payload  12 . Each securing mechanism  56 A,  56 B in payload interface module  26  has an interconnected hex-key geared sub-mechanism  58  rotated to selectively outwardly and inwardly displace an extensible pin  60  to engage recess  62  or  64 . Securing mechanism  56 A is shown having its pin  60  in the retracted position not engaging recess  62  in lower part  52  of bottom assembly  54 . Securing mechanism  56 B is shown having its pin  60  in the extended position engaging recess  64  in lower part  52  of bottom assembly  54 . The engagement of recess  64  in bottom assembly  54  of payload  12  by pin  60  of securing mechanism  56 B in payload rail  10  prevents payload  12  from longitudinally sliding relatively to UV  16 , see also  FIGS. 4 and 6 , and, simultaneously, the mechanical co-action between L-shaped sliding rail structures  48  and L-shaped channels  50  prevents virtually any lateral or yawing motions. Thus payload  12  is secured to UV  16  via common payload rail  10  of the invention. 
   The pair of longitudinally extending L-shaped rail structures  48  and mating L-shaped channels  50  could be reversed on module  26  and bottom assembly  54  of payload  12  or one of each could be used. The rail structures and mating channels could have other configurations including separated structural extensions that allow for quick engagement and release of payload  12  to payload rail  10 . These could be one or more rounded or square projections on either payload interface module  26  or payload  12  that can engage round or square shaped channels, or a series of projections engaging clamps or clasping receptacles or other engaging means. Electric or unassisted magnetic engaging components may also be used between payload interface module  26  and bottom assembly  54  of payload  12 . A feed-through conduit  55  for mating conductors, tubes and connectors is provided in bottom assembly  54  for the transfer of electromagnetic power and data as well as fluids between payload rail  10  and payload  12 . 
   The arrangement of L-shaped rail structures  48  and mating L-shaped channels  50  can have securing mechanisms  56  provided with sub-assemblies  58  that can be quickly manually actuated to pull any pins  60  that are engaging any recesses in bottom assembly  54 . This permits payload  12  to be quickly longitudinally displaced to release structures  48  from channels  50 . The current payload  12  can be quickly removed and replaced by another payload without any other mechanical complications. Quick-disconnect securing mechanisms other than those described above also can be used to secure payload  12  to payload rail  10  and will readily suggest themselves to one skilled in the art to which this invention pertains. The literature is replete with such securing means and fasteners whose design and specifications are openly published to become a standard to which bottom assemblies on different UV payloads can then be designed and constructed. 
   Common payload rail  10  of the invention can be adapted to UVs of many different types and can also be used with manned vehicles as well.  FIG. 1  shows a rapidly changeable payload  12  mounted above and on the dorsal centerline of a UUV  18  submerged in water and  FIG. 2  shows a submerged external payload  12  mounted on USV  20  below its longitudinally extending centerline. One or more of these payloads  12  could be mounted as shown and/or in an outrigger disposition by one or more payload rails  10 , provided that appropriate ballasting is provided to counterweight their effect. All of these adaptations of payload rail  10  can increase performance capabilities of the host vehicles in a way that enables current and future host vehicles to benefit from continuing technological advances, and allows them to better meet future requirements, in cost effective and timely ways. 
   Common payload rail  10  of the invention provides an uncomplicated and reliable “bridging mechanism” that allows coupling of essentially different, arbitrary payloads externally to a wide variety of host vehicles utilizing a standard coupling approach. 
   Common payload rail  10  will increase flexibility for utilizing payloads with a much broader number of varied UVs at potentially significant savings if payloads are designed and constructed to meet the open interface specification. Payload rail  10  can allow external placement of components that have been carried internally in the current generation of UVs, leaving internal spaces for other components. 
   Payload rail  10  can increase design efficiency and reduce overall system acquisition costs by providing a standard interface design using components that can be designed separately from the UV itself, and can be mated to any UV that incorporates the same interface design. This feature of payload rail  10  provides enhanced design flexibility, and allows for the interchangeability of components without having to open up or make modifications to the UV. Payload rail  10  allows a large number of future payloads to be developed and attached with ease to older generation UVs that are backfitted with the same interface design. In addition, when needed, multiple ones of payload rail  10  supporting multiple payloads  12  can be mounted on the external surfaces of UVs possibly at different orientations that may depend on geometries of the UVs. 
   Modifications and alternate embodiments of common payload rail  10  of the invention may be adapted, and differently configured to accommodate different host vehicles under different operational conditions. The disclosed components and their arrangements as disclosed herein all contribute to the novel features of this invention. Payload rail  10  of the invention is an uncomplicated and reliable application of good engineering for improving operational readiness and effectiveness of UVs and their externally mounted payloads. 
   It should be readily understood that many modifications and variations of the present invention are possible within the purview of the claimed invention. It is to be understood that within the scope of the appended claims the invention may be practiced otherwise than as specifically described.