Abstract:
An aerial vehicle launcher including a rail having a first end and a longitudinal axis and a piston movable in a passageway formed in the rail, the piston connected to a carriage by at least two elongate flexible members. The carriage having a support device for releasably engaging the aerial vehicle. Upon the carriage and the aerial vehicle approaching one end of the rail, the support device controllably disengaging the aerial vehicle, permitting the aerial vehicle to be launched. A device is connected to a pressurized gas source, the device controllably providing pressurized gas from the pressurized gas source to the passageway for drivingly moving the piston, the carriage, and aerial vehicle along the rail for launching the aerial vehicle. The device includes a reservoir for holding pressurized gas, the reservoir being a conduit, the pressurized gas in the reservoir providing the driving force for launching the aerial vehicle.

Description:
FIELD OF THE INVENTION 
       [0001]    The present invention is directed to the field of aerial vehicle launchers, and in particular, for portable aerial vehicle launchers. 
       BACKGROUND OF THE INVENTION 
       [0002]    Aerial vehicles, such as unmanned aerial vehicles, may require a launcher or launching system. Such launchers typically utilize a series of high load springs to achieve the high acceleration required to reach required flight speed of the aerial vehicle in a short distance. Due to the tension requirements of these springs being immense as well as the launch event being so violent, the springs are subject to failure, requiring disruptive, frequent and often expensive routine maintenance. Additionally, these spring systems are typically heavy, requiring several operators and a utility vehicle to transport the launcher. 
         [0003]    It would be desirable to have a launcher that does not suffer from these deficiencies, the launcher being portable, dependable, and easily and quickly assembled and disassembled. 
       SUMMARY OF THE INVENTION 
       [0004]    In an embodiment, an aerial vehicle launcher includes a rail having a first end and a longitudinal axis. The launcher further provides a piston movable in a passageway formed in the rail, the piston connected to a carriage by at least two elongate flexible members. The aerial vehicle launcher further provides the carriage having a support device for releasably engaging the aerial vehicle. The aerial vehicle launcher further provides upon the carriage and the aerial vehicle approaching one end of the rail, the support device controllably disengaging the aerial vehicle, permitting the aerial vehicle to be launched from the launcher. The aerial vehicle launcher provides a device connected to a pressurized gas source, the device controllably providing pressurized gas from the pressurized gas source to the passageway for drivingly moving the piston, the carriage, and aerial vehicle along the rail for launching the aerial vehicle. The device includes a reservoir for holding gas pressurized to a predetermined level, the reservoir being a conduit, the pressurized gas in the reservoir providing the driving force for launching the aerial vehicle. 
         [0005]    In another embodiment, a method for launching an aerial vehicle includes slidably securing a carriage to a rail having a longitudinal axis and positioning the rail at a predetermined acute angle relative to a horizontal plane. The method further includes releasably engaging the aerial vehicle to the carriage and controllably providing pressurized gas for drivingly moving the carriage and aerial vehicle along the longitudinal axis for launching the aerial vehicle. The method further includes controllably disengaging the aerial vehicle from the carriage in response to the carriage and the aerial vehicle being a predetermined spacing from an end of the rail immediately prior to launch of the aerial vehicle. 
         [0006]    Other features and advantages of the present invention will be apparent from the following more detailed description, taken in conjunction with the accompanying drawings which illustrate, by way of example, the principles of the invention. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0007]      FIG. 1  is an upper perspective view of an exemplary embodiment of a launcher. 
           [0008]      FIG. 2  is an enlarged upper perspective view of a rail from the launcher of  FIG. 1 . 
           [0009]      FIG. 3  is a cross-section taken along line  3 - 3  from  FIG. 2 . 
           [0010]      FIG. 4  is a cross-section taken along line  4 - 4  from  FIG. 2   
           [0011]      FIG. 5  is an upper perspective view of disassembled mating portions of a rail. 
           [0012]      FIG. 6  is an upper perspective view of mating portions of the rail of  FIG. 5  assembled together. 
           [0013]      FIG. 7  is an enlarged partial elevation view of the front end of the rail of  FIG. 2 . 
           [0014]      FIG. 8  is an enlarged partial upper perspective view of the rear end of the rail of  FIG. 2 . 
           [0015]      FIG. 9  is an upper perspective view of an exemplary carriage. 
           [0016]      FIG. 9A  is an upper perspective view of an exemplary unmanned aerial vehicle supported by the carriage of  FIG. 9 . 
           [0017]      FIG. 10  is an upper perspective view of an exemplary embodiment of a pneumatic control system. 
           [0018]      FIG. 11  is a plan view of the pneumatic control system of  FIG. 10 . 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0019]    As shown in  FIGS. 1-9, 9A, and 10-11 , the present disclosure provides a portable pneumatic aerial vehicle launcher or launching system  10  ( FIG. 1 ), such as unmanned aerial vehicles (UAVs)  12  having an open platform which allows UAVs of varying shape and size to be launched from rest to flight speed in a short distance. The launcher  10  includes three major subcomponents; a rail  14 , a carriage  16 , and a device or pneumatic assembly  18 . The carriage  16  features the components necessary to properly hold the UAV  12  during acceleration, and completely release the UAV at the end of the rail  14 . The rail  14  includes a guiding track for the carriage  16 , and features an enclosed pneumatic piston system which with the assistance of two elongate flexible members such as guiding ropes or cables  103  and pulleys  102  provides a 1:1 ratio of movement between a piston  101  and carriage  16  on the rail  14 . In one embodiment, the ratio of movement between guiding ropes or cables  103  and pulleys  102  can be different than 1:1 to achieve a mechanical advantage. For improved portability, the rail  14  is made of sections or portions  124  which are removable without the need for tools, allowing for portability and the ability of a single operator to assemble and disassemble. Other components, such as guiding ropes or cables  103  can be selectably assembled and disassembled from the carriage  16  without the need for tools. Additionally, the rail  14  features two front legs  108  and a rear leg bar which are adjustable in both angle and length, allowing usage in all sorts of terrain. In one embodiment a different number of legs may be utilized. To power the pneumatic piston, the pneumatic assembly features a system allowing for the storage, regulation, and release of pressurized gas. Within this pneumatic system, a launch valve, high pressure “storage” reservoir, low pressure “launch” reservoir, and a series of pneumatic controls facilitates distributing a specific volume of gas at a user-controlled pressure to the pneumatic piston, enabling the launch event. 
         [0020]    The term “UAV” or “launch vehicle” and the like may be used interchangeably. 
         [0021]    The term “rail  14 ” and “rail subassembly  100 ” and the like may be used interchangeably. 
         [0022]    The term “without tools,” “without the need for tools” and the like is believed to be self explanatory, at the least, the magnitude of forces and level of manual dexterity associated with successfully achieving assembly and dissassembly associated with a given task would be possessed by any operator that would otherwise be able to use tools in order to achieve the same task. 
         [0023]    The launcher of the present disclosure provides a safer and more sustainable alternative to traditional UAV launching devices using a series of high load springs. Additionally, the launcher of the present disclosure provides a safer and more useable alternative to a traditional pneumatic UAV launching device. 
         [0024]    Rail  14  comprises a rail subassembly  100  which includes rail sections or portions  124 , front and rear end caps  126 ,  128 , cable  103 , legs  108 , and pneumatic piston  101 , as shown in  FIGS. 2-8 . During the launch event, pressurized gas enters the inlet  109  ( FIG. 7 ) of the rail  14  from launch reservoir  316  ( FIG. 1 ), which drives the piston  101  ( FIG. 3 ) from the front of the rail subassembly  100  to the back of the rail subassembly. At the rear of the rail subassembly  100 , an outlet filter, such as a wire mesh filter  117  ( FIG. 4 ) in fluid communication with the passageway  130  ( FIG. 3 ) prevents external debris from entering the passageway and reaching the piston  101 , evenly distributes the pressurized gas flow and dampens the noise of the pressurized gas displaced by the piston  101 . The piston  101  is attached to two cables  103 , which are attached at the front and back of the carriage assembly  200 . To minimize the need for cleaning and lubrication, the piston&#39;s  101  seals utilize a dry sealing method by being constructed of a low-friction polymer. By using a low-friction polymer in lieu of a traditional seal made of an elastomer, no lubricants are needed, therefore making the piston self-cleaning and resistant to usage in extreme environments. Additionally, in one embodiment, the two cables  103  are made of a coated polyamide fiber braid, which resists moisture absorption common in fiber ropes, is less prone to stretch-related fatigue as is common in other rope materials, and upon failure doesn&#39;t whip violently as is the case with metallic wire rope. When the piston  101  moves towards the rear of the rail subassembly  100 , the pulley  102  guides the cable  103  outside and above the rail subassembly  100 , pulling the carriage assembly  200  from the rear to the front of the rail subassembly  100 . Prior to reaching the end of the rail subassembly  100 , the piston  101  strikes an impact spring  118  ( FIG. 4 ), which quickly but safely brings the carriage assembly  200  to a stop. 
         [0025]    As shown in  FIGS. 5 and 6 , the rail subassembly  100  can include, but is not limited to, four separate sections or portions  124 , which are attached to each other using latches  104 , such as over-center latches. These latches compress the ends of each section together, creating a fluid tight seal. To achieve a fluid tight seal, a male- and female-coupler  111  featuring a gasket  112  are used, with anti-rotation features such as alignment pins  113  and corresponding openings to receive the pins to prevent rotation of facing ends of adjacent rail sections or portions once the male and female portions of the coupler are assembled together. To prevent the carriage assembly  200  from rotating during the launch event, an anti-rotation feature such as a carriage guide rail  105  is positioned on both the top and bottom of the rail subassembly  100 , which slidably engages corresponding slots formed in guide blocks  204  (only one guide block  204  is shown in  FIG. 9 ) of the carriage assembly, providing a straight track for the carriage assembly  200  ( FIG. 9 ) to follow. In one embodiment, at the front end of the rail subassembly  100 , a raised section of the carriage guide rail  105  triggers the engagement portion  209  ( FIG. 9 ) to release its arms  214 , allowing the arms to move free of the UAV  12  ( FIG. 9A ) when the piston  101  strikes the impact spring inside the rail. 
         [0026]    In one embodiment, the outer structural rail tubes  115  ( FIG. 5 ) are made of epoxied composite (carbon) fiber to minimize the weight of the rail subassembly  100  while retaining tensile and compressive strength. To counteract the weakness of carbon fiber tubes under tensile loading by its ends; all couplers  111 , and carriage guide rails  105  are designed to eliminate point loads, maximizing load distribution across the entire tube. This design consideration improves the overall strength of the rail subassembly  100  when using other materials for the outer structural rail tubes  115 , as the maximized load distribution reduces the risk of fracture or yield regardless of the material. Additionally, in one embodiment, the frontmost section of the rail subassembly  100  is filled with a structural filler to prevent shear loads on the structural rail tube  115  as a result of the carriage assembly  200  decelerating at the end of the rail subassembly and its interfacing components bearing down on the tube&#39;s walls. 
         [0027]    To support the rail  14 , two front legs  108 , and rear leg bar  119  suspend the rail off the ground, and are adjustable to provide the optimal launch angle. Other leg arrangements can be used to support the rail. To achieve both angular and height adjustability, the front legs  108  feature telescoping tube clamps, allowing sufficient height adjustment to achieve any desired incline, as well as angular adjustment hinges  107  ( FIG. 7 ) to position/balance itself on an incline/decline. Additionally, the angular adjustment hinges  107  feature shear pins to prevent damage to the leg and rail interface in the event the leg became snagged during a launch. When in storage/transport, the hinges  107  can be adjusted to allow the legs  108  to be parallel to the rail, providing a compact package that permits handling by a single operator. Additionally, the legs  108  and leg bar  119  feature pivoting removable and interchangeable shoes, sometimes referred to as feet, with a soft rubber option for hard surfaces (e.g., concrete, asphalt), as well spiked cleats for soft terrain (e.g., sand, dirt, snow). To prevent the front legs  108  from separating from one another, a wire rope  116  with crimped loops are permanently affixed to a mounting point on each leg. 
         [0028]    Present on the rear leg bar  119  ( FIG. 8 ) are adjustable threaded rods  120 , allowing for fine height adjustment; as well as pins  121  to completely remove the leg bar from the rail during storage/transport. Attached to the leg bar  119  is a backing rod  122 , which may be used to back the rail  14  against a tree, wall, or other stationary surface. The backing rod  122  also features a bumper on its distal end, which helps to dissipate the energy stored in the rod  122  during the launch event. When used in soft terrain, ropes can be attached to the rail  14  using mounting loops and are attached to stakes to prevent longitudinal movement. For precise adjustment, an inclinometer  110  ( FIG. 7 ) is attached to the front end cap  126 , providing precise angle display relative to a horizontal plane, as well as a level indicator  106  to ensure the rail  14  is level, i.e., corresponding to a predetermined reference angle (roll) relative to longitudinal axis  180  ( FIG. 2 ) of the rail. 
         [0029]    As shown in  FIG. 9 , carriage  16  includes a carriage assembly  200 . In one embodiment, all structural components of carriage assembly  200  can be composed of sheet metal, but may be manufactured using advanced manufacturing methods and materials which allows for a reduction in weight while not compromising strength. 
         [0030]    As further shown in  FIG. 9 , carriage  16  comprises a support member  20  including an engagement portion  201  for releasably engaging the UAV or aerial vehicle  12  ( FIG. 1 ). In one embodiment, such as shown in  FIG. 9 , engagement portion  201  includes a guide channel  208  for engaging the UAV ( FIG. 9A ) and preventing the UAV from sliding laterally relative to the carriage  16  during a launch event. In one embodiment, the guide channel is adjustable for accommodating differently sized UAVs. In one embodiment, the guide channel  208  moves out of a path of the aerial vehicle, such as by mechanical linkages or springs (not shown) as the aerial vehicle reaches a predetermined spacing from the front end (at front end cap  126  ( FIG. 2 )) of the rail  14 , or the carriage  16  begins decelerating at the front end of the rail, preventing an impact with the UAV. In one embodiment, such as further shown in  FIG. 9 , engagement portion  201  includes one or more protrusions, such as mounting pins  212  for engaging the UAV ( FIG. 1 ) in preparation of a launch event. It is appreciated by those having ordinary skill in the art that other features may be incorporated in engagement portion  201 , which features to be compatible with corresponding features of the UAV in order to engage and secure the UAV in preparation for and during a launch event. Upon reaching the end of the rail  14  ( FIG. 1 ) (and decelerating) during a launch event, the UAV ( FIG. 1 ) will leave the carriage  16  ( FIG. 1 ) and begin flight. The carriage assembly  200  is attached to a pneumatic piston  101  ( FIG. 3 ) located within a passageway  130  ( FIG. 3 ) formed in the rail using two elongate members such as ropes or cables  103  ( FIG. 3 ) which are affixed to the carriage assembly at predetermined positions, such as by using fastening devices such as clevis anchors  203  on both the front and rear of the carriage assembly. The passageway  130  provides directional control of pressurized gas from a pressurized gas source  303  ( FIG. 10 ) for driving the piston  101 . 
         [0031]    In one embodiment, as further shown in the rear of the engagement portion  201  of carriage assembly  200  in  FIG. 9 , a rear support arm  207  prevents the UAV ( FIG. 9A ) from slipping past the carriage  16  when the launch event commences. Slipping prevention is achieved by the two pads  202  and a knuckle  206 . Knuckle  206  constrains the pads to move in a direction toward or away from each other. In one embodiment, each pad has a corresponding knuckle. The freedom of movement provided by the knuckle&#39;s universal ball joint permits locking the tail of the UAV ( FIG. 9A ) in place with the pads  202 . In one embodiment, this construction provides a universal mounting geometry that is able to affix to differently sized and shaped aerial vehicles. In one embodiment, this construction prevents roll and yaw of the aerial vehicle, as well as lift separation of the aerial vehicle from the launcher prior to controllable disengagement therefrom. In one embodiment, pads  202  may include protrusions  212 . Upon decelerating at the release point on the rail&#39;s end, the arm  207  rotates at least partially in a direction of movement of the UAV ( FIG. 9A ) or launch vehicle, as well as downwards relative to the carriage  16 , out of a path of the aerial vehicle as the aerial vehicle reaches a predetermined spacing from the front end (at front end cap  126  ( FIG. 2 )) of the rail  14 , or the carriage  16  begins decelerating at the front end of the rail, preventing an impact with the UAV&#39;s tail elevator. In one embodiment, carriage assembly  200  includes an engagement portion  209  having support arms  214  and pads  202  and/or protrusions  212  operating in a manner similar to that previously discussed with regard to engagement portion  201 , although in another embodiment, support arms  214  may independently rotate outwardly or perpendicular to the direction of travel of the carriage assembly. Any combination of engagement portions  201 ,  209  and guide channels  208  may be used as desired or appropriate to engage the UAV ( FIG. 9A ) for a launch event. 
         [0032]    As further shown in  FIG. 9 , to prevent the UAV ( FIG. 9A ) from rolling, the carriage assembly  200  has anti-rotation features such as guide blocks  204  that slidably engage with carriage guide rails  105  when assembled together, which cradle the guide rail on the top and bottom of the launcher&#39;s rail sections  124 . For improved portability, the tail section (if present) of the carriage assembly  200  can be detached by removing the quick release pins holding the tail section and its interface tabs  205  to the rest of the carriage assembly. 
         [0033]    As further shown collectively in  FIGS. 10 and 11 , the pneumatic assembly  18  includes an integrated launch valve  301 , a launch reservoir  316  ( FIG. 1 ), and a pneumatic control system  305  including a pneumatic control panel  314 . The launch valve  301  outlet shown in  FIG. 7  is attached to the end cap  126  inlet of the rail subassembly  100  in fluid communication with passageway  130  ( FIG. 3 ), providing a direct interface into the passageway without a need for adapters. On the launch valve  301  inlet ( FIG. 11 ), the end of the pressurized launch reservoir  316  ( FIG. 1 ) is attached. To activate the valve, a pneumatic pilot controlled by the pneumatic control panel  314  ( FIG. 11 ) is utilized, which upon receiving the “pressure signal” via a conduit ( FIG. 1 ) extending between the launch valve  301  and the pneumatic control panel  314  ( FIG. 11 ), the launch valve becomes unbalanced and is activated, forcing the launch reservoir&#39;s pressurized gas to be deployed into the piston  101 , launching the UAV. The launch valve  301  features a visual pressure indicator  114  on the launch reservoir side of the valve, indicating to the operator that the valve is pressured and ready to be actuated. Additionally, the usage of the launch reservoir  316  in the form of a conduit, such as a hose ( FIG. 1 ) allows the pneumatic control system  305  to be located away or spaced apart from the launch valve  301  of the rail subassembly  100 , mitigating any potential safety hazards if the operator were to be in close proximity to the aerial vehicle during both the launch event or termination of the launch event. 
         [0034]      FIG. 10  shows the pneumatic control system  305  including a pneumatic control panel  314 , which includes a series of controls and safeguards to safely and reliably permit a high pressure stored gas to be deployed to the launch reservoir at a user-controlled pressure. The high pressure gas is stored in the high pressure cylinder  303 , which allow for several launches to be performed per cylinder without need for recharging. It is to be understood that the number of launches is a function of the size and pressure of numerous parameters, including the size and pressure capacity of the high pressure cylinders and can be adjusted as desired, as can the launch pressure utilized to accommodate aircraft of differing weights and required takeoff speeds. The pneumatic control system case  312 , shown in  FIG. 10 , contains and protects all elements of the pneumatic control system  305  from environmental factors such as weather and transport damage. To safely secure high pressure cylinders  303 , mounting brackets  308  and clamps  302  are permanently affixed to the case. As a visual aid during assembly and usage, a removable wind vane and panel-illuminating light are affixed to the inside of the pneumatic control system case  312 . 
         [0035]    In the pneumatic control system assembly  305 , including a pneumatic control panel  314 , a series of pneumatic controls are utilized. A high pressure charge port  307  is used as the interface to charge one or more high pressure cylinders  303  (in  FIG. 10 , only one high pressure cylinder is shown) with pressurized gas. In one embodiment, the high pressure cylinders can be charged to 5000 psig. In other embodiments, the high pressure cylinders can be pressurized to other pressure magnitudes, as desired and appropriate to maximize the amount of launches without need for recharging. The pressure in the high pressure cylinders is visible to the user or operator via the pressure gauge  306 . A high pressure shutoff valve  304  protects all low-pressure components from the high pressure gas when the system isn&#39;t in use. When open, the high pressure shutoff valve  304  feeds high pressure gas to the high-to low-pressure regulator  309 . To indicate the regulated pressure, a gauge  306  displays the pressure to the user on the pneumatic control panel. In one embodiment, pneumatic control panel  314  includes an intuitive panel layout, with color-coded subsystem labeling. 
         [0036]    When the launch reservoir  316  ( FIG. 1 ) is ready to be filled, the first of a series of hand-operated switches  310  provides pressurized gas to the launch reservoir. In one embodiment, the switches  310  are a combination of locking and momentary pneumatic rocker switches. In other embodiments, they may be push buttons, pedals, or levers, as well as any configuration of the aforementioned switches but utilizing electrical actuation. In one embodiment, the launch reservoir  316  ( FIG. 1 ) is a conduit, such as a hose, allowing the pneumatic control system or pneumatic control assembly  305  to be set a distance away from the rail  14 . The pressure in the launch reservoir is indicated by a pressure gauge  306 B. When the user is ready to initiate a launch, a configuration of two-hand safety switches  310  is actuated, such as by toggling, providing pressure to the launch valve&#39;s  301  pilot port, releasing the launch reservoir&#39;s pressurized gas into the rail subassembly  100 . In the event the launch is to be aborted, and the launch reservoir is pressurized, the launch reservoir drain valve  310  can be opened to release the pressurized gas stored in the launch reservoir to atmosphere. By utilizing the pneumatic control panel  314 &#39;s series of switches, valves, and regulators, the redundant system provides safeguards to prevent damage to components and ease of operator usage. 
         [0037]    As a result of arrangement of the launcher of the present disclosure, a single operator can assemble the launcher and launch an aerial vehicle quickly, in extreme environmental conditions, and have a minimal launch recovery time. In one embodiment, the launch recovery time is less than one minute. The reusability of the launcher is dependent on the fill pressure of the high pressure cylinders  303 , as a higher high pressure fill will allow for more launches before all pressurized gas is used. When the high pressure cylinder  303  is exhausted, it can be recharged quickly and repeatedly. 
         [0038]    While the invention has been described with reference to a preferred embodiment, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the appended claims.