Patent Publication Number: US-2005127242-A1

Title: Payload dispensing system particularly suited for unmanned aerial 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 any payment of any royalty thereon or therefor. 
    
    
     BACKGROUND OF THE INVENTION  
      1.0 Field of the Invention  
      The present invention relates to dispensing systems and, more particularly, to payload dispensing systems particularly suited for use on unmanned aerial vehicles.  
      2.0 Description of the Related Art  
      Unmanned aerial vehicles, which includes drones, are pilot-less airplanes controlled from a ground station by the use of RF signals. Unmanned aerial vehicles (UAVs) have many useages, one of which may be the accurate delivery of a payload to a designated site, such as a target of interest.  
      The accuracy of the delivery of the payload is dependent upon the accuracy at which the payload is dispensed from the UAVs to the target of interest. It is desired that a payload dispensing system be provided that is particularly suited to be mounted on an unmanned aerial vehicle and that allows the payload to be accurately dispensed from the unmanned aerial vehicle.  
     OBJECTS OF THE INVENTION  
      It is a primary object of the present invention to provide a payload dispensing system that accurately dispenses the contents of its payload and that is particularly suited to be mounted on an unmanned aerial vehicle.  
      It is another object of the present invention to provide for a payload dispensing system that accepts atmospheric data so as to further improve the accuracy at which the payload dispensing system dispenses the contents of its payload.  
      Another object of the present invention is to provide a payload dispensing system and a method of operation thereof that is easily integrated into unmanned vehicles.  
     SUMMARY OF THE INVENTION  
      This invention is directed to a payload dispensing system particularly suited for being mounted on an unmanned aerial vehicle that communicates with a ground control system. The payload dispensing system comprises a receiver, a transmitter, an autopilot, and a payload dispenser. The receiver receives information from the ground station and provides corresponding output signals. The transmitter transmits information to the ground station and to the autopilot. The autopilot responds to the output signals of the receiver and provides corresponding output signals to the transmitter. The payload dispenser comprises a computer, a magazine, and a controller. The computer comprises at least one input port for receiving the output signals from the receiver and at least one output port. The magazine holds the payload comprising a plurality of tubes, each containing a capsule and each having a cartridge actuating device responsive to an electrical signal. The controller is connected to the at least one output port so as to receive information from the computer and generates corresponding output signals therefrom. The controller has electrical means for being connected to each of the cartridge actuating devices. The controller responds to the information from the computer and generates respective electrical signals to the cartridge actuating devices causing respective capsules to be ejected from the respective tube. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
      A better understanding of the present invention may be realized when considered in view of the following detailed description, taken in conjunction with the accompanying drawings.  
       FIG. 1  is a simplified drawing of an unmanned aerial vehicle that houses the payload dispensing system of the present invention.  
       FIG. 2  is a block diagram of one embodiment of the payload dispensing system of the present invention.  
       FIG. 3  illustrates one embodiment of a payload dispenser of the present invention.  
       FIG. 4  illustrates another embodiment of the payload dispenser of the present invention.  
       FIGS. 5A and 5B  illustrate a flow chart of one of the operating programs of the present invention running in a ground station.  
       FIG. 6  illustrates a magazine section that is part of the payload dispenser of the present invention.  
       FIG. 7  illustrates one tube of the payload dispenser of the present invention.  
       FIG. 8  illustrates another embodiment of the payload dispensing system of the present invention.  
       FIG. 9  illustrates a further embodiment of the payload dispensing system of the present invention.  
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
      Referring to the drawings, wherein the same reference number indicates the same element throughout, there is shown in  FIG. 1 a  payload dispensing system  10  that is mounted in a unmanned aerial vehicle  12  shown in a simplified manner. The unmanned aerial vehicle  12  comprises a magazine  14  which may be an ALE-47 type known in the art; payload avionics  16  that includes a dispenser computer, dispenser controller and dispenser data link transceiver each of which may be of a different type dependent on the preferred embodiments to be described; and a transceiver antenna  18 .  
      In general, the unmanned aerial vehicle  12  conveys the payload dispensing system  10  to a designated site, such as a target of interest, wherein the payload of the payload dispensing system is released upon command from a ground control station so that the contents of the payload fall from the unmanned aerial vehicle  12  under the influence of gravity. The payload dispensing system  10  provides for the accurate release of the contents of the payload from the unmanned aerial vehicle  12  all of which may be further described with reference to  FIG. 2 .  
      The unmanned aerial vehicle  12 , which carries the payload dispensing system  10  is controlled by a ground station  24  having transmitting and receiving elements  24 A and  24 B respectively. In some embodiments, the unmanned aerial vehicle  12  is also controlled from inputs from a forward spotter  26  that routes the related information to the ground control station  24 . The ground control station  24  may also receive, via the signal path  24 C, information from an associated external transmitter  28 .  
      The payload dispensing system  10  comprises a receiver  30 , having a receiving element  32  (provided by the transceiver antenna  18  in  FIG. 1 ), that receives a RF signal from the ground control station  24  by way of RF link  34 . The payload dispensing system  10  further comprises a transmitter  36  that transmits information, via its transmitting element  38  (provided by the transceiver antenna  18  in  FIG. 1 ), to the ground control station  24 , via element  24 B and RF link  40 . The payload dispensing system  10  still further comprises an autopilot  42  which receives information from the receiver  30 , by way of signal path  44 A, and transmits corresponding output signals to transmitter  36 , by way of signal path  44 B.  
      The payload dispensing system  10  preferably further comprises first and second video cameras  46  and  48  that respectively provides their output signals, via signal paths  50  and  52 , to a video switcher  54 . The video switcher  54  transmits information on signal path  56  to transmitter  36  and receives information on signal path  58  from receiver  30 .  
      The first camera  46  is preferably mounted on the front end of the unmanned aerial vehicle  12  and serves as a forward video camera, whereas the second video camera  48  is preferably mounted on the unmanned aerial vehicle  12  so as to view downward therefrom and serves as a down-look video camera. The second video camera  48  is used by a system operator utilizing the ground control station  24 , as a visual cue for determining when to release the payload contained in a payload dispensing system  10 . The video switcher  54  allows the system operator to switch between the forward camera  46 , the down-look video camera  48 , or a picture-in-a-picture view of both cameras  46  and  48 . The payload dispensing system  10  further comprises a payload dispenser  60  that receives information, via signal path  62 , from the receiver  30  and may be further described with reference to  FIG. 3 .  
       FIG. 3  illustrates the payload dispenser  60  as comprising a computer  64 , a controller  66 , and a magazine  68 . The computer  64  may be a PC104 computer which is known in the art and comprises modular computer components based on Intel processors. The computer  64  has a plurality of input ports, one of which receives output signals from the receiver  30 , via signal path  62 . The computer  64  further comprises a plurality of output ports one of which is routed to controller  66 , via signal path  70 .  
      The controller  66  receives information from the computer  64  and generates corresponding output signals therefrom.  
      The logic controller  66 , in response to the information on signal path  70 , operates to send firing pulses to the magazine  68  by way of signal path  72 . A further embodiment of a payload dispensing system  60 A may be further described with reference to  FIG. 4 .  
      The payload dispensing system  60 A, in addition to elements of the payload dispensing system  60  of  FIG. 3 , further comprises the differential GPS (DGPS) receiver  74  having an element  74 A which is part of the transceiver antenna  18  (shown in  FIG. 1 ) that receives information from an external source by way of RF link  76 . The payload dispensing system  60 A further comprises a first data link  78  that receives, via an element  78 A of the transceiver antenna  18  (shown in  FIG. 1 ), atmospheric data  80  derived from a sensor  82 . The data link  78  routes its output signals to the computer  64  by way of signal path  84 .  
      The payload dispensing system  60 A further preferably comprises a data link  86  that receives information from the receiver  30  by way of signal path  62  and routes the received information to the computer  64  by way of bilateral data path  88 .  
      The DGPS receiver  74  is made available by Omni Star and provides precise air vehicle latitude, longitude, altitude, and velocity information to the computer. The computer  64  provides on-board processing to control the DGPS receiver  74 . The data link  78  receives atmospheric data that is provided by sensor  82  which is commonly referred to as a T-drop dispenser and which is routed to computer  64 . The T-drop data is also routed back to the ground station  24 , by way of computer  64 , data link  86 , receiver  30 , and transmitter  36 . The ground station  24  utilizes the T-drop data to compute atmospheric conditions, including wind speed and direction from the drop altitude of the unmanned aerial vehicle  12  to the ground.  
      The data link  86  serves as an interface for the computer  64  to communicate to the ground station  24  and allows the ground station  24  to enter target coordinates, and the payload ballistic trajectory model to predict down-range and cross-range travel for the payload contents. The operation of the ground station  24  in response to the entered target coordinates and payload ballistic trajectory model, may be further described with reference to  FIG. 5 .  
       FIGS. 5A and 5B  illustrate a flow chart  90  of the overall operation of the present invention and is divided in to three columns  92 ,  94 , and  96  that respectively represent the actions by a human operator on the ground; actions by payload control circuit on the ground; and actions by dispenser computer in the unmanned aerial vehicle  12 . Each of the three columns  92 ,  94 , and  96  have events that are respectively given in Tables 1, 2 and 3.  
               TABLE 1                          92 (Actions by Human Operator on the Ground)                     Event   Description                             98   Operator issues T-Drop           Release command       100   Operator enters target           Coordinates       102   Operator updates UAV           Trajectory based on steering           Commands       104   Operator issues consent-to-           Fire command                    
     
       
         
           
               
             
               
                 TABLE 2 
               
             
            
               
                   
               
               
                   
               
               
                 94 (Actions by Payload Control Station on the Ground) 
               
            
           
           
               
               
            
               
                 Event 
                 Description 
               
               
                   
               
               
                 106 
                 Payload Control Station 
               
               
                   
                 relays T-Drop release command 
               
               
                 108 
                 Payload Control Station 
               
               
                   
                 calculates wind speed and 
               
               
                   
                 wind direction 
               
               
                 110 
                 Payload Control Station 
               
               
                   
                 predicts down-range and 
               
               
                   
                 cross-range travel for 
               
               
                   
                 payload canisters 
               
               
                 112 
                 Payload Control Station sends 
               
               
                   
                 target coordinates, and 
               
               
                   
                 predicted down-range and 
               
               
                   
                 cross-range travel to 
               
               
                   
                 Dispenser Computer 
               
               
                 114 
                 Payload Control Station 
               
               
                   
                 displays steering commands 
               
               
                   
                 and time-to-go to reach 
               
               
                   
                 payload release coordinates 
               
               
                 116 
                 Payload Control Station 
               
               
                   
                 relays consent-to-fire 
               
               
                   
                 command to Dispenser Computer 
               
               
                   
               
            
           
         
       
     
     
       
         
           
               
             
               
                 TABLE 3 
               
             
            
               
                   
               
               
                   
               
               
                 96 (Actions by Dispenser Computer on UAV) 
               
            
           
           
               
               
            
               
                 Event 
                 Description 
               
               
                   
               
               
                 118 
                 Dispenser Computer releases 
               
               
                   
                 T-Drop 
               
               
                 120 
                 Dispenser Computer relays T- 
               
               
                   
                 Drop data to Payload Control 
               
               
                   
                 Station 
               
               
                 122 
                 Dispenser Computer computes 
               
               
                   
                 payload release coordinates, 
               
               
                   
                 steering commands, and time- 
               
               
                   
                 to-go until payload release 
               
               
                 124 
                 Dispenser Computer sends 
               
               
                   
                 steering commands and time- 
               
               
                   
                 to-go to the Payload Control 
               
               
                   
                 Station 
               
               
                 126 
                 Dispenser Computer automatically 
               
               
                   
                 dispenses payload 
               
               
                   
                 when vehicle coordinates are 
               
               
                   
                 nearly equal to release 
               
               
                   
                 coordinates 
               
               
                   
               
            
           
         
       
     
      As seen in  FIGS. 5A and 5B , the operation is initiated by event  98  in which the operator issues a T-Drop release command that is routed to event  106  by way of signal path  128 . Event  106  responds to the release command and generates, via signal path  130 , a request to release for the T-Drop to the unmanned aerial vehicle  12  in particular, event  118  which, in turn, sends a signal, via signal path  132 , to the event  120 , which, in turn, responds, via signal path  134 , back to the payload control station, in particular, event  108  thereof, by way of signal path  134 . Event  108  supplies a signal, via signal path  136 , to the payload control station designated by event  110 .  
      Event  110  also receives, by way of signal path  138 , the operator entrance of target coordinates as indicated by event  100 . The event  110  responds to the inputs from events  108  and  100  and sends a command, via signal path  140 , to event  112  which, in turn, sends a command, via signal path  142  to event  122 . The event  122  provides information, to event  124 , via signal path  144  and event  124  supplies information, via signal path  146  to event  114 .  
      Event  114  display information to the operator as indicated in the functions shown therein. Event  114  conveys that information to event  102 , by way of signal path  148 . As shown in event  102 , the operator updates the unmanned aerial vehicle  12  trajectory based on steering commands and supplies the updated information to event  104 , by way of signal path  150 .  
      Event  104  issues the consent-to-fire command, via signal path  152  to event  116 .  
      Event  116  relays the consent-to-fire command to the dispenser computer, via signal path  154 . The dispenser computer, as indicated by event  126 , automatically dispenses a payload when the vehicle coordinates are nearly equal to the release coordinates.  
      With regard to  FIG. 4 , the computer  64  calculates steering commands and time-to-go, in a manner known in the art, until the payload release using the information from the on-board differential GPS receiver  74  and sends this data to the ground station  24 . The ground station  24 , via computer  64 , provides a consent-to-fire command when ready and the computer  64 , via the controller  66  causes the payload to be dispensed when the on unmanned aerial vehicle  12  reaches the predetermined release coordinates. The controller  66  provides the command signals to a magazine  68 , shown in  FIGS. 3 and 4 , and which may be further described with reference to  FIGS. 6 and 7 .  
      The magazine  68  comprises a rack  156  in which is logged a plurality of tubes  158   1  . . .  158   N  as shown in  FIG. 6 .  FIG. 6  also illustrates two of the tubes  158   1  . . .  158   N  as being removed, so as to expose the housing of a cartridge actuating device  160 . Each of the tubes  158   1  . . .  158   N  has a cartridge actuating device  160 . Each of the cartridge actuating devices  160  is responsive to a respective electrical signal which causes the capsules contained in the tubes  158   1  . . .  158   N  to be ejected from the respective tube  158   1  . . .  158   N . The interconnection between the cartridge actuating devices  160  and the controller  66  is provided by a breech plate  162  having an appropriate wiring harness  164  comprised of multiple paths  166   1 ,  166   2 , . . .  166   N .  FIG. 6  does not illustrate the capsules that are lodged within the tubes  158   1  . . .  158   N , but are shown  FIG. 7 .  
       FIG. 7  illustrates a capsule  168  comprised of cylinder  170  having opposite ends, with a cartridge actuating device  160  at one end and a releasable cap  172 , preferably comprised of plastic at the other end. The capsules  168  are placed in the tubes  158   1  . . .  158   N , in the magazine section  68 . The magazine section  68  is preferably mounted in the unmanned aerial vehicle  12  so that the tubes  158   1  . . .  158   N  are exposed and so that the capsules  168  are ejected from the unmanned aerial vehicle  12  when the controller  66  delivers the electrical signals to the respective cartridge actuating device  160 .  
      It should now be appreciated that the practice of the present invention provides for a payload dispensing system  10  that releases the contents of the payload in response to commands initiated from a ground control system that are accurately delivered to the controller  66  by the computer  64 .  
      A further embodiment of the present invention may be further described with reference to  FIG. 8 . The embodiment of the  FIG. 8  illustrates the utilization of wind data  174  that is routed to a ballistic trajectory model  176  (similar to that described with reference to  FIG. 5 ), via signal path  178 , whereas operating parameters of the ballistic trajectory model  176  are routed to the ground control station  24 , via signal path  180 . The wind data  174  and the ballistic trajectory model  176  are utilized by the operating program within the ground station  24  to develop the prediction of coordinates for dispensing the payload in order to more accurately designate a point on the ground for the delivery of the payload by the payload dispensing system  10 . The operating program includes a simple three (3)-degree of freedom model, known in the art, utilizing the ballistic trajectory model  176  to predict the coordinates at which to dispense the payload based upon atmospheric conditions, and unmanned aerial vehicle  12  velocity, heading, and altitude. The operating program within the ground control station  24  also calculates the depression angle for a video camera, such as the second video camera  48  of  FIG. 2 , which is included as part of the video reconnaissance payload  182  shown in  FIG. 8 . The calculations of the depression angle are performed in a manner known in the art. The depression angle information is routed to the video reconnaissance payload  182  by way of transmitter element of transceiver  18 , RF link  24 E, and receiver element of transceiver  18  of video data link  184 . The video data link  184  communicates with the video reconnaissance payload  182  by way of bilateral signal path  186 . The video data link  184  also communicates with the computer  64  by way of bilateral signal path  186 .  
      A further embodiment of the present invention may be further described with reference to  FIG. 9 .  FIG. 9  illustrates an embodiment  188  that includes the elements  182  and  184  of  FIG. 8 , as well as the autopilot  42  of  FIG. 2 . The embodiment  188  further includes a GPS receiver  190  that supplies location information, via signal path  192  to the autopilot  42 . The embodiment  188  further includes the data link  194  that supplies information to the autopilot  42  by way of signal path  196 . The data link  194  operatively cooperates with a receiver element of transceiver  18  that receives information from the transmitting element  24 A of the ground control system  24  by way of RF link  198 .  
      The embodiment  188  further comprises the utilization of payload control information which is routed to the ground control station  24  by way of signal path  202 . The ground control station  24 , in a manner similar to that described with reference to  FIG. 8 , has an operating program that provides for payload ballistic trajectory model, but having a more accurate 6-degree-of-freedom payload ballistic trajectory model (known in the art) which, in turn, improves the accuracy of the payload dispensing system  10  which, in turn, allows for the payload carried by the unmanned aerial vehicle  12  to be more accurately delivered to its target of interest.  
      It should now be appreciated that the practice of the present invention provides for various embodiments each allowing for the accurate release of the contents of the payload being carried by the unmanned aerial vehicle  12 .  
      While the invention has been described with reference to the specific embodiments, this description is illustrative and is not to be construed as limited in scope of the invention. Various modifications will occur to those skilled in the art without departing from the spirit and scope of the invention as defined by the appending claims.