Abstract:
A system to load and unload material from a vehicle comprises a vehicle base station and an assembly to autonomously load and unload material from the vehicle.

Description:
RELATED APPLICATIONS 
     None 
     BACKGROUND 
     The subject matter described herein relates to vehicle base stations, and more particularly to a vehicle base station that includes a platform for loading material on one or more autonomous vehicles such as an unmanned aerial vehicle (UAV) or the like. 
     Autonomous vehicles have found increased utility in industrial, law enforcement, and military applications. Examples of autonomous vehicles include drone aircraft and robotic vehicles. Some autonomous vehicles are powered, at least in part, by batteries. Thus, battery power provides a meaningful limitation on the ability to use autonomous vehicles in a persistent fashion, particularly in remote locations. Accordingly, systems and methods to enable autonomous vehicles to remove batteries or other payload and reload fresh batteries or other payload may find utility. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The detailed description is described with reference to the accompanying figures. 
         FIG. 1  is an illustration of an unmanned aerial vehicle environment in accordance with an embodiment. 
         FIG. 2  is a schematic illustration of a block diagram of an unmanned aerial vehicle base station in accordance with an embodiment. 
         FIG. 3  is a schematic illustration of a block diagram of a data processing system in accordance with an embodiment. 
         FIG. 4  is an illustration of a block diagram of a power generation system in accordance with an embodiment. 
         FIG. 5  is an illustration of a block diagram of a sensor system in accordance with an embodiment. 
         FIG. 6  is an illustration of a block diagram of a charging station in accordance with an embodiment. 
         FIG. 7  is an illustration of a block diagram of an unmanned aerial vehicle in accordance with an embodiment. 
         FIG. 8A  is an illustration of a side cross-sectional view of a vehicle base station in accordance with embodiments. 
         FIG. 8B  is an illustration of a top cross-sectional view of a vehicle base station in accordance with embodiments. 
         FIG. 9A  is a perspective view of a modular battery pack according to embodiments. 
         FIGS. 9B-9D  are illustrations of perspective views of a modular battery case and a battery receptacle in accordance with embodiments. 
         FIG. 9E  is a schematic, perspective view of a locking anchor and a locking component, according to embodiments. 
         FIG. 10  is a flowchart illustrating operations in a method to replace a payload on a vehicle, according to embodiments. 
     
    
    
     SUMMARY 
     Described herein is an exemplary system to load and unload material from a vehicle. In some embodiments the system comprises a vehicle base station and an assembly to autonomously load and unload material from the vehicle. 
     In another embodiment a method to replace a first payload on a vehicle comprises positioning the vehicle on a platform of a vehicle base station such that the first payload is aligned with an aperture in the platform, aligning an empty docking station in a payload advancing assembly with the aperture, removing the first payload from the vehicle, placing the first payload in the empty docking station of the payload advancing assembly, advancing the payload advancing assembly to align a full docking station with the aperture, and securing a second payload to the vehicle. 
     DETAILED DESCRIPTION 
     In the following description, numerous specific details are set forth to provide a thorough understanding of various embodiments. However, it will be understood by those skilled in the art that the various embodiments may be practiced without the specific details. In other instances, well-known methods, procedures, components, and elements have not been illustrated or described in detail so as not to obscure the particular embodiments. 
     One embodiment of a vehicle loading platform will be described with reference to an unmanned aerial vehicle (UAV) environment. An unmanned aerial vehicle (UAV) is an aircraft that is capable of flying without human operators being present in the aircraft. Unmanned aerial vehicles may be controlled from a remote location. At this remote location, a human operator or a program executed by a computer generates commands for the unmanned aerial vehicle. Unmanned aerial vehicles also may be controlled using a program running on a computer or other controller on the unmanned aerial vehicle. 
     Unmanned aerial vehicles are used for a number of different purposes. In military and security applications, unmanned aerial vehicles may be used to perform missions that may include, for example, without limitation, reconnaissance missions, attack missions, and/or other suitable types of missions. Unmanned aerial vehicles also may be used in a number of civilian applications. For example, without limitation, unmanned aerial vehicles may be used to perform surveying, firefighting, and/or other suitable types of missions. 
     Unmanned aerial vehicles may come in a number of different sizes and shapes. Unmanned aerial vehicles may, for example, take the form of fixed wing aircraft, helicopters, and/or ornithopters. For example, without limitation, an unmanned aerial vehicle may take the form of an airplane, a helicopter, or some other suitable type of device capable of flying. The size of an unmanned aerial vehicle may vary greatly. For example, an unmanned aerial vehicle may have a wing span from about a few inches to about 200 feet, depending on the type of unmanned aerial vehicle. 
     Smaller unmanned aerial vehicles are referred to as micro air vehicles. These types of air vehicles may be configured to be carried by a person and may be launched by throwing the micro air vehicles in the air. The small size of these types of air vehicles allows this type of launching method to provide sufficient velocity for these air vehicles to begin flight. The size of unmanned aerial vehicles has been reduced in part because of a reduction in the sizes of sensors, motors, power supplies, and controllers for these types of vehicles. 
     Reductions in vehicle size and cost make it possible to operate these vehicles in large numbers. For example, micro air vehicles (MAVs) may be operated in numbers that are about the size of a squad or platoon, as compared to operating one or two larger unmanned aerial vehicles. This type of operation increases the monitoring that can be performed for a particular area. These types of unmanned aerial vehicles also may land on a perch, a building, or another location. In this manner, a micro air vehicle may monitor a particular location without having to continue flight. The micro air vehicle may be repositioned if the area of interest changes. 
     For example, a micro air vehicle may land on a building in a city or town. The micro air vehicle may monitor a particular road or building in the city. Micro air vehicles, however, have limitations with their smaller size, as compared to larger unmanned aerial vehicles. For example, the processing power and data transmission ranges may be more limited for micro air vehicles, as compared to larger unmanned aerial vehicles. Further, the range of these micro air vehicles may be shorter, as compared to the larger unmanned aerial vehicles. 
     Various embodiments described herein provide a vehicle base station for autonomous vehicles including unmanned aerial vehicles. In some embodiments, a base station comprises a housing defining at least one platform to support at least one vehicle carrying a payload, a vehicle docking assembly to align the payload at a desired location on the platform, and a payload replacement assembly to remove the payload from the vehicle and to replace the payload with a new payload. Various aspects of embodiments of vehicle base stations and unmanned aerial vehicles will be explained with reference to the figures, below. 
     With reference to  FIG. 1 , an illustration of an unmanned aerial vehicle environment is depicted in accordance with an embodiment. Unmanned aerial vehicle environment  100  includes unmanned aerial vehicle base station  102 , unmanned aerial vehicle base station  104 , and unmanned aerial vehicle base station  106 . 
     In the example depicted in  FIG. 1 , unmanned aerial vehicle base station  102  is located on rooftop  108  of building  110  within a town  112 . Unmanned aerial vehicle base station  104  is associated with vehicle  114 . A first component may be considered to be associated with a second component by being secured to the second component, bonded to the second component, fastened to the second component, and/or connected to the second component in some other suitable manner. The first component also may be connected to the second component by a third component. The first component may be considered to be associated with the second component by being formed as part of and/or an extension of the second component. 
     Unmanned aerial vehicle base station  106  is located on power lines  116 . Unmanned aerial vehicle base stations  102 ,  104 , and  106  may be deployed in a number of different ways. Unmanned aerial vehicle base station  102  may be dropped off by helicopter on rooftop  108 . The location of unmanned aerial vehicle base station  102  on rooftop  108  may result in unmanned aerial vehicle base station  102  being less observable. Further, this location may provide a better line of sight between unmanned aerial vehicle base station  102  and communication arrays. In this manner, the range at which unmanned aerial vehicle base station  102  may communicate with unmanned aerial vehicles may be increased. 
     Unmanned aerial vehicle base station  104  is associated with vehicle  114 . By being associated with vehicle  114 , unmanned aerial vehicle base station  104  may be moved periodically or constantly. This type of deployment may reduce the discoverability of unmanned aerial vehicle base station  104 . Further, by providing mobility to unmanned aerial vehicle base station  104 , greater flexibility may be present for performing missions. In addition, unmanned aerial vehicle base station  104  may be removed from vehicle  114  and placed on the ground or in some other suitable location. 
     Unmanned aerial vehicle base station  106  may be deployed onto power lines  116  by being dropped by a helicopter, on a parachute, or some other suitable mechanism. Unmanned aerial vehicle base station  106  may be less observable on power lines  116 . As depicted, unmanned aerial vehicles, such as unmanned aerial vehicles  118 ,  120 ,  122 ,  124 ,  126 ,  128 ,  130 ,  132 ,  134 ,  136 , and  138  may operate from unmanned aerial vehicle base stations  102 ,  104 , and  106 . 
     In these illustrative examples, unmanned aerial vehicle base stations  102 ,  104 , and  106  provide a base from which the different unmanned aerial vehicles may transmit data, receive instructions, recharge, be stored, and/or perform other operations. 
     Additionally, unmanned aerial vehicles may travel from base station to base station. In other words, unmanned aerial vehicle base stations  102 ,  104 , and  106  may provide a network to extend the range of unmanned aerial vehicles. Having multiple unmanned aerial vehicle base stations also may provide backup in case one unmanned aerial vehicle base station malfunctions or fails to perform as needed. 
     As can be seen in this depicted example, unmanned aerial vehicle base stations  102 ,  104 , and  106  may be placed in locations where detection of those base stations may be reduced. These locations may include other locations other than those illustrated in this particular example. For example, unmanned aerial vehicle base stations  102 ,  104 , and  106  may be placed in trees, in brush, and/or in other suitable locations. 
     The unmanned aerial vehicles may be used to perform a number of different missions in unmanned aerial vehicle environment  100 . In this illustrative example, the unmanned aerial vehicles may monitor for undesired activity. For example, the undesired activity may be the placement of an improvised explosive device in roadway  140 . In another example, the unmanned aerial vehicles may monitor for movement of vehicles or people. In still other examples, unmanned aerial vehicles may be used to monitor for construction of structures. 
     With reference now to  FIG. 2 , an illustration of a block diagram of an unmanned aerial vehicle base station is depicted in accordance with an advantageous embodiment. Unmanned aerial vehicle base station  200  is an example of an unmanned aerial vehicle base station that may be used to implement unmanned aerial vehicle base stations  102 ,  104 , and  106  in  FIG. 1 . 
     In this illustrative example, unmanned aerial vehicle base station  200  comprises platform  202 , battery system  204 , power generation system  206 , number of charging stations  208 , controller  210 , sensor system  212 , and/or other suitable components. 
     Platform  202  is configured to hold one or more unmanned aerial vehicles  214 . In other words, number of unmanned aerial vehicles  214  may be placed in and/or stored in or on platform  202 . For example, platform  202  may have bay  216  in which number of unmanned aerial vehicles  214  may land. Bay  216  may be an area of platform  202  surrounded by walls with an opening on the top side of platform  202 . In other advantageous embodiments, bay  216  may have walls and a roof with an opening on the side of platform  202 . An unmanned aerial vehicle is considered to be housed when the unmanned aerial vehicle enters into or lands on platform  202 . 
     Additionally, platform  202  may be configured to provide protection from environment  224  for number of unmanned aerial vehicles  214  when number of unmanned aerial vehicles  214  is housed in platform  202 . 
     Platform  202  also may have movable cover system  218  that is configured to move between open position  220  and closed position  222 . Movable cover system  218  may cover bay  216 . When movable cover system  218  is in open position  220 , number of unmanned aerial vehicles  214  may take off from and/or land in or on platform  202 . 
     When movable cover system  218  is in closed position  222 , number of unmanned aerial vehicles  214  located in bay  216  of platform  202  may be protected from environment  224 . Further, closed position  222  also provides a configuration for transporting number of unmanned aerial vehicles  214  in unmanned aerial vehicle base station  200 . 
     Battery system  204  and power generation system  206  provide electrical energy  226  for unmanned aerial vehicle base station  200  and number of unmanned aerial vehicles  214 . Battery system  204  is optional and stores electrical energy  226  generated by power generation system  206 . Power generation system  206  generates electrical energy  226  from environment  224  in which unmanned aerial vehicle base station  200  is located. 
     A number of charging stations  208  are connected to battery system  204 . Charging stations  208  are configured to charge batteries for a number of unmanned aerial vehicles  214  using electrical energy  226 . Further, charging stations  208  provide electrical energy  226  to controller  210  and sensor system  212  in unmanned aerial vehicle base station  200 . 
     In some embodiments, aerial vehicles  214  may take the form of liquid fueled unmanned aerial vehicles. In these illustrative examples, charging stations  208  is configured to refuel these liquid fueled unmanned aerial vehicles. For example, unmanned aerial vehicle base station  200  may have liquid refueling system  244 . Liquid refueling system  244  has liquid fuel tank  246  containing liquid fuel. The liquid fuel may be, for example, gasoline or diesel fuel. Pump  248  in liquid refueling system  244  transfers the liquid fuel in liquid fuel tank  246  to number of charging stations  208 . Charging stations  208  may be configured to provide liquid fuel to the liquid fuel unmanned aerial vehicles. 
     In these embodiments, controller  210  may be configured to control the pumping of liquid fuel from liquid refueling system  244 . In some embodiments, liquid refueling system  244  may deliver liquid fuel to one or more unmanned aerial vehicles  214  at number of charging stations  208  using a syringe injection system. 
     In these embodiments, controller  210  may be configured to receive sensor data  236  from number of unmanned aerial vehicles  214 . Additionally, controller  210  may be configured to generate information  238  from sensor data  236 . Information  238  may then be sent to remote location  240 . Remote location  240  is a location remote to unmanned aerial vehicle base station  200 . The remote location may include a mission planning system or a human operator. Controller  210  may also be configured to program each of number of unmanned aerial vehicles  214  with mission  242 . Mission  242  may be the same or different for each of number of unmanned aerial vehicles  214 . 
     Sensor system  212  generates sensor data  248  from environment  224 . Sensor data  248  may be sent to remote location  240  or may be used to send commands  250  to number of unmanned aerial vehicles  214 . 
     The illustration of unmanned aerial vehicle base station  200  in  FIG. 2  is not meant to imply physical or architectural limitations to the manner in which different advantageous embodiments may be implemented. Other components in addition to and/or in place of the ones illustrated may be used. Some components may be unnecessary in some advantageous embodiments. Also, the blocks are presented to illustrate some functional components. One or more of these blocks may be combined and/or divided into different blocks when implemented in different embodiments. 
     For example, in some embodiments, different forms of energy may be stored in storage devices for conversion into electrical energy for number of unmanned aerial vehicles  214 . These storage devices may be devices other than battery system  204 . These devices may include, for example, without limitation, capacitors, flywheels, compressed air devices, and/or other suitable energy storage devices. One or more of these devices may be connected to charging stations  208 . In some embodiments a base station may comprise a system to replace a battery pack (or other payload) on a vehicle. Further, a base station may comprise an assembly to recharge one or more batteries. Embodiments of such base station are described below with reference to  FIGS. 8A and 8B . 
     Turning to  FIG. 3 , an illustration of a block diagram of a data processing system is depicted in accordance with an embodiment. Data processing system  300  is an example of an implementation for controller  210  in  FIG. 2 . In this illustrative example, data processing system  300  includes communications fabric  302 , which provides communications between processor unit  304 , memory  306 , persistent storage  308 , communication unit  310 , and input/output (I/O) unit  312 . 
     Processor unit  304  serves to execute instructions for software that may be loaded into memory  306 . Processor unit  304  may be a set of one or more processors or may be a multi-processor core, depending on the particular implementation. Further, processor unit  304  may be implemented using one or more heterogeneous processor systems in which a main processor is present with secondary processors on a single chip. As another illustrative example, processor unit  304  may be a symmetric multi-processor system containing multiple processors of the same type. 
     Memory  306  and persistent storage  308  are examples of storage devices  316 . A storage device is any piece of hardware that is capable of storing information, such as, for example, without limitation, data, program code in functional form, and/or other suitable information either on a temporary basis and/or a permanent basis. Memory  306 , in these examples, may be, for example, a random access memory or any other suitable volatile or non-volatile storage device. 
     Persistent storage  308  may take various forms, depending on the particular implementation. For example, persistent storage  308  may contain one or more components or devices. For example, persistent storage  308  may be a hard drive, a flash memory, a rewritable optical disk, a rewritable magnetic tape, or some combination of the above. The media used by persistent storage  308  may be removable. For example, a removable hard drive may be used for persistent storage  308 . 
     Communication unit  310 , in these examples, provides for communication with other data processing systems or devices. In these examples, communications unit  310  is a network interface card. Communications unit  310  may provide communications through the use of either or both physical and wireless communications links. 
     Communications unit  310  is configured to provide wireless communications links. These wireless communications links may include, for example, without limitation, a satellite communications link, a microwave frequency communications link, a radio frequency communications link, and/or other suitable types of wireless communication links. 
     Input/output unit  312  allows for the input and output of data with other devices that may be connected to data processing system  300 . For example, input/output unit  312  may provide a connection for user input through a keyboard, a mouse, and/or some other suitable input device. Further, input/output unit  312  may send output to a printer. Display  314  provides a mechanism to display information to a user. 
     Instructions for the operating system, applications, and/or programs may be located in storage devices  316 , which are in communication with processor unit  304  through communications fabric  302 . In these illustrative examples, the instructions are in a functional form on persistent storage  308 . These instructions may be loaded into memory  306  for execution by processor unit  304 . The processes of the different embodiments may be performed by processor unit  304  using computer implemented instructions, which may be located in a memory, such as memory  306 . 
     These instructions are referred to as program code, computer usable program code, or computer readable program code that may be read and executed by a processor in processor unit  304 . The program code, in the different embodiments, may be embodied on different physical or computer readable storage media, such as memory  306  or persistent storage  308 . 
     Program code  318  is located in a functional form on computer readable media  320  that is selectively removable and may be loaded onto or transferred to data processing system  300  for execution by processor unit  304 . Program code  318  and computer readable media  320  form computer program product  322 . In one example, computer readable media  320  may be computer readable storage media  324  or computer readable signal media  326 . 
     Computer readable storage media  324  may include, for example, an optical or magnetic disk that is inserted or placed into a drive or other device that is part of persistent storage  308  for transfer onto a storage device, such as a hard drive, that is part of persistent storage  308 . Computer readable storage media  324  also may take the form of a persistent storage, such as a hard drive, a thumb drive, or flash memory that is connected to data processing system  300 . In some instances, computer readable storage media  324  may not be removable from data processing system  300 . 
     Alternatively, program code  318  may be transferred to data processing system  300  using computer readable signal media  326 . Computer readable signal media  326  may be, for example, a propagated data signal containing program code  318 . For example, computer readable signal media  326  may be an electromagnetic signal, an optical signal, and/or any other suitable type of signal. These signals may be transmitted over communication links, such as wireless communications links, an optical fiber cable, a coaxial cable, a wire, and/or any other suitable type of communication link. In other words, the communication link and/or the connection may be physical or wireless in the illustrative examples. 
     In some embodiments, program code  318  may be downloaded over a network to persistent storage  308  from another device or data processing system through computer readable signal media  326  for use within data processing system  300 . For instance, program code stored in a computer readable storage media in a server data processing system may be downloaded over a network from the server to data processing system  300 . The data processing system providing program code  318  may be a server computer, a client computer, or some other device capable of storing and transmitting program code  318 . 
     The different components illustrated for data processing system  300  are not meant to provide architectural limitations to the manner in which different embodiments may be implemented. The different illustrative embodiments may be implemented in a data processing system, including components in addition to or in place of those illustrated for data processing system  300 . Other components shown in  FIG. 3  can be varied from the illustrative examples shown. The different embodiments may be implemented using any hardware device or system capable of executing program code. As one example, data processing system  300  may include organic components integrated with inorganic components and/or may be comprised entirely of organic components excluding a human being. For example, a storage device may be comprised of an organic semiconductor. 
     As another example, a storage device in data processing system  300  is any hardware apparatus that may store data. Memory  306 , persistent storage  308 , and computer readable media  320  are examples of storage devices in a tangible form. 
     In another example, a bus system may be used to implement communications fabric  302  and may be comprised of one or more buses, such as a system bus or an input/output bus. Of course, the bus system may be implemented using any suitable type of architecture that provides for a transfer of data between different components or devices attached to the bus system. Additionally, a communications unit may include one or more devices used to transmit and receive data, such as a modem or a network adapter. Further, a memory may be, for example, memory  306  or a cache such as found in an interface and memory controller hub that may be present in communications fabric  302 . 
     With reference to  FIG. 4 , an illustration of a block diagram of a power generation system is depicted in accordance with an advantageous embodiment. Power generation system  400  is an example of one implementation for power generation system  206  in  FIG. 2 . Power generation system  400  generates electrical energy  401  in these illustrative examples. 
     Power generation system  400  may include energy harvesting system  402 . Energy harvesting system  402  may comprise at least one of solar power generation unit  404 , inductive power generation unit  406 , wind power generation unit  408 , and/or other suitable types of energy harvesting units. Power generation system  400  also may include radioisotope thermal electrical generation unit  410 , power converter  412 , and/or other suitable types of power generation devices, e.g., fuel cells, batteries, electric generators, or electric outlets. 
     As used herein, the phrase “at least one of”, when used with a list of items, means that different combinations of one or more of the listed items may be used and only one of each item in the list may be needed. For example, “at least one of item A, item B, and item C” may include, for example, without limitation, item A or item A and item B. This example also may include item A, item B, and item C, or item B and item C. In other examples, “at least one of” may be, for example, without limitation, two of item A, one of item B, and 10 of item C; four of item B and seven of item C; and other suitable combinations. 
     Solar power generation unit  404  generates electrical energy  401  from exposure to sunlight or other light in the environment. Solar power generation unit  404  may comprise solar energy cells  416 . In the different illustrative examples, solar energy cells  416  may take the form of photovoltaic units. Solar energy cells  416  may be located on, for example, without limitation, movable cover system  218  in  FIG. 2 . 
     Inductive power generation unit  406  generates power inductively when an alternating current source is present, such as in power lines. This power may be used to provide electrical energy  401 . Wind power generation unit  408  may include a number of wind power turbines that generate electrical energy  401  from wind that may be present in the environment. 
     Radioisotope thermal electrical generation unit  410  generates electrical energy  401  from radioactive material that decays. The decay of the radioactive material generates heat used by radioisotope thermal electrical generation unit  410  to generate electrical energy  401 . This radioactive material is carried by the unmanned aerial vehicle base station in these examples. 
     Power converter  412  converts electrical power from one form to another form. For example, power converter  412  may convert alternating current (AC) energy into direct current (DC) energy. Power converter  412  also may change the frequency of alternating current energy as another example. In yet another example, power converter  412  may change the current flow. Power converter  412  may be used when a power source, such as an electrical outlet, is present. In these illustrative examples, power converter  412  converts energy into electrical energy  401  for use by an unmanned aerial vehicle. 
     Referring now to  FIG. 5 , an illustration of a block diagram of a sensor system is depicted in accordance with an advantageous embodiment. Sensor system  500  is an example of one implementation for sensor system  212  in  FIG. 2 . In these illustrative examples, sensor system  500  generates sensor data  501 . Sensor system  500 , in this example, includes camera system  502 , global positioning system unit  504 , weather sensors  506 , and motion detector  508 . 
     Camera system  502  may comprise number of cameras  510 . Cameras  510  may include at least one of visible light camera  512 , infrared camera  514 , and other suitable types of cameras. In some advantageous embodiments, visible light camera  512  and infrared camera  514  are combined as part of a multispectral camera. 
     Camera system  502  generates sensor data  501  in the form of image data  518 . Global positioning system unit  504  generates location information  520  in sensor data  501 . Location information  520  may include, for example, latitude, longitude, and an elevation. Additionally, time information  522  also may be generated by global positioning system unit  504 . 
     Weather sensors  506  generate weather data  524  in sensor data  501  that may be used to identify weather conditions. For example, weather sensors  506  may generate information about wind speed, pressure, wind direction, humidity, temperature, and/or other suitable information. 
     Motion detector  508  generates motion data  526  in sensor data  501 . Motion detector  508  generates motion data  526  when motion in an area monitored by motion detector  508  is detected. 
     Turning now to  FIG. 6 , an illustration of a block diagram of a charging station is depicted in accordance with an advantageous embodiment. Charging station  600  is an example of an implementation for a charging station within number of charging stations  208  in  FIG. 2 . 
     Charging station  600  may comprise at least one of inductive charging system  602  and conductive charging system  604 . Inductive charging system  602  generates magnetic field  606 . Magnetic field  606  may induce another magnetic field in a coil located within the device being charged. In this manner, the current may be caused to flow in the device being charged without contact between inductive charging system  602  and the device. 
     Conductive charging system  604  includes contacts  608 . Contacts  608  may be placed in physical contact with contacts on the device being charged. This contact allows for electrical current  610  to flow from conductive charging system  604  to the device being charged by charging station  600 . In this manner, the device may be charged and/or recharged to perform additional operations or missions. 
     Turing now to  FIG. 7 , an illustration of a block diagram of an unmanned aerial vehicle is depicted in accordance with an advantageous embodiment. Unmanned aerial vehicle  700  is an example of one implementation for number of unmanned aerial vehicles  214  in  FIG. 2 . In some embodiments the vehicles may include manned aerial vehicles or vehicles other than aerial vehicles, e.g., ground vehicles such as cars, trucks, tanks, or the like. 
     In this illustrative example, unmanned aerial vehicle  700  may take a number of forms. For example, unmanned aerial vehicle  700  may be, for example, without limitation, airplane  702 , helicopter  704 , ornithopter  706 , or some other suitable type of aircraft. 
     As illustrated, unmanned aerial vehicle  700  comprises body  708 , propulsion system  710 , battery  712 , charging system  714 , processor unit  716 , storage device  718 , wireless communications device  720 , and number of sensors  722 . Body  708  provides a structure in which the different components of unmanned aerial vehicle  700  may be associated with each other. For example, without limitation, body  708  may be a fuselage. Further, body  708  may include aerodynamic surfaces, such as wings or other types of surfaces. 
     Propulsion system  710  is configured to move unmanned aerial vehicle  700  in the air. Propulsion system  710  may be, for example, without limitation, an electric motor configured to rotate a propeller or other type of blade. In other advantageous embodiments, propulsion system  710  may be configured to move wings on body  708  when unmanned aerial vehicle  700  takes the form of ornithopter  706 . Battery  712  provides electrical energy for unmanned aerial vehicle  700 . 
     Charging system  714  is connected to battery  712  and allows battery  712  to be recharged at a charging station. Charging system  714  may include inductive coils for an inductive charging system or conductive contacts for a conductive charging system. In some advantageous embodiments, charging system  714  also may be used to transfer data. As one illustrative example, charging system  714  may provide a modulated charge as a carrier frequency. This modulated charge allows for the transfer of data in addition to the providing of power. 
     As another illustrative example, conductive contacts in charging system  714  may be used to transfer data. In other advantageous embodiments, power may be provided wirelessly by charging system  714  using microwaves or a laser. 
     Processor unit  716  runs a number of programs for missions in these illustrative examples. Storage device  718  may store sensor data  724  generated by sensors  722 . Additionally, storage device  718  may store mission  726  that is executed or run by processor unit  716 . Mission  726  may be, for example, without limitation, a program, an identification of a target, and/or other suitable types of information. 
     Wireless communication device  720  is configured to provide communications between unmanned aerial vehicle  700  and a remote location, such as unmanned aerial vehicle base station  200  or remote location  240  in  FIG. 2 . In these illustrative examples, number of sensors  722  may include, for example, at least one of visible light camera  728 , infrared light camera  730 , motion detector  732 , and/or other suitable types of sensors used to generate sensor data  724  for processing by processor unit  716 . 
     The illustration of unmanned aerial vehicle base station  200  and its components in  FIGS. 2-6  and unmanned aerial vehicle  700  in  FIG. 7  are not meant to imply physical or architectural limitations to the manner in which different advantageous embodiments may be implemented. Other components in addition to and/or in place of the ones illustrated may be used. Some components may be unnecessary in some advantageous embodiments. Also, the blocks are presented to illustrate some functional components. One or more of these blocks may be combined and/or divided into different blocks when implemented in different advantageous embodiments. 
     For example, in some embodiments, unmanned aerial vehicle base station  200  may not include movable cover system  218 . Instead, bay  216  may be configured to provide protection from environment  224  without moving parts. For example, bay  216  may be a cavity in platform  202  with an opening configured to protect number of unmanned aerial vehicles  214  from environment  224 . Additionally, in some embodiments, unmanned aerial vehicle  700  may not have wireless communications device  720 . Instead, a wired contact may be used to transfer data from unmanned aerial vehicle  700  to unmanned aerial vehicle base station  200  when unmanned aerial vehicle  700  lands on platform  202 . 
     In some embodiments a vehicle base station may be adapted to include an assembly for automatically removing a payload from a vehicle and replacing the payload. In embodiments described herein the payload comprises a modular battery case which is selectably attachable to a battery receptacle on the vehicle. Further, the vehicle base station may be adapted to recharge batteries removed from the vehicles. 
     One embodiment of a vehicle base station  800  depicted in  FIG. 8A  and  FIG. 8B .  FIG. 8A  is an illustration of a side cross-sectional view of a vehicle base station  800 , and  FIG. 8B  is an illustration of a top cross-sectional view of a vehicle base station  800  in accordance with embodiments. In some embodiments, a vehicle base station  800  comprises a housing  810  defining at least one platform  820  to support at least one vehicle  830  carrying a payload  840 , a vehicle docking assembly  850  to align the payload  840  at a desired location on the platform  820 , and a payload replacement assembly  860  to remove the payload  840  from the vehicle  830  and to replace the payload  840  with a new payload  840 . 
     Referring to  FIG. 8A  and  FIG. 8B , in some embodiments the housing  810  comprises a base  812 , walls  814  and a platform  820  which define an internal chamber. An aperture  822  in the platform  820  provides access to the internal chamber. The dimensions of the housing  810  are not critical, and may be a function of the size of vehicle  830  for which the housing  810  is adapted. For smaller vehicles such as the micro air vehicles described above the housing may be dimensioned such that it is readily portable. For larger vehicles, e.g., unmanned aerial vehicles or manned aerial vehicles the housing  810  would need to be larger. 
     A vehicle  830  such as, e.g., an aircraft or an automobile, may be positioned on the platform  820 . In the embodiment depicted in  FIG. 8A  the vehicle  830  is an unmanned aerial vehicle comprising a body  832 , a frame structure  834 , rotors  836  and supports  838 . 
     In some embodiments a vehicle docking assembly  850  is coupled to the platform  820  to secure the vehicle  820  in an appropriate location above the aperture  822  in the platform. In the embodiment depicted herein the vehicle docking assembly  850  comprises an alignment mechanism to align the vehicle in a predetermined position on the platform. By way of example, the vehicle docking assembly  850  may comprise one or more electromagnetic pads  850  positioned on the surface of the platform  820 . When activated, electromagnetic pads  850  generate a magnetic force to secure the supports  838  of the vehicle  830  to the platform  820 . 
     A payload replacement assembly  860  is positioned within the chamber defined by the housing  810 . In the embodiment depicted in  FIGS. 8A and 8B  the payload replacement assembly  860  comprises a hoist assembly  862  which raises a payload platform  864  from a first position, as illustrated in  FIG. 8A , in which the payload platform  862  is displaced from a payload  840  to a second position in which the payload platform contacts a payload  840  mounted on the vehicle  830 . The hoist assembly  860  may be actuated by a conventional motor  866 . 
     A payload advancing assembly  870  cooperates with the payload replacement assembly to receive a payload  840  from the vehicle  830  and to advance a payload  840  into a position from which the payload may be hoisted onto the vehicle  830 . In the embodiment depicted in  FIGS. 8A and 8B  the payload advancing assembly comprises a turntable  872  which rotates about a central axis. The platform comprises a plurality of docking stations  874  to hold a payload  840 . In some embodiments the docking stations  874  define an aperture in the turntable  872  through which the payload platform  864  may pass when the hoist assembly  860  raises the payload platform  864  to contact the payload  840 . Thus, referring to  FIG. 8B , the payload platform  864  is visible through the aperture in the docking station  874  of the turntable  872 . 
     While the specific composition of the payload  840  is not critical, in some embodiments the payload  840  may comprise one or more batteries from which the vehicle  830  draws power. In such embodiments the docking stations  874  may comprise or be coupled to a battery charging substation such that batteries removed from the vehicle  830  may be recharged while they are positioned on the turntable  872 . 
     In some embodiments one or more batteries for the vehicle  830  may be stored within a modular battery pack that is adapted to engage with a receptacle that may be coupled to the vehicle  830 .  FIG. 9A  is a perspective view of a modular battery pack  900  according to embodiments. Referring to  FIG. 9A , a modular battery pack  900  may comprise a lower portion  910  and an upper portion  920 , which define an internal chamber into which one or more batteries may be placed. The upper surface  922  of the upper portion  920  comprises one or more alignment pins  924  and one or more locking anchors  930  which facilitate coupling the battery pack  900  to a receptacle  940  (See  FIG. 9B ) mounted on the vehicle  830 . 
       FIGS. 9B-9D  are illustrations of perspective views of a modular battery case  900  and a battery receptacle  940  in accordance with embodiments. Referring to  FIGS. 9B-9D , the battery receptacle  940  comprises four walls  942  and a top  944  which define an open-bottomed chamber to receive a battery pack  900 . The top  944  comprises one or more holes  948  to receive the alignment pins  924  and one or more locking components  946  to receive the locking anchors  930  on the battery pack. 
       FIG. 9E  is a schematic, perspective view of a locking anchor  930  and a locking component  946 , according to embodiments. Referring briefly to  FIG. 9E , the locking anchor  930  may be coupled to the locking component  946 , the jaws  948  of which close and lock onto the locking anchor  930 . When the engagement/disengagement button  950  is depressed the jaws release the locking anchor  930 . 
     Having described various structural components of an example vehicle base station, methods of using such a base station will now be describe. In some embodiments a vehicle base station as described herein may be used to implement a method to replace a payload  840  on a vehicle  830 , which will be described with reference to  FIG. 10 . 
     In use, a vehicle such as vehicle  830  is positioned (operation  1010 ) on the platform  820  of the housing  810 . In the case of an airborne vehicle such as a UAV or an MAV, the airborne vehicle may be landed directly on the platform. Alternatively, the airborne vehicle may be landed elsewhere and manually positioned on the platform  820 . In the case of a land-based vehicle the vehicle may be driven directly onto the platform  820  or may be driven near the platform then manually positioned on the platform  820 . 
     When the vehicle  830  is positioned on the platform the alignment assembly  850  may be activated to align the payload  840  over the aperture  822  in the platform  820 . In the embodiment depicted in  FIG. 8A  the electromagnetic pads  850  may be activated to position and secure the vehicle  830  over the aperture  822  in the platform  820 . 
     At operation  1015  an empty docking station is aligned with the aperture  822  in the platform  820 . In the embodiment depicted in  FIGS. 8A and 8B , the rotating turntable  872  may be advanced such that an empty docking station  874  is beneath the aperture  822  in the platform. When the rotating turntable is in this position the payload platform  864  is positioned underneath the empty docking station. 
     At operation  1020  the first payload  840  is removed from the vehicle  830 . In the embodiment depicted in  FIGS. 8A and 8B  the hoist assembly  862  raises the payload platform  864  through the empty docking station  874  in the turntable  872  such that the payload platform  864  contacts the payload  840  on the vehicle. In embodiments in which the payload comprises a modular battery case  900  as described with reference to  FIGS. 9A-9E  the payload platform  864  applies pressure to the modular battery case  900 , which cases the locking anchor  930  to depress the engagement/disengagement button  950  on the locking component  946 . This, in turn, causes the jaws  948  of the locking component to release the locking anchor  930 , thereby automatically releasing the payload  840  from the vehicle. The payload  830  then rests on the payload platform  864 . 
     At operation  1025  the payload  840  removed from the vehicle in operation  1020  is placed in an empty docking station  874 . In the embodiment depicted in  FIGS. 8A and 8B  the hoist assembly  862  lowers the payload platform  864  through the empty docking station  874  in the turntable  872 . In some embodiments the modular battery case  900  is dimensioned such that it is smaller than the aperture in the empty docking station  874 , such that the modular battery case passes through the aperture in the empty docking station. 
     At operation  1030  the payload advancing assembly is advanced to position a new payload  840  in the aperture  822  beneath the vehicle  830  on the platform  820 . In the embodiment depicted in  FIGS. 8A and 8B  the turntable  872  is rotated to position a new payload  840  in the aperture  822  beneath the vehicle  830 . 
     At operation  1035  the new payload is secured to the vehicle. In the embodiment depicted in  FIGS. 8A and 8B  the hoist assembly raises the payload platform  864  through the docking station  874  in the turntable  872  such that the payload is lifted off the payload platform  864  and up to the vehicle  830 . In embodiments in which the payload comprises a modular battery case  900  as described with reference to  FIGS. 9A-9E  the payload platform  864  applies pressure to the modular battery case  900 , which causes the locking anchor  930  to depress the engagement/disengagement button  950  on the locking component  946 . This, in turn, causes the jaws  948  of the locking component to lock onto the locking anchor  930 , thereby automatically securing the payload  840  to the vehicle  830 . The payload platform  864  may then be lowered back through the docking station  874  in the turntable  872 . 
     As described above, in some embodiments the payload  840  may comprise at least one battery. In such embodiments the base station  800  may comprise, or be coupled to, a battery charging station to recharge batteries removed from the vehicle  830 . By way of example and not limitation in some embodiments the docking stations  874  in the turntable  872  may comprise a battery charging terminal such that batteries stored in the docking stations  874  are charged. In such embodiments the modular battery case  900  is larger than the aperture in the empty docking station  874 , such that the modular battery case  900  is positioned in docking station  874  on the turntable  872  when the payload platform  846  drops through the aperture in the empty docking station  874 . The battery may then be charged while it is positioned in the docking station  874 . 
     Thus, described herein are exemplary embodiments of a vehicle loading station and associated methods for using a vehicle loading station. In some embodiments the vehicle loading station comprises a housing which defines at least one platform onto which a vehicle carrying a payload may be positioned. A vehicle docking assembly docks and secures the vehicle on the platform. A payload replacement assembly removes a payload from the vehicle and replaced with a new payload. 
     In some embodiments the payload  840  may comprise one or more batteries. In other embodiments the payload  840  may comprise a transport payload, e.g., materials or goods. In other embodiments the payload  840  may comprise a dispensable payload such as water or a fire suppressant. 
     Reference in the specification to “one embodiment” or “some embodiments” means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least an implementation. The appearances of the phrase “in one embodiment” in various places in the specification may or may not be all referring to the same embodiment. 
     Although embodiments have been described in language specific to structural features and/or methodological acts, it is to be understood that claimed subject matter may not be limited to the specific features or acts described. Rather, the specific features and acts are disclosed as sample forms of implementing the claimed subject matter.