Patent Publication Number: US-2023150625-A1

Title: Unmanned Aerial Vehicle Search and Rescue System

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     The present application is a continuation-in-part of U.S. Application Serial No. 17/391,293 entitled Unmanned Aerial Vehicle Search and Rescue System, filed on Aug. 2, 2021 which is a divisional of U.S. Application Serial No. 16/380,446 entitled Unmanned Aerial Vehicle Search and Rescue System, filed on Apr. 10, 2019, which is a continuation-in-part of U.S. Application Serial No. 16/045,137 entitled Unmanned Aerial Vehicle Search and Rescue System, filed on Jul. 25, 2018. All of the foregoing applications are hereby incorporated by reference in their entireties. 
    
    
     BACKGROUND OF THE INVENTION 
     Unmanned aerial vehicles (hereinafter “UAVs” or “drones”) are becoming ubiquitous, and are increasingly being deployed for many different uses and tasks. Recently, UAVs have been used by lifeguards at beaches to monitor swimmers, and in one case, a UAV was equipped with a mechanism for dropping a life preserver to save a swimmer in distress. Along those lines, UAVs may be particularly helpful in man-overboard situations, along with other swimmer-in-distress events. There are many reported cases of people disappearing from cruise ships, and in such an event, a UAV is highly useful for conducting search and rescue operations because it can be quickly and easily deployed directly from the ship, provides a bird’s eye view over a large area, and can quickly cover large distances in a short period of time. A search and rescue drone could be used on commercial fishing vessels and other types of boats and ships, particularly including those that routinely operate in bad weather conditions. In a man overboard situation, time is critical, especially in colder waters, where life expectancy may be around 15 minutes before hypothermia and even death occurs. Thus, the ability to deploy a search and rescue drone to quickly locate and provide assistance to a swimmer in distress could mean the difference between life and death. 
     Efforts are underway to develop UAVs specifically for search and rescue operations, particularly involving water rescue operations. The following references show several examples of such development efforts for UAVs, and these references are incorporated herein by reference, in their entireties: 
     US Application Publication No. US20150066248 - Unmanned Vehicle Searches 
     A method of planning a flight path for a search can include receiving, by a control system, an indication of a search area boundary; receiving, by the control system, an indication of a selected search pattern; determining, by the control system, a flight path based on the search area boundary and the selected search pattern; and transmitting one or more indications of the flight path to an unmanned aerial vehicle. 
     US Application Publication No. US20160340006- Unmanned Aerial Vehicle System and Methods for Use 
     A drone equipped with a camera, a wireless communication module, an acoustic sensor, a GPS receiver, software and collapsible floatation device patrols above swimmers. The camera and acoustic sensor capture the video and audio of the swimmers. The information is either streamed to a command center or processed by the onboard software. With audio and video analysis capabilities, software is used to detect a swimmer in distress (SID). Alternatively the information is streamed to lifeguard or volunteers all over the world to spot SID. 
     Another detection method is to let a swimmer wear a wearable emergency notification device, which sends wireless signals comprising GPS location data. A SID presses a button to indicate rescue request and the drones fly over by GPS signal guidance. Solar power is used as the optional power source of the drones, which would allow the to sustain operation for a prolonged period of time. Once a SID is identified, the drone or drones fly over the SID and drops the collapsible floatation device. 
     US Application Publication No. US20170088261- Search and Rescue UAV System and Method 
     An unmanned aerial vehicle (UAV) having at least one sensor for detecting the presence of a survivor in a search and rescue area. The at least one sensor is preferably an ultra-wide band (UWB) transceiver sensor. The UAV includes a UAV data link transceiver for wirelessly communicating information concerning the survivor to a command center. 
     US Application Publication No. US20170210451- Drone-Type Lifesaving Equipment Dropping Device 
     A drone-type lifesaving equipment dropping device including: an unmanned aerial vehicle (2) having a propeller (4) and a rotor (3) configured to rotate the propeller; a holding member (10) which is installed to the unmanned aerial vehicle (2) and configured to be operated by wireless control; and a lifesaving equipment which is detachably engaged to the holding member (10) and is dropped from the holding member (10) after the lifesaving equipment is disengaged from the holding member. 
     Although each of the above-referenced systems is useful for search and rescue operations, and several of these systems may be used to deliver a flotation device or life preserver, none of the prior references discloses a UAV that is buoyant so that the UAV is, itself, a flotation device to assist a swimmer in distress (SID). Therefore, it would be desirable to provide a UAV that serves as a mobile life preserver, which is capable of landing on water and taking off from water, and which includes electronics for determining its position and transmitting an SOS signal, similarly to an emergency position-indicating radio beacon (EPIRB). Further, it would be advantageous, in man overboard types of situations, to provide the search and rescue drone with flashing lights, a spotlight, a camera and other sensors for locating a swimmer in distress, along with the capability for the UAV to autonomously fly along the same path (in reverse) that the boat was traveling when the man overboard situation occurred. Additionally, it would be advantageous to provide an electronic wearable device having the capability to communicate with the search and rescue drone, so that the drone may autonomously track the wearable device and fly to its location in an emergency situation. 
     BRIEF SUMMARY OF THE INVENTION 
     In accordance with one aspect of the invention, one embodiment of a search and rescue drone includes a buoyant body member, a frame attached to the buoyant body member for carrying a motor and propeller, and an electronic array including a camera, GPS, an EPIRB, and a transmitter/receiver for manually flying the drone and communicating with an operator. 
     The search and rescue drone may be flown manually, or may have some autonomous flight and locator capabilities. For example, in one embodiment, the search and rescue drone may be programmed to simply fly to the location of an electronic wearable device, like a bracelet, that is worn by a person on a boat. The wearable device may be automatically activated upon immersion in water, or may be manually activated (by pressing a button on the device, or by giving voice commands, for instance), but in either circumstance, the activation of the wearable device triggers the search and rescue drone to automatically fly to the location of the wearable device and land nearby, so that the SID may hold onto it for purposes of flotation. Preferably, the search and rescue drone is equipped with flashing strobe lights or other emergency lights that are used as a visual signal for help to get the attention of a search and rescue party. Also, the EPIRB on board transmits a distress signal, along with GPS coordinates of its present location, when the search and rescue drone lands in the water. 
     In another embodiment, the search and rescue drone includes a basket, harness, or other means for actually recovering a swimmer in distress, and flying that person back to a ship or to shore. In this embodiment, the drone may either land in the water so that a swimmer in distress may climb aboard, or the drone may lower a basket or harness down to the swimmer while the drone hovers overhead. In either embodiment, the drone may be equipped with a button or other means for indicating that the swimmer is safely aboard the basket or is engaged within the harness, which then triggers the drone to fly the swimmer back to safety. 
     When used on board a boat or ship, the search and rescue drone may be programmed to execute a specific search pattern, which may include flying to a designated altitude and following the same path, in reverse, that the boat was traveling when the man-overboard event occurred. The onboard GPS unit may either do its own tracking while the boat is underway, so that it is always tracking its own position and has that information available when deployed in an emergency, or the system may include a communications link with the GPS system on board the ship so that the search and rescue drone may query the shipboard GPS to obtain that information. 
     In another embodiment, the search and rescue drone may include two main parts: the flying portion and the floating portion. The flying portion preferably includes a frame, the motor and propeller, camera(s), flashing lights, a spotlight (optionally) and a transmitter/receiver for sending and receiving communications. The floating portion is used as a life preserver, and preferably includes an EPIRB to transmit an SOS message, along with GPS coordinates. In this embodiment, the drone may land on the water as a single unit, and then separate so that the flying portion can hover overhead while displaying the flashing lights, spotlight (if necessary), and acting as a communications booster by relaying and broadcasting the EPIRB signal to potential rescuers. 
     Alternatively, after locating the swimmer in distress, the drone may separate in the air by disconnecting itself from the floating portion, so that the floating portion drops to the water near the swimmer. It is preferred that the EPIRB remain with the floating portion (and the swimmer) rather than the flying portion, because if the flying portion then crashes, runs out of fuel or electricity, or otherwise becomes separated from the swimmer, the EPIRB continues to broadcast the SOS signal from the swimmer’s location. 
     Other embodiments include simpler versions, where the rescue drone is simply a flying life preserver, wherein the main body member is buoyant, and motors and propellers are positioned within holes defined by the main body member. These types of rescue drones are typically used by beach lifeguards, and the like, and operate via remote control. If a lifeguard sees a swimmer in distress, then he or she can simply launch the flying life preserver and land it adjacent the swimmer in distress for flotation until help arrives. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       These and other features, aspects, and advantages of the present invention will become better understood with regard to the following description, appended claims, and accompanying drawings where: 
         FIG.  1    is a perspective view of one embodiment of a lifesaving unmanned aerial vehicle, having a generally rectangular body member that is buoyant, a series of handle members disposed about the body member for grasping and carrying, and a plurality of motors and propellers disposed within holes defined by the body member; 
         FIG.  2 A  is a side view of another embodiment of a lifesaving unmanned aerial vehicle, including a floating portion, a frame, a series of motors and propellers, an EPIRB, a camera, downwardly pointing flood lights and a pair of strobe lights, and further including a docking station that also serves to recharge the on-board batteries; 
         FIG.  2 B  is a side view of the embodiment of a lifesaving unmanned aerial vehicle as shown in  FIG.  2 A , wherein the vehicle is shown in a docked position with the docking station for storage, transport, and recharging; 
         FIG.  3    is a perspective view of another embodiment of a lifesaving unmanned aerial vehicle, wherein the body member is formed into the shape of a ring, and the motors and propellers are disposed within holes defined by the body member; 
         FIG.  4    is a perspective view of another embodiment of a lifesaving unmanned aerial vehicle, wherein the vehicle includes a winch attached on an underside thereof, with a cable extending downwardly to a harness that is attached to a basket for transporting a person from the water to safety; 
         FIG.  5    is a side view of an alternate embodiment of a lifesaving unmanned aerial vehicle, showing a removable remote control carried by the main body member, and further illustrating the buoyant main body member separated from the frame of the drone, so that a swimmer in distress may use the main body member for flotation while flying the rescue drone via the remote control; 
         FIG.  6    is a side view of an alternate embodiment of a lifesaving unmanned aerial vehicle having a net disposed within the buoyant main body member for carrying a person, and showing a wearable device that is in communication with the rescue drone for purposes of locating a swimmer in distress; 
         FIG.  7    is a perspective view of another alternate embodiment of a lifesaving unmanned aerial vehicle showing an inflatable boat having a frame attached to an upper portion thereof, and further including four propellers that rotate between a horizontal plane and a vertical plane; 
         FIG.  8    is a side view of the alternate embodiment of the lifesaving unmanned aerial vehicle shown in  FIG.  7   , and further illustrating the propellers rotating in a generally horizontal plane; and 
         FIG.  9    is a side view of the alternate embodiment of the lifesaving unmanned aerial vehicle shown in  FIG.  7   , and further illustrating the propellers rotating in a generally vertical plane. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Flying Life Ring 
     The present invention, in a first embodiment, includes a lifesaving unmanned aerial vehicle  10  (also referred to herein as a ‘rescue drone’ or ‘search and rescue drone’) comprising a main body member  12  that is buoyant, and defines a series of vertically oriented holes  14  therein, as shown in  FIGS.  1  and  3    (a ‘flying life ring’ embodiment). Motors  16  and propellers  18  are disposed within the holes  14  of the main body member  12 , which allows the main body member  12  to fly. These embodiments may simply be flown to the location of a swimmer in distress (SID), and may land on the water to serve as a life preserver until the SID can be rescued by a boat, helicopter, or by other means of rescue. Handles  20  may be disposed about the rescue drone  10 , as shown in  FIG.  1   , for purposes of holding onto the drone  10  in the water, and for carrying the drone  10  by hand. 
     A solar powered recharging station may be employed for charging the drone batteries. In a preferred embodiment, the recharging station includes solar panels and/or solar energy collecting devices for capturing solar energy, and further includes a battery. The solar panels are used to keep the battery charged, and the battery charges the drone. Other types of solar chargers are known in the art, and any suitable one may be used. 
     Laser Coordinate Identification Control System 
     In another embodiment, the flying life ring rescue drone  10  (and other embodiments discussed herein) may also include a laser sensor that can detect the distal end of a laser beam from a laser pointer. In other words, if a lifeguard points a laser pointer at a spot where he wishes the flying life ring to land, the laser sensor detects the end of the laser beam reflecting from the target object or spot, and the flying life ring can simply navigate itself to land on that spot. It essentially follows the laser beam, when that mode is activated. 
     In another embodiment, a GPS enabled laser-based range finder  100  (similar to those currently available for golfers, marksmen, and the like) may be used to ‘paint the target’ and determine the exact coordinates at the end of the laser beam. 
     This system allows any personnel with virtually no training to control, launch and deliver the rescue drone to a distressed party in any body of water. The simple to use guidance and control system creates the opportunity for those without pilot experience to launch and direct the rescue drone to the party in need. 
     Using components similar to those found in high end GPS based laser range finders primarily used in golf and marksman applications such as the Bushnell Hybrid Laser Rangefinder + GPS, the responding personnel employ a handheld optical unit. This unit, appearing similar to a Monoscope, or singular telescope, may be used to select the spot where the rescue drone assistance is required. Once the target location is identified, the user pushes an initiation sequence on a button on the optical unit. This initiates a wireless communication between the handheld optical unit and the rescue drone control station, or directly to the rescue drone, itself. In one embodiment, the station incorporates a processing device (small form factor computer such as an IBM NUC) to control the rescue drone and transceiver radio for communications, monitoring and redirection of the rescue drone. The station receives the communication from the handheld optical devices, including specific coordinate information of the target site. The control station automatically creates a mission and uploads the flight information to the rescue drone. Takeoff is initiated and the rescue drone flies to the target site as a predetermined altitude. The rescue drone then descends at a predetermined rate and lands at the target for floatation and continued identification of position. Any time the operator pushed the button again the new coordinate information is uploaded to the rescue drone. 
     The GPS feature allows the laser range finder  100  to know its own location, and the laser range finder may also detect the precise direction in which the laser beam is pointed. Combining that information along with the range or distance to the target location, the system calculates the coordinates of the target location and transmits that information (either directly, or through a separate rescue drone station) to the rescue drone for execution. 
     Such a laser range finder  100  may include a transmitter to communicate with an onboard computer or programmable logic device carried by the rescue drone  10 . Essentially, a lifeguard points the laser of the range finder to the target landing spot in close proximity to a swimmer in distress, and the range finder calculates the GPS coordinates of the target point and transmits that information to the rescue drone, which may autonomously fly to the target spot for landing. This system may refresh itself over very short time intervals, so that the calculations are happening repeatedly, and obviously change as the laser beam moves in real time, so that the rescue drone  10  is constantly being updated with current coordinates for a target spot. Thereby, the rescue drone  10  simply chases the laser dot and lands on the target spot, even if the target spot moves somewhat while the rescue drone  10  is en route to the target spot. One example of a GPS enabled, laser-based range finder is the Hybrid Rangefinder + GPS, manufactured and sold by Bushnell. 
     It should be understood that the rescue drone  10  may be programmed to perform in different ways. For instance, the rescue drone  10  can be programmed to simply fly to the target spot and land, or the rescue drone  10  may be programmed to stop and hover over the spot at a predetermined altitude for a brief time period, or until it receives a ‘land’ command from the user or operator. Other target landing flight and navigation protocols may be developed and programmed, as desired. 
     In use, if a lifeguard sees a swimmer in distress, then he or she may launch the drone, and point the laser pointer at a spot on the water in close proximity to the swimmer in distress. The flying life ring (or any of the other versions of the rescue drone  10  discussed herein) simply follows the laser beam to the spot where the laser beam is pointed, preferably in an autonomous manner. This arrangement allows a floatation device to be delivered very quickly to a swimmer in distress, at precise locations, with an easy-to-use interface - a laser pointer or GPS enabled laser-based range finder. Additionally, such a technique requires very little training for a lifeguard to operate. 
     Alternatively, and particularly on the larger, more sophisticated versions of the search and rescue drone discussed herein, a laser pointer or laser-based range-finder may be mounted on the rescue drone  10  itself, and operated by an operator viewing real-time camera footage from the drone  10 . This feature allows a remote user to simply point the laser where he or she wishes the rescue drone  10  to land, and the drone  10  may navigate itself in the most efficient manner to that spot. 
     Search and Rescue 
     Another embodiment of the present invention is a rescue drone  10  that preferably includes a floating portion  12  (or “main body member”), a frame  42  connected to the floating portion  12 , wherein the frame  42  includes outwardly extending arms, each carrying a motor  16  and propeller  18 , and further including a camera  22 , a transmitter/receiver for receiving flight instructions and transmitting information back to an operator, lights  24  for assistance with rescue operations, and an EPIRB radio beacon  26  for transmitting an SOS call for help along with location coordinates, as shown in  FIGS.  2 A,  2 B,  5  and  6   . Additionally, the rescue drone  10  may further include an onboard computing device for controlling the above-referenced components, either via remote control  60  or autonomously based on installed programming. In this embodiment, the floating portion  12  is preferably positioned on a bottom portion of the drone  10 , and may serve as a flotation device for a swimmer in distress (SID). The lights  24  may include flashing strobe lights of different colors, for attracting the attention of rescuers who are searching for the SID and the drone itself. Additionally, the drone may be equipped with spotlights  24  used during search and rescue operations to illuminate the area that is being searched, or which may be used to illuminate the SID for various purposes. 
     In use, the rescue drone  10  is launched when it has been determined that there is a SID in the area, and the drone  10  may be operated manually by an operator using a remote control device  60  to fly and navigate, or the rescue drone  10  may be used in autonomous mode, so that it is capable of flying itself in a specific search pattern. For manual flight, the rescue drone  10  operates like currently available drones, which may be flown by simple visual operation (watching the drone itself directly), or by viewing the feed from the camera  22  positioned on the drone (as if the drone operator were in a virtual ‘cockpit’ of an aircraft). In the latter case, the operator may use a video screen, goggles, or any other suitable video screen type of component. 
     For autonomous flight, the rescue drone  10  may be programmed to fly and navigate in many different ways. First, the drone  10  may simply be programmed to execute a standard search pattern. Alternatively, if used on a boat or ship, the rescue drone may follow the GPS “breadcrumb trail,” which is essentially the path that the boat or ship has taken up to that point in time, but in the reverse direction, which is particularly useful in man-overboard situations. In this way, the drone itself may be programmed to track the movement of the ship in order to establish the breadcrumb trail, or that information may be transmitted from another GPS device onboard the boat or otherwise. Another option, if multiple drones  10  are used, is to program them to work in concert with one another, so that each drone is programmed to cover a particular area or direction, and so that the drones  10  are not searching the same area as another drone  10 , in order to optimize the amount of area covered as quickly as possible during a search and rescue operation. 
     It is also contemplated that the rescue drone  10  may include infra-red or thermal sensors (which may be part of the camera  22 , or may be separate from the camera  22 ), in order to identify people in the water through their heat signatures. Obviously, a live person in the water will have a higher temperature than the surrounding water, so infra-red or thermal sensors or cameras may be used to help identify SIDs. Another option is to provide the rescue drone  10  with software that recognizes patterns, and also recognizes disruptions in patterns, such the patterns of waves in the water, which are disrupted by a SID. Any of these methods may be used to autonomously identify a SID, which may generate an alert to a human operator, who may then either confirm that the rescue drone  10  has found the SID, or may confirm that the object identified is not a SID, or may take over control of the drone  10  in order to investigate further. Alternatively, the drone  10  may simply be programmed to land near the SID without human intervention, if necessary. 
     Wearable Devices 
     It is also contemplated that the rescue drone  10  may receive a signal, including location information, from a device worn or carried by a person. Such a device could take many forms, including a cell phone, a smart watch (Apple Watch, for instance), a bracelet or necklace, or any other device that includes either an RFID chip or necessary electronics and transmitter for sending a signal to the rescue drone  10 . For these purposes, the transmitter device will be referred to as a transmitter bracelet  50 , as shown in  FIG.  6   , and it should be understood that a transmitter bracelet, for these purposes, encompasses any wearable device that transmits a signal or communicates in any way with the rescue drone to provide a rescue location or coordinates. The transmitter bracelet  50  may be worn by deckhands on a fishing boat, crew and/or passengers on a cruise ship, or others onboard a boat, and may be activated either automatically in a man-overboard situation, or may be activated manually. Activation of the transmitter bracelet  50  preferably alerts the boat captain and crew of the man-overboard situation, and causes the rescue drone  10  to automatically deploy and follow the transmitter bracelet  50  signal to the location of the SID. Alternatively, the rescue drone  10  may be launched manually in such a situation. 
     In one embodiment, the rescue drone  10  mates with a docking base charging station  28  when not in use, or when in ‘standby mode,’ as shown in  FIGS.  2 A and  2 B . The charging station  28  is preferably connected to a power source, and serves as a charger for the rescue drone  10 , so that the rescue drone  10  stays charged and ready to be deployed at all times. In one embodiment, the charging station  28  may be in the shape of a cone (as shown), so that the rescue drone  10  may automatically fly back and land on the charging station  28  without human intervention, although other shapes may be used. The cone shape allows the rescue drone  10  to descend down on top of the charging station  28  so that the round floating portion  12  may be guided by the shape of the cone until the charging surfaces  30  are connected between the drone  10  and the charging station  28 . This arrangement also allows the drone  10  to be deployed directly from the charging station  28  in an emergency, so that the drone  10  simply launches upwardly until it clears the top of the charging station  28  and then begins its search or navigation mission. 
     In use, the rescue drone  10  either searches for a SID, or flies directly to the location of the transmitter bracelet  50 . Upon arrival at the location of the SID, the rescue drone  10  may land close to the SID, so that the SID may use the rescue drone  10  as a flotation device. Additionally, the rescue drone  10  may activate its lights  24  in order to assist rescuers in finding the SID, and may further activate the EPIRB  26 , which sends a distress signal out on an emergency frequency, along with location information. These actions may be automated, or may be taken manually by a human operator. 
     Rescue Drones for Carrying Passengers 
     In another embodiment, the rescue drone  10  includes a basket  32 , harness, or other means for actually recovering a swimmer in distress, and flying that person back to a ship or to shore, as shown in  FIG.  4   . In this embodiment, the drone  10  may either land in the water so that a swimmer in distress may climb aboard, or the drone  10  may lower a basket  32  or harness down to the swimmer while the drone  10  hovers overhead. In either embodiment, the drone  10  may be equipped with a button  36  or other means for indicating that the swimmer is safely aboard the basket  32  or is engaged within the harness, which then triggers the drone  10  to fly the swimmer back to safety. Alternatively, this operation may be carried out manually by a human operator using a remote control device  60 , which may be a dedicated device, a smart phone, a computer, a tablet, or any other suitable remote control device  60 . In this embodiment, the basket  32  or harness may be attached to a cable  38  and winch  40  system, similarly to those deployed on rescue helicopters used by the Coast Guard and the military. 
     For autonomous operation of any embodiment disclosed herein, the rescue drone  10  may include an on-board computing device to execute programmed operations, including navigation and flight, identification of objects in the water, sending and receiving information, landing, activating lights  24  and the EPIRB  26 , and returning to the boat, charging station  28 , or other place of origin. The rescue drone  10  may also record camera footage and/or sensor readings from a full mission, and may transmit that data in real time, or may simply record it for access and download later. In one embodiment, the rescue drone  10  may also carry a remote control (tablet style computing device), or an array including a microphone, speaker, and/or video screen for audio and/or video communications between a human operator (rescuer) and the SID. For instance, the rescue drone  10  may employ a small screen, similar to the screen of a smart phone, allowing a SID to communicate with the drone operator or rescuer (similarly to Apple’s popular FaceTime application), which is useful for allowing the rescuer to ascertain the medical condition of the SID. This arrangement allows the rescuer to be prepared with appropriate medical supplies to deal with the specific issues and ailments that the SID is suffering from. Additionally, in the case of a boat accident or other incident where there may be wreckage, fire, oil floating in the water, or other dangers, the SID can communicate that information through the audio/video transmission components on the rescue drone. 
     Additionally, it is contemplated that the onboard computing device  70 , which may be roughly the size and shape of a smart phone or tablet, may serve as a remote control and be detachable from the drone, so that a SID may use the onboard computing device  70  to operate the rescue drone in the case of a prolonged rescue situation, as shown in  FIG.  5   . For example, if the SID is out of communication range with rescuers for any reason, he or she may detach the onboard computer  70  to launch the drone  10  from the water. The rescue drone  10  may possibly increase its transmission range by ascending to a higher altitude. Additionally, the SID may also be able to view the camera feed from the drone  10  via the onboard computing device/remote control, and if he sees a watercraft in the distance, may send the drone  10  in that direction to establish communication and request assistance. Or, if the SID is in the water at night, he may wish to simply launch the rescue drone  10  and activate the lights  24  while maintaining physical contact with the floating portion  12 , allowing the drone  10  to hover overhead, in order to direct the rescuers to his position in darkness, similarly to launching a flare. In a preferred embodiment, the onboard computer/remote control  70  fits into a cradle that is positioned on the rescue drone, and the cradle is operationally connected to an onboard battery. In this way, the onboard computer  70  may recharge itself when it is positioned within the cradle. 
     The rescue drone  10  may also include solar panels positioned on an upper side thereof, which may be used to charge or recharge the rescue drone battery or batteries. It should be understood that, although different embodiments have been described herein, any of the components and features described in a particular embodiment may be used on or in connection with any other embodiment described herein. 
     In yet another embodiment of the rescue drone  10 , the floating portion  12  (which is used as a flotation device for a SID) may be detachable (either remotely, or manually) from the frame  42  of the rescue drone  10 , so that the rescue drone  10  may either land on water and subsequently separate, if necessary, or so that the floating portion  12  may be detached during flight and dropped to a SID. In this embodiment, as shown in  FIG.  5   , it is contemplated that the EPIRB  26  is attached to the floating portion  12 , in order to direct rescuers to the SID in a scenario where the rescue drone  10  becomes separated from the floating portion  12  and the SID. Further, in this embodiment, the onboard computer/remote control  70  may also be attached to the floating portion  12 , so that the SID is able to operate the rescue drone  10  from the water, if necessary. One advantage to this arrangement is that the SID has a flotation device while the drone  10  is at a higher altitude and serving as a communications relay between rescuers and the SID. In some situations, the SID may be in the water with the floating portion  12 , and the drone  10  may be hovering overhead with lights  24  flashing, transmitting an emergency distress signal, and shining a spotlight  24  down on the SID. 
     Yet another embodiment of the present invention is shown in  FIG.  6   , wherein the floating portion  12  includes a net  80  or other support surface for supporting and carrying a rescued swimmer in distress. In this embodiment, the swimmer in distress simply climbs aboard the rescue drone and sits on the net  80 , and the rescue drone may fly the rescued swimmer to the boat, to shore, or to some other designated safety area. 
     Rescue Drone/Fanboat 
       FIGS.  7 - 9    show another alternate embodiment of a lifesaving unmanned aerial vehicle, a rescue drone/fanboat. In this embodiment, the main body member  12  is preferably in the form of an inflatable watercraft having a floor and a transom, although any suitable boat or buoyant structure may be used. A frame member is attached to the inflatable watercraft, and other electronic components may be attached to the frame, including strobe lights and general purpose lights, a GPS, a transmitter/receiver, and the like. The watercraft may also include a compartment or dry-box for mounting other types of electronics, and/or for storage of survival gear, water, flares, a remote control, or any other types of cargo. Handles or a safety line may be attached at any desirable place on the watercraft or the frame. In a preferred embodiment, a safety line is attached along the sides of the watercraft, as shown in  FIGS.  7 - 9   . 
     The frame also carries pivoting mounts  104  for four propellers  18 , wherein the pivoting mounts  104  are preferably powered for automated rotation. The pivoting mounts  104  may pivot in the range from 90 degrees to 360 degrees, as desired. The pivoting mounts  104  allow the propellers  18  to rotate from a horizontal plane to a vertical plane. This embodiment is designed to take off and land vertically, while the propellers  18  rotate in a generally horizontal plane. The propellers  18  are preferably disposed within a cage  106  or other similar type of device, in order to allow air to pass through efficiently, and also reduce the likelihood of accidents where the propeller  18  might come into violent contact with wreckage, debris, a human extremity, or the like. 
     In use, the search and rescue drone  10  of  FIGS.  7 - 9    launches vertically, flies to a SID, and lands on the water nearby in a vertical manner. After the SID has boarded, and is safely within the watercraft, the propellers  18  rotate by roughly 90 degrees, so that they are pushing air toward the rear of the watercraft or main body member  12 . At this point, the watercraft essentially becomes a fan boat, because the propellers  18  are propelling the watercraft carrying the SID forward by blowing air in a backward direction. This arrangement also allows the search and rescue drone  10  to carry smaller motors for rotating the propellers  18 , when compared to other versions that lift SIDs out of the water and fly them to safety, because the motors are not required to lift the extra weight of a person or people out of the water. 
     It is contemplated that the search and rescue drone/ fanboat  10  may be designed to carry a single passenger or multiple passengers, and this version of the invention may carry or be equipped with any of the other features or components that are discussed elsewhere herein. 
     Any of the above-referenced embodiments may include other features, as well, including a waterproof or water-resistant hatch  44  on the floating portion that opens to reveal a storage compartment  46  that may be used to store rescue supplies, such as water, food, reflective gear, flashlights, an inflatable raft, a survival suit, or any other supplies that may be helpful to a swimmer in distress. Additionally, it should be understood that the motors described herein may be powered by electricity, gasoline, diesel, hydrogen, natural gas, propane, or any other suitable method. 
     Although the present invention has been described in considerable detail with reference to certain preferred versions thereof, other versions are possible. Therefore, the spirit and scope of the appended claims should not be limited to the description of the preferred versions contained herein. All features disclosed in this specification may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise. Thus, unless expressly stated otherwise, each feature disclosed is one example only of a generic series of equivalent or similar features.