Abstract:
An unmanned aerial vehicle apparatus comprises a frame. Further, the unmanned aerial vehicle apparatus comprises a propulsion mechanism coupled to the frame that propels the frame through the air. In addition, the unmanned aerial vehicle apparatus comprises a storage device that stores one or more airbags and is coupled to the frame. The unmanned aerial vehicle apparatus also comprises an inflation device coupled to the frame that receives an activation signal and inflates the one or more airbags based upon receipt of the activation signal to deploy the one or more airbags from the storage device prior to an impact of the frame with an object.

Description:
BACKGROUND 
       [0001]    1. Field 
         [0002]    This disclosure generally relates to the field of aerial vehicles. More particularly, the disclosure relates to safety mechanisms for aerial vehicles. 
         [0003]    2. General Background 
         [0004]    Unmanned aerial vehicles (“UAVs”) such as flying robots, drones, airplanes, helicopters, multicopters, e.g., flying robots that operate in a manner similar to helicopters with multiple propellers, balloons, etc. have become more commonplace in entertainment environments such as theme parks, film sets, sports environments, and news environments. A pilot can wirelessly navigate the UAV from a remote location. Alternatively, the UAV may have an autopilot feature so that it is operated and navigated by a computing device. A human is not present on the UAV during flight of the UAV. UAVs have been used for providing entertainment, aerial cinematography, gathering video, images, and/or audio, etc. 
         [0005]    As UAVs increasingly fly over locations where people are present, safety for those people is an important goal. Equipment malfunction, aerial hazards, and aerial maneuvers are examples of events which may result in a loss of propulsion. 
         [0006]    A previous solution was to attach a parachute to the UAV. The parachute could be ejected via a wireless instruction sent by a pilot or a computing device that operated the UAV or by on-board monitoring systems. A problem with using a parachute is that the parachute can get tangled with propulsion units of the UAV during or after ejection of the parachute. Typical UAVs, e.g. multicopters, are devices that are naturally unstable, hence malfunctions can result in a tumbling vehicle. For example, a multicopter can flip during ejection of the parachute. The parachute could then get entangled with the propulsion units of the multicopter during the flip and not eject properly or not provide much help in decelerating the multicopter if the parachute is ejected. Further, a parachute is often fabricated from a heavy material that significantly slows normal movement. Moreover, a parachute requires a fall distance to deploy and properly decelerate a vehicle. Therefore, a parachute is less effective at low altitude. As a result, a continuing need exists for robust UAV safety systems that do not impede normal operation and that perform well at low altitudes. 
         [0007]    Another solution was the establishment of a geofence. The geofence allows the UAV to fly within a perimeter, e.g., a safe distance away from people or objects. Geofencing restricts the use and benefits of a UAV. Since a geofence is a control system rather than a physical barrier, the UAV can still fly through the geofence as a result of hardware or logic failure. 
         [0008]    There is a continuous need to improve safety performance of UAVs. 
       SUMMARY 
       [0009]    An unmanned aerial vehicle apparatus comprises a frame and a propulsion mechanism coupled to the frame that propels the frame through the air. A storage device stores one or more airbags and is coupled to the frame. An inflation device coupled to the frame receives an activation signal and in response inflates the one or more airbags prior to an impact of the frame with an object. 
         [0010]    A method comprises propelling an unmanned aerial vehicle through the air. An activation signal is sent to an inflation device that inflates one or more airbags coupled to the aerial vehicle to deploy the one or more airbags from the storage device. 
         [0011]    A system comprises a sensor that determines a condition of a component of an unmanned aerial vehicle. The unmanned aerial vehicle has one or more airbags and an inflation device. Further, the system comprises a processor that receives a signal from the sensor indicative of the condition of the component and sends an activation signal to the inflation device to deploy the one or more airbags from the storage device prior to an impact of the unmanned aerial vehicle with an object. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0012]    The above-mentioned features of the present disclosure will become more apparent with reference to the following description taken in conjunction with the accompanying drawings wherein like reference numerals denote like elements and in which: 
           [0013]      FIG. 1  illustrates a UAV system. 
           [0014]      FIGS. 2A, 2B, and 2C  illustrate a front view, a side view, and a perspective view of the components of the UAV apparatus illustrated in  FIG. 1 . 
           [0015]      FIGS. 3A and 3B  illustrate an example of the UAV apparatus illustrated in  FIGS. 2A, 2B, and 2C  partially deploying and fully deploying a first airbag and a second airbag. 
           [0016]      FIG. 4  illustrates the internal electronic components of the electronic control device illustrated in  FIGS. 2A, 2B, and 2C . 
       
    
    
     DETAILED DESCRIPTION 
       [0017]    A UAV comprising an impact absorption device is provided to improve safety in close proximity to a flying UAV. The impact absorption device is inflated by the UAV after detection of a condition that may lead to a ground impact, but prior to that impact. The inflated impact absorption device covers the hard, sharp, and spinning parts of the UAV, e.g., the propellers, the frame, etc. As a result, any impact of the UAV is with an inflated object rather than a hard or spinning UAV component. The impact absorption device is configured to prioritize reducing the effect of impact as opposed to preventing damage to the UAV. 
         [0018]    As an example, the impact absorption device comprises one or more airbags that are each activated by one or more components of the UAV after the UAV detects a condition warranting activation. Such conditions include power failure, motor failure, guidance system failure, unexpected change in control source, navigation failure, air pressure change, change in acceleration or speed, mid-air collision with an obstacle and the like. For instance, a first airbag is positioned above the center of gravity of the UAV whereas a second airbag is positioned below the center of gravity of the UAV. Each airbag has dimensions such that both in total engulf the entire frame structure and propulsion mechanism, e.g., propellers, of the UAV. In contrast with previous approaches, e.g., the parachute configuration, that allowed different components of the UAV to be exposed after the safety mechanism was activated, the UAV uses the impact absorption device to engulf the hard, sharp and spinning components of the UAV to reduce the effect of impact. 
         [0019]    The impact absorption device also helps slow the acceleration of the UAV during free fall. For instance, the UAV engulfed in two airbags will have significantly greater air resistance and so fall at a much slower velocity and acceleration than the UAV without two airbags. The resulting slower descent lowers the force of impact arising from contact with objects or the ground. 
         [0020]    The impact absorption device is configured to lessen effects on flight performance in contrast with previous approaches, e.g., the parachute configuration, that used heavy materials that affected flight performance of a UAV. For example, each airbag can weigh less than one hundred grams. The airbag can be fabricated from an ultra lightweight film rather than a durable and puncture-proof material commonly used for parachutes. Therefore, the UAV can fly at similar speeds and perform similar maneuvers with the impact absorption device as if the UAV did not have the impact absorption device. 
         [0021]      FIG. 1  illustrates a UAV system  100 . The UAV system  100  comprises a UAV  102 , e.g., a flying robot, drone, unmanned airplane, unmanned helicopter, unmanned multicopter, unmanned balloon, and a remote control  104  having a transmitter  106 . The UAV  102  flies autonomously or with remote human navigation above one or more people  108  and/or a plurality of objects (not shown). The remote control  104  is a wireless device that radiates Radio Frequency (“RF”), audio, or an optical signal to activate the impact absorption device. The signal can be generated by a human operator or autonomously via a computing device. The computing device can be an onboard device that executes instructions for the UAV. Alternatively, the computing device can be a remote land-based device that sends remote instructions to the UAV from an operator. The computing device can also be present onboard a neighboring or remotely situated distinct UAV. The instructions can go to a particular location in 3D space. If the UAV  102  flies autonomously, the UAV system  100  may operate without the remote control  104 . 
         [0022]      FIGS. 2A, 2B, and 2C  illustrate a front view, a side view, and a perspective view of the components of the UAV apparatus  102  illustrated in  FIG. 1 . The UAV apparatus  102  has a frame  205 , a plurality of connectors  206  and  208 , a plurality of storage devices  207  and  209 , and a plurality of inflation devices  210  and  211 . The connectors  206  and  208  can be platforms, chambers, arms, cages, or other types of mounting devices, that are used to connect the plurality of storage devices  207  and  209  to the frame  205 . The first storage device  207  is operably attached to the first inflation device  210 . Further, the second storage device  209  is operably attached to the second inflation device  211 . 
         [0023]    The inflation devices  210  and  211  can be canisters of a compressed gas such as carbon dioxide. The inflation devices  210  and  211  are used to inflate impact absorption devices such as an airbag stored in the first storage device  207  and an airbag stored in the second storage device  209 . Although the inflation devices  210  and  211  are illustrated as being positioned within the connectors  206  and  208 , e.g., chambers, the inflation devices  210  and  211  can be situated on the top or sides of the storage devices  207  and  209 . Alternatively, the inflation devices  210  and  211  can be positioned on the connectors  206  and  208  in proximity to the first storage device  207  and the second storage device  209 . In addition, the first inflation devices  210  and  211  can take the form of a variety of different shapes and sizes. The inflation devices  210  and  211  can also be integrated within the first storage device  207  and the second storage device  209 . 
         [0024]    The frame  205  also has the components of the UAV that are used to perform flight operation of the UAV. For instance, the frame  205  has a control device  201  that has the components for performing flight operation either autonomously or based upon an instruction received from the remote control  104 . The control device  201  also has sensors for detecting a UAV malfunction or other event in which the airbag should be deployed and one or more electromechanical actuators, e.g., valves, for activating the impact absorption device. 
         [0025]    The frame  205  also has a plurality of arms  202  that are each operably connected to a propulsion mechanism  203 , e.g., a propeller mounted on a motor, where the motor is coupled to control device  201 . Control device  201  varies the speed of each of the propulsion devices  203  so as to control altitude and travel direction of UAV  102 . Other implementations may be operated with one propeller, e.g., a helicopter, or without any propellers, e.g., a balloon. 
         [0026]    Further, a mounting device  212  may be used to mount various components to the frame  205 . For example, an image capture device  213  may be mounted to the frame  205 . The image capture device  213  may perform image capture during flight to allow a remotely positioned human pilot to navigate the UAV  102 . 
         [0027]      FIGS. 3A and 3B  illustrate an example of the UAV apparatus  102  illustrated in  FIGS. 2A, 2B, and 2C  partially deploying and fully deploying a first airbag and a second airbag. The first airbag  302  is deployed from the first storage device  207  by the first inflation device  210  whereas the second airbag  304  is deployed from the second storage device  209  by the second inflation device  211 . The first airbag  302  has dimensions such that the first airbag  302  covers the propellers  203  attached to the frame  205 , the first storage device  207 , and a significant portion of the electronic control device  201 . Further, the second airbag  304  has dimensions such that the second airbag  304  covers the second storage device  209 , the mounting device  212 , the image capture device  213 , and a significant portion of the electronic control device  201 . The first airbag  302  and the second airbag  304  cover all of the propellers  203 , electronic components, and any other components that are part of or are attached to the frame  205  that may present hard, sharp or spinning components during free fall or impact. The airbags  302  and  304  together form a balloon-like structure. As the balloon-like structure is inflated it has a solid shape that absorbs large forces associated with rapid deceleration of UAV  102  upon impact. The inflation can be performed at various speeds, e.g., instantaneously, slowly, etc. 
         [0028]    Although two inflation devices  210  and  211  are illustrated, a single inflation device may be used to inflate multiple airbags such as airbags  302  and  304 . For instance, a single inflation device, e.g., a valve, may be electromechanically operated by the electronic control device  201  to rotate to different storage devices  207  and  209  to inflate airbags  302  and  304 . 
         [0029]    Further, a single airbag may be used if a portion of the UAV  102  has a soft payload. For instance, a UAV  102  that has a bottom portion with a soft material may only need a single airbag to cover an upper portion having sharp and other components that pose safety hazards. In addition, more than two airbags may be used to cover a UAV apparatus  102 . For example, a large UAV  102  may have many components that necessitate use of more than two airbags. 
         [0030]    In one implementation, the airbags  302  and  304  are sealed. In other words, the airbags  302  and  304  do not release air upon impact unless there are punctures of the airbags  302  and  304 . In another implementation, the airbags  302  and  304  have vents that release air from the airbags  302  and  304  upon impact. The release of air upon impact helps further reduce forces resulting from impact. 
         [0031]      FIG. 4  illustrates the internal components of the control device  201  illustrated in  FIGS. 2A, 2B, and 2C . The electronic control device  201  comprises a processor  401 , a memory  402 , a sensor  403 , and an activator  404 . The sensor(s)  403 , e.g., accelerometer, altimeter, gyroscope, etc., provides data, e.g., an activation signal, to the processor  401  so that the processor  401  can determine if the UAV apparatus  102  has malfunctioned or otherwise experienced an event that warrants deploying airbags. 
         [0032]    A variety of different sensors  403  can be used to trigger an activation signal, which removes power from the propulsion devices, e.g., propellers  203  and/or activates the electromechanical activator  404 . The sensors  403  can detect the malfunction based on simplified logic criteria, i.e., sense a flip, a broken propeller, bad battery, electronic health failure, communication failure, or software failure. 
         [0033]    As an example, the sensor  403  is an accelerometer that provides acceleration data to the processor  401  for storage in the memory  402 . Alternatively, the acceleration data can be stored in one or more registers of the processor  401 . The processor  401  then determines that the UAV apparatus  102  is accelerating faster than a predetermined acceleration. The processor  401  then determines that airbags  302  and  304  illustrated in  FIGS. 3A and 3B  should be deployed. The processor  401  sends an activation signal to the electromechanical activator  404  instructing the electromechanical activator  404  to activate inflation devices  210  and  211 . The inflation devices  210  and  211  then deploy airbags  302  and  304  from the first storage device  207  and the second storage device  209 . 
         [0034]    As another example, the sensor  403  is an altimeter that determines altitude data for the UAV apparatus  102 . The processor  401  then determines that the UAV apparatus  102  is flying at an altitude that is less than a predetermined altitude. The processor  401  then determines that airbags  302  and  304  illustrated in  FIGS. 3A and 3B  should be deployed. 
         [0035]    As yet another example, the sensor  403  is a gyroscope that determines pitch, roll, and/or yaw data. The gyroscope provides that data to the processor  401 , which can determine if the UAV is performing any unexpected rotations. As an example, the gyroscope sends the processor  401  data that indicates that the UAV had a pitch and roll each greater than seventy degrees. The processor  401  determines that such a rotation is a flip that was unexpected. 
         [0036]    As another example, the sensor  403  is a current sensing sensor that determines if a motor (not shown) is consuming current. If the sensor  403  determines that the motor is not consuming any current or is consuming an abnormally high amount of current, the sensor  403  provides that data to the processor  401 , which may determine that a motor failure has occurred. 
         [0037]    The sensor  403  may also be a component sensor, i.e., a sensor that determines that a component has malfunctioned. For instance, the sensor  403  may determine that a propeller  203  is not functioning properly. The sensor  403  sends the data to the processor  401  so that the processor  401  can determine if airbag deployment is necessary based upon whether or not the sensor data is within an acceptable threshold or range. The sensor  403  can also determine if a communication failure has occurred with a particular component. 
         [0038]    The processor  404  is not necessary for operation of the sensor  403 . For example, a component attached to the sensor  403  can be configured to operate only if the sensor  403  provides a signal having a value in a certain range. For instance, the inflation devices  210  and  211  illustrated in  FIGS. 2A, 2B, and 2C  may be operably attached to a sensor that detects if the motor is not consuming any current or is consuming an abnormally high amount of current. The inflation devices  210  and  211  are configured to be activated to inflate airbags if the sensor  403  does not provide any signal indicating current consumption or provides a signal of an abnormally high level of current.