Methods and computing devices for controlling an aircraft and/or a vehicle to enable retrieval of the aircraft at the vehicle

Apparatus and methods for controlling an aircraft and/or a vehicle are described. A vehicle speed and direction are received. A wind-over-vehicle speed and direction of wind at the vehicle are measured. An aircraft ground speed and direction are received. An aircraft-relative-to-vehicle speed and an aircraft-relative-to-vehicle direction are calculated based on the aircraft ground speed and direction and the wind-over-vehicle speed and direction. A wind-over-vehicle envelope is calculated based on system design limits for retrieving the aircraft at the vehicle. The wind-over-vehicle envelope maps limits of wind-over-vehicle speeds over a range of directions that enable retrieval of the aircraft at the vehicle. The aircraft and/or the vehicle are controlled using the wind-over-vehicle envelope, the aircraft-relative-to-vehicle speed, and/or the aircraft-relative-to-vehicle direction.

FIELD

The present disclosure generally relates to vehicle and aircraft navigation, and more particularly to methods and apparatus related to controlling an aircraft and/or a vehicle to enable retrieval of the aircraft at the vehicle.

BACKGROUND

Guidance, navigation, and control systems for aircraft include avionics on the aircraft and associated support systems. Guidance of the aircraft during aircraft takeoff, landing, and/or retrieval can be affected by wind and weather conditions, aircraft weight, aircraft payload, mission characteristics, and perhaps other conditions. Further, guidance of the aircraft during takeoff, landing, and/or retrieval at a vehicle, such as a ship or truck, can be complicated by vehicle-related conditions. Current techniques for addressing the complexity of guidance of the aircraft during takeoff, landing, and/or retrieval at a vehicle relate to the use of conservative guidelines at these times. Use of such conservative guidelines can make aircraft takeoff, landing, and/or retrieval unnecessarily difficult, particularly for small aircraft. What is needed are more accurate guidance techniques for guiding (small) aircraft at takeoff, landing, and/or retrieval, particularly when the aircraft take off, land, and/or are retrieved at a vehicle.

SUMMARY

In one example, a method for controlling an aircraft and/or a vehicle to enable retrieval of the aircraft at the vehicle is described. A vehicle speed of the vehicle and a vehicle direction of the vehicle are received. A wind-over-vehicle speed of wind at the vehicle and a wind-over-vehicle direction of wind at the vehicle are measured. An aircraft ground speed of the aircraft and an aircraft ground direction of the aircraft are received. An aircraft-relative-to-vehicle speed and an aircraft-relative-to-vehicle direction are calculated based on the aircraft ground speed, the aircraft ground direction, the wind-over-vehicle speed, and the wind-over-vehicle direction. One or more aircraft retrieval system design limits related to retrieving the aircraft at the vehicle are determined. A wind-over-vehicle envelope is calculated based on the one or more aircraft retrieval system design limits, the wind-over-vehicle envelope mapping limits of wind-over-vehicle speeds over a range of directions that enable retrieval of the aircraft at the vehicle. The aircraft and/or the vehicle are controlled to enable retrieval of the aircraft at the vehicle using the wind-over-vehicle envelope, the aircraft-relative-to-vehicle speed, and the aircraft-relative-to-vehicle direction.

In another example, a computing device is described. The computing device includes one or more processors and one or more non-transitory computer-readable media configured to store at least computer-readable instructions that, when executed by the one or more processors, causes the computing device to perform functions. The functions include: receiving a vehicle speed of the vehicle and a vehicle direction of the vehicle; measuring a wind-over-vehicle speed of wind at the vehicle and a wind-over-vehicle direction of wind at the vehicle; receiving an aircraft ground speed of the aircraft and an aircraft ground direction of the aircraft; calculating an aircraft-relative-to-vehicle speed and an aircraft-relative-to-vehicle direction based on the aircraft ground speed, the aircraft ground direction, the wind-over-vehicle speed, and the wind-over-vehicle direction; accounting for one or more aircraft retrieval system design limits related to retrieving the aircraft at the vehicle; calculating a wind-over-vehicle envelope based on the one or more aircraft retrieval system design limits, the wind-over-vehicle envelope mapping limits of wind-over-vehicle speeds over a range of directions that enable retrieval of the aircraft at the vehicle; and controlling the aircraft and/or the vehicle to enable retrieval of the aircraft at the vehicle using the wind-over-vehicle envelope, the aircraft-relative-to-vehicle speed, and the aircraft-relative-to-vehicle direction.

In still another example, a non-transitory computer readable medium is described. The non-transitory computer readable medium has stored thereon computer-readable instructions, that when executed by one or more processors of a computing device, cause the computing device to perform functions. The functions include: receiving a vehicle speed of the vehicle and a vehicle direction of the vehicle; measuring a wind-over-vehicle speed of wind at the vehicle and a wind-over-vehicle direction of wind at the vehicle; receiving an aircraft ground speed of the aircraft and an aircraft ground direction of the aircraft; calculating an aircraft-relative-to-vehicle speed and an aircraft-relative-to-vehicle direction based on the aircraft ground speed, the aircraft ground direction, the wind-over-vehicle speed, and the wind-over-vehicle direction; accounting for one or more aircraft retrieval system design limits related to retrieving the aircraft at the vehicle; calculating a wind-over-vehicle envelope based on the one or more aircraft retrieval system design limits, the wind-over-vehicle envelope mapping limits of wind-over-vehicle speeds over a range of directions that enable retrieval of the aircraft at the vehicle; and controlling the aircraft and/or the vehicle to enable retrieval of the aircraft at the vehicle using the wind-over-vehicle envelope, the aircraft-relative-to-vehicle speed, and the aircraft-relative-to-vehicle direction.

DETAILED DESCRIPTION

Herein described are methods and apparatus related to guiding an aircraft and/or a vehicle on an approach path for landing and/or otherwise retrieving the aircraft at the vehicle. In some examples, the vehicle can be in motion at when the aircraft is landing and/or being retrieved. The vehicle can be a ship, motor vehicle, another aircraft, and/or another mobile device. In some examples, the herein-described methods and apparatus can be used for guiding the aircraft and/or the vehicle during aircraft take off and/or during other navigational maneuvers.

The herein-described methods and apparatus can utilize a computing device. The computing device can receive and/or otherwise determine navigational data about the vehicle and/or the aircraft; e.g., vehicle navigational data such as a speed of the vehicle and/or a direction of travel of the vehicle, aircraft navigational data such as a ground speed of the aircraft and/or a ground direction of travel of the aircraft. The computing device can measure and/or otherwise determine wind speed and wind direction at the vehicle; e.g., the wind speed and wind direction can be measured at the vehicle (such as with an anemometer or other wind gauge) and resulting wind speed and wind direction data can be provided to the computing device. The computing device can calculate and/or otherwise determine a “wind-over-vehicle” direction based on the vehicle direction and the wind direction, where the wind-over-vehicle direction is a direction of wind adjusted for the vehicle's direction. The computing device can also calculate and/or otherwise determine a wind-over-vehicle speed based on the vehicle speed and the wind speed, where the wind-over-vehicle speed is a speed of wind adjusted for the vehicle's speed. For example, the wind-over-vehicle direction and/or speed can be a wind direction and/or speed at the vehicle relative to the vehicle's direction and/or speed.

The computing device can calculate and/or otherwise determine an aircraft-relative-to-vehicle direction and an aircraft-relative-to-vehicle speed based on the aircraft ground direction, the wind-over-vehicle direction, the aircraft ground speed, and the wind-over-vehicle speed, where the aircraft-relative-to-vehicle direction and aircraft-relative-to-vehicle speed respectively indicate the direction and speed of the aircraft's travel relative to the vehicle's direction and speed of travel. Then, a “crab angle”, which is an angle between the aircraft ground direction and the aircraft-relative-to-vehicle direction, can be calculated and/or otherwise determined.

The computing device can receive, determine, and/or otherwise account for one or more aircraft retrieval system design limits related to retrieving the aircraft at the vehicle. Then, the computing device can calculate and/or otherwise determine a wind-over-vehicle envelope based on the one or more aircraft retrieval system design limits, where the wind-over-vehicle envelope can map limits of wind-over-vehicle speeds over a range of directions that enable retrieval of the aircraft at the vehicle. The wind-over-vehicle envelope can be displayed by the computing device; e.g., for an operator of the aircraft.

Then, the aircraft and/or the vehicle can be controlled to enable retrieval of the aircraft at the vehicle using the wind-over-vehicle envelope, the aircraft-relative-to-vehicle speed, and the aircraft-relative-to-vehicle direction. For example, the speed and direction of the aircraft can be adjusted to allow the aircraft to land or otherwise be retrieved at the vehicle based on the wind-over-vehicle envelope. As another example, an optimal approach speed for the aircraft can be calculated, perhaps based on a pre-defined approach angle for the aircraft. In yet another example, directions to control the vehicle can be provided using the wind-over-vehicle envelope.

Vector summation representations and associated algorithms can be used to determine the wind-over-vehicle envelope. For example, vectors that are based on speed and direction can be used; e.g., a wind velocity vector that is based on the wind speed and wind direction; an aircraft velocity vector that is based on the aircraft ground speed and the aircraft ground direction; a vehicle velocity vector that is based on the vehicle speed and vehicle direction.

The resulting wind-over-vehicle envelope can indicate maximum wind-over-vehicle speeds over a range of wind-over-vehicle directions. The wind-over-vehicle envelope can be used in aircraft approach and departure procedures, while taking vehicle conditions, aircraft conditions, environmental conditions, recovery and launch equipment limitations, and/or other conditions into account. Vehicle conditions can include, but are not limited to, vehicle direction, vehicle speed, vehicle course, and/or conditions on the vehicle imposed by a mission (e.g., the vehicle has to be at a pre-defined location at a pre-defined time as part of the mission). Aircraft conditions can include, but are not limited to, aircraft configuration, aircraft weight, aircraft ground speed, aircraft ground direction, crab angle, approach angle between the aircraft and the vehicle, minimum aircraft airspeed, maximum aircraft airspeed, and/or conditions on the vehicle imposed by a mission (e.g., the aircraft has to land on the vehicle at or before a pre-defined time as part of the mission). Environmental conditions include, but are not limited to, wind conditions (e.g., wind direction and speed), air temperature, and/or other environmental conditions (e.g., sea state, river state, terrain conditions, obstacles present in the environment, altitude). Recovery and launch equipment conditions include but are not limited to, minimum and/or maximum aircraft recovery speeds, minimum and/or maximum aircraft launch speeds, ranges of feasible directions for aircraft recovery based on recovery equipment and/or vehicle conditions, and/or ranges of feasible directions for aircraft launch based on recovery equipment. Other conditions can include, but are not limited to, other mission-based conditions, fuel/energy limitations on the vehicle and/or aircraft, and/or additional other weather conditions (e.g., a direction and/or speed of an oncoming storm; daylight or night-time hours, humidity, barometric pressure, dew point).

The computing device can use an algorithm for computing the wind-over-vehicle envelope. The algorithm can receive and/or otherwise determine, input conditions such as inputs related to vehicle conditions, aircraft conditions, environmental conditions, recovery and launch equipment limitations, and/or other conditions. The algorithm can use these input conditions to generate a wind-over-vehicle envelope that maps the input conditions as limitations of wind-over-vehicle speeds and directions. The algorithm can proceed by outputting the wind-over-vehicle envelope for display using a graphical user interface (GUI), commands for controlling the aircraft and/or the vehicle based on the wind-over-vehicle envelope, recommendations and/or other information for controlling the aircraft and/or the vehicle based on the wind-over-vehicle envelope. Then, perhaps after an operator decision, the algorithm can loop back to receiving and/or otherwise determining the input conditions in order to re-compute the wind-over-vehicle envelope.

The wind-over-vehicle envelope can provide an aircraft operator aboard the vehicle with an easy to interpret takeoff and landing diagram combining multiple limitations, reducing a number of pre-flight or pre-landing check list items. That is, the wind-over-vehicle envelope can transform complex aircraft and launch and recovery equipment design limitations into an easy to interpret diagram. The use of the wind-over-vehicle envelope can therefore beneficially reduce time to flight readiness, reduce operator workload during aircraft recovery, and reduce complexity of aircraft and/or vehicle launch and recovery considerations for the operator.

Using the wind-over-vehicle envelope can save time when landing and/or retrieving aircraft and can provide more accurate and, in some cases, less conservative guidance for aircraft and vehicle control. Providing less conservative guidance advantageously can enable aircraft to take off, land, and/or be retrieved under conditions considered to be unsuitable under more conservative guidance, thereby increasing mission readiness and mission success. Further, use of a simple, easily readable wind-over-vehicle envelope can save time and effort for an operator of the aircraft and/or a related vehicle during takeoff, landing, and/or retrieval of the aircraft.

FIG. 1is a flowchart of method100for controlling an aircraft and/or a vehicle to enable retrieval of the aircraft at the vehicle, according to an example embodiment. Method100is executable by a computing device, such as computing device200described below in the context ofFIG. 2.

Method100begins at block110ofFIG. 1, where the computing device can receive a vehicle speed of the vehicle and a vehicle direction of the vehicle, such as discussed herein in the context at least ofFIGS. 4 and 5.

At block120, the computing device can measure a wind-over-vehicle speed of wind at the vehicle and a wind-over-vehicle direction of wind at the vehicle, such as discussed herein in the context at least ofFIGS. 4, 5, and 7.

At block130, the computing device can receive an aircraft ground speed of the aircraft and an aircraft ground direction of the aircraft, such as discussed herein in the context at least ofFIGS. 4 and 6.

At block140, the computing device can calculate an aircraft-relative-to-vehicle speed and an aircraft-relative-to-vehicle direction based on the aircraft ground speed, the aircraft ground direction, the wind-over-vehicle speed, and the wind-over-vehicle direction, such as discussed herein in the context at least ofFIGS. 4 and 5.

At block150, the computing device can account for one or more aircraft retrieval system design limits related to retrieving the aircraft at the vehicle, such as discussed herein in the context at least ofFIGS. 6 and 7.

At block160, the computing device can calculate a wind-over-vehicle envelope based on the one or more aircraft retrieval system design limits, the wind-over-vehicle envelope mapping limits of wind-over-vehicle speeds over a range of directions that enable retrieval of the aircraft at the vehicle, such as discussed herein in the context at least ofFIGS. 4, 6, and 7.

At block170, the computing device can control the aircraft and/or the vehicle to enable retrieval of the aircraft at the vehicle using the wind-over-vehicle envelope, the aircraft-relative-to-vehicle speed, and the aircraft-relative-to-vehicle direction, such as discussed herein in the context at least ofFIGS. 3A, 3B, 6, 7, 11, and 13. In some examples, the vehicle can include an aircraft retrieval system; then, controlling the aircraft and/or the vehicle to enable retrieval of the aircraft at the vehicle can include controlling the aircraft and/or the vehicle to enable retrieval of the aircraft at the vehicle using the aircraft retrieval system, such as discussed herein in the context at least ofFIGS. 3A and 3B. In some of these examples, controlling the aircraft and/or the vehicle to enable retrieval of the aircraft at the vehicle using the aircraft retrieval system can include: directing the aircraft to fly towards the aircraft-relative-to-vehicle direction and near the aircraft-relative-to-vehicle speed until reaching the vehicle; and when the aircraft reaches the vehicle, retrieving the aircraft using the aircraft retrieval system, such as discussed herein in the context at least ofFIGS. 3A and 3B. In other of these examples, the aircraft retrieval system can include an elongated member and/or a net; then, retrieving the aircraft using the aircraft retrieval system can include retrieving the aircraft using the elongated member and/or the net of the aircraft retrieval system, such as discussed herein in the context at least ofFIGS. 3A and 3B. In even other of these examples, the aircraft can include a hook; then, retrieving the aircraft using the elongated member and/or the net of the aircraft retrieval system includes retrieving the aircraft using the elongated member and/or the net of the aircraft retrieval system and the hook, such as discussed herein in the context at least ofFIGS. 3A and 3B.

In other examples, controlling the aircraft and/or the vehicle to enable retrieval of the aircraft at the vehicle can include: controlling the aircraft ground speed of the aircraft and/or the aircraft ground direction of the aircraft; and/or controlling the vehicle speed of the vehicle and/or the vehicle direction of the vehicle, such as discussed herein in the context at least ofFIGS. 6, 7, 11, and 13. In even other examples, controlling the aircraft and/or the vehicle to enable retrieval of the aircraft at the vehicle can include: determining a minimum wind-over-vehicle speed and a maximum wind-over-vehicle speed at the aircraft-relative-to-vehicle direction using the wind-over-vehicle envelope; determining whether the wind-over-vehicle speed is between the minimum wind-over-vehicle speed and the maximum wind-over-vehicle speed; and after determining that the wind-over-vehicle speed is between the minimum wind-over-vehicle speed and the maximum wind-over-vehicle speed, maintaining the aircraft-relative-to-vehicle speed and the aircraft-relative-to-vehicle direction of the aircraft, such as discussed herein in the context at least ofFIGS. 6, 7, and 12.

In still other examples, controlling the aircraft and/or the vehicle to enable retrieval of the aircraft at the vehicle can include: determining a minimum wind-over-vehicle speed and a maximum wind-over-vehicle speed at the aircraft-relative-to-vehicle direction using the wind-over-vehicle envelope; determining whether the wind-over-vehicle speed is not between the minimum wind-over-vehicle speed and the maximum wind-over-vehicle speed; and after determining that the wind-over-vehicle speed is not between the minimum wind-over-vehicle speed and the maximum wind-over-vehicle speed, providing a command to the aircraft that changes the aircraft-relative-to-vehicle speed of the aircraft and/or the aircraft-relative-to-vehicle direction of the aircraft, such as discussed herein in the context at least ofFIGS. 6, 7, and 13. In yet other examples, controlling the aircraft and/or the vehicle to enable retrieval of the aircraft at the vehicle can include: determining a minimum wind-over-vehicle speed and a maximum wind-over-vehicle speed at the aircraft-relative-to-vehicle direction using the wind-over-vehicle envelope; determining whether the wind-over-vehicle speed is between the minimum wind-over-vehicle speed and the maximum wind-over-vehicle speed; and after determining that the wind-over-vehicle speed is between the minimum wind-over-vehicle speed and the maximum wind-over-vehicle speed, maintaining the vehicle speed and the vehicle direction of the vehicle, such as discussed herein in the context at least ofFIGS. 6, 7, and 12.

In further other examples, controlling the aircraft and/or the vehicle to enable retrieval of the aircraft at the vehicle can include: determining a minimum wind-over-vehicle speed and a maximum wind-over-vehicle speed at the aircraft-relative-to-vehicle direction using the wind-over-vehicle envelope; determining whether the wind-over-vehicle speed is not between the minimum wind-over-vehicle speed and the maximum wind-over-vehicle speed; and after determining that the wind-over-vehicle speed is not between the minimum wind-over-vehicle speed and the maximum wind-over-vehicle speed, changing the vehicle speed of the vehicle and the vehicle direction of the vehicle, such as discussed herein in the context at least ofFIGS. 6, 7, and11.

In some examples, method100can further include: providing an output of a computing device, the output including one or more of: an image of the wind-over-vehicle envelope, an image of a crab angle plot of crab angles and wind-over-vehicle directions, or an image of a closure rate plot of a closure rate between the aircraft and the vehicle, such as discussed herein in the context at least ofFIGS. 4-13.

In other examples, method100can further include: utilizing the vehicle on a body of water, such as discussed herein in the context at least ofFIGS. 3A and 3B. In even other examples, method100can further include: utilizing the vehicle on a road, such as discussed herein in the context at least ofFIGS. 3A and 3B.

FIG. 2is a block diagram of computing device200, according to an example embodiment. Computing device200includes one or more user interface components201, network-communication interface module202, one or more processors203, data storage204, and sensor(s)210, all of which may be linked together via a system bus, network, or other connection mechanism205, in accordance with an example embodiment. In particular, computing device200can perform some or all of the herein-described functionality related to one or more of: methods100,500,600,700, vehicle310,350, aircraft320, diagrams400,800,900,1000, scenario1100, user interface1110, a computing device, an aircraft, a vehicle, a wind-over-vehicle envelope, a crab angle plot, and/or a closure rate plot. In some embodiments, computing device200can be a mobile or non-mobile computing device, and can be embodied as one or more of: desktop computer, laptop or notebook computer, personal data assistant (PDA), mobile phone, smart phone, smart watch, embedded processor, and/or any similar device that is equipped with at least one processing unit capable of executing machine-language instructions that implement at least part of the herein-described techniques and methods.

User interface component(s)201can include one or more components that can receive input and/or provide output, perhaps to a user. User interface component(s)201can include one or more components configured to send and/or receive data to and/or from a user and/or other entities; such components can include but are not limited to: a keyboard, a keypad, a touch screen, a touch pad, a computer mouse, a track ball, a joystick, a game controller, button and/or other similar devices configured to receive user input from a user of and/or other entities associated with the computing device200. User interface component(s)201can include one or more components configured to display visual outputs; such components can include but are not limited to: but are not limited to: cathode ray tubes (CRTs), liquid crystal displays (LCDs), light emitting diodes (LEDs), displays using digital light processing (DLP) technology, printers, light bulbs, and/or other devices capable of displaying visual outputs (e.g., graphical, textual, and/or numerical information). User interface component(s)201can also include one or more components to generate audible output(s); such components can include but are not limited to: a speaker, speaker jack, audio output port, audio output device, earphones, and/or other similar devices configured to generate audible output(s) and/or convey sound and/or audible information; e.g., to a user of computing device200.

Network-communication interface module202can be configured to send and receive data over one or more wireless interfaces207and/or one or more wired interfaces208via a data or other communications network. Wireless interface(s)207, if present, can utilize an air interface, such as a Bluetooth®, ZigBee®, Wi-Fi™, and/or WiMAX™ interface to a data network, such as a wide area network (WAN), a local area network (LAN), one or more public data networks (e.g., the Internet), one or more private data networks, or any combination of public and private data networks. Wired interface(s)208, if present, can comprise a wire, cable, fiber-optic link and/or similar physical connection to a data network, such as a WAN, a LAN, one or more public data networks, such as the Internet, one or more private data networks, or any combination of such networks.

In some embodiments, network-communication interface module202can be configured to provide reliable, secured, and/or authenticated communications. For each communication described herein, information for ensuring reliable communications (i.e., guaranteed message delivery) can be provided, perhaps as part of a message header and/or footer (e.g., packet/message sequencing information, encapsulation header(s) and/or footer(s), size/time information, and transmission verification information such as cyclic redundancy check (CRC) and/or parity check values). Communications can be made secure (e.g., be encoded or encrypted) and/or decrypted/decoded using one or more cryptographic protocols and/or algorithms, such as, but not limited to, Data Encryption Standard (DES), Advanced Encryption Standard (AES), an Rivest-Shamir-Adelman (RSA) algorithm, a Diffie-Hellman algorithm, a secure sockets protocol such as Secure Sockets Layer (SSL) or Transport Layer Security (TLS), and/or Digital Signature Algorithm (DSA). Other cryptographic protocols and/or algorithms can be used as well or in addition to those listed herein to secure (and then decrypt/decode) communications.

Processor(s)203includes one or more central processing units, computer processors, mobile processors, digital signal processors (DSPs), graphics processing units (GPUs), microprocessors, computer chips, programmable processors, multi-core processors, and/or other processing units configured to execute machine-language instructions and process data. Processor(s)203can be configured to execute computer-readable program instructions206that are contained in data storage204and/or other instructions as described herein.

Data storage204includes one or more physical and/or non-transitory storage devices, such as read-only memory (ROM), random access memory (RAM), removable disk drives, hard drives, thumb drives, magnetic-tape memory, optical-disk memory, flash memory, volatile storage devices, non-volatile storage devices, and/or other storage devices. Generally, a storage device is hardware that is capable of storing information; for example, data, computer-readable program instructions, and/or other suitable information on a temporary basis and/or a permanent basis. Data storage204can include one or more physical and/or non-transitory storage devices with at least enough combined storage capacity to contain computer-readable program instructions206and any associated/related data structures. In some embodiments, some or all of data storage204can be removable, such as a removable hard drive, removable disk, or flash memory.

Computer-readable program instructions206and any data structures contained in data storage204include computer-readable program instructions executable by processor(s)203and any storage required, respectively, to perform at least part of the herein-described functionality of a computing device. For example, data storage204can also store data used to perform at least part of the herein-described functionality of a computing device. Computer-readable program instructions206can include instructions that when executed by processor(s)203to perform functions, including but not limited to herein-described functionality of software, displays, and/or user interfaces.

In some embodiments, computing device200includes one or more sensors210. Sensor(s)210can be configured to measure conditions in an environment around computing device200and provide data about the measured conditions of the environment. The data can include, but are not limited to: meteorological conditions including, but not limited to, wind speed, wind direction, temperature, humidity, barometric pressure, and/or rainfall; location data about computing device200including, but not limited to, latitude, longitude, and/or altitude data; kinematic information (e.g., location, speed, velocity, acceleration data) related to computing device200, one or more vehicles, and/or one or more aircraft, and electromagnetic radiation data (e.g., infra-red, ultra-violet, X-ray data). The one or more sensors210can include, but are not limited to, one or more: Global Positioning System (GPS) sensors, location sensors, gyroscopes, accelerometers, magnetometers, video and/or still cameras, light sensors, infrared sensors, ultraviolet sensors, X-ray sensors, meteorological sensors, proximity sensors, vibration and/or motion sensors, heat sensors, thermometers, lasers, wind sensors, barometers, rain gauges, and microphones. Other examples of sensor(s)210are possible as well.

In some examples, sensors210can be utilized for relative position sensing, where relative position sensing provides information about aircraft velocity relative to a vehicle; e.g., using differential GPS and/or radio-based triangulation methods. In particular of these examples computing device200and sensors210can provide and use relative position sensing in order to automate features related to aircraft guidance, vehicle guidance, and/or aircraft retrieval.

Other components shown inFIG. 2can be varied from the illustrative examples shown. Generally, the different embodiments can be implemented using any hardware device or system capable of running program code.

FIG. 3Adepicts aircraft retrieval on a body of water, according to an example embodiment. In particular,FIG. 3Adepicts vehicle310on body of water312; e.g., vehicle310is a ship, boat, or another other vehicle that can travel on body of water312with aircraft retrieval system330. Vehicle310includes aircraft retrieval system330that can be used to retrieve an aircraft, such as aircraft320, from the air, thereby effectively landing aircraft320at vehicle310. In some examples, aircraft320can be an unmanned aircraft; e.g., an unmanned aerial vehicle (UAV) or drone.

FIG. 3Ashows that aircraft320can include hook322and aircraft retrieval system330can include elongated member332supported between an upper support334and a lower support336. In the example shown inFIG. 3A, elongated member332is a rope—in other examples, elongated member332can be a flexible pole or other similar member.

In the example shown inFIG. 3A, aircraft320has been retrieved at vehicle310by catching hook322in elongated member332. In particular, aircraft320can be controlled to fly on a course so that aircraft320catches onto elongated member332of aircraft retrieval system330; e.g., by catching hook322with elongated member332. Once aircraft320is caught by aircraft retrieval system330, aircraft320can be powered down, removed from aircraft retrieval system330, and placed on vehicle310, thereby landing aircraft320at vehicle310.

FIG. 3Bdepicts aircraft retrieval on a road, according to an example embodiment. In particular,FIG. 3Bdepicts vehicle350on road352; e.g., vehicle350is a truck or other motor vehicle that can travel on road352with aircraft retrieval system330. In some cases, vehicle350travels off-road with aircraft retrieval system330. Vehicle350includes aircraft retrieval system340that can be used to retrieve an aircraft, such as aircraft320, from the air, thereby effectively landing aircraft320at vehicle350.FIG. 3Bshows that aircraft retrieval system340is similar to aircraft retrieval system330ofFIG. 3A. However, where supports334and336of aircraft retrieval system330support elongated member332, corresponding supports344and346of aircraft retrieval system330support net342.

In the example shown inFIG. 3B, aircraft320has been retrieved at vehicle350by catching hook322in net342. In particular, aircraft320can be controlled to fly on a course so that net342of aircraft retrieval system340catches aircraft320; e.g., by catching hook322in net342. Once aircraft320is caught by aircraft retrieval system340, aircraft320can be powered down, removed from aircraft retrieval system340, and placed on vehicle310, thereby landing aircraft320at vehicle350.

In some examples, aircraft retrieval system330is mounted on a land-based vehicle, such as vehicle350; and/or aircraft retrieval system340is mounted on a water-based vehicle, such as vehicle310. In other examples, aircraft retrieval system330and/or aircraft retrieval system340can be mounted on an air-based vehicle, such as an aircraft or other aerial platform that is larger than aircraft320. In other examples, aircraft retrieval system330and/or aircraft retrieval system340are located at a fixed location; e.g., on the ground.

In other examples, aircraft retrieval can be performed using variations of the retrieval techniques discussed in the context of aircraft retrieval systems330and340. For example, hook322can be a “tail hook” mounted at a rear or “tail” portion of aircraft320, and retrieval of aircraft320can involve capture of aircraft320by catching the tail hook using a vertical elongated member such as elongated member332or using a horizontal elongated member; e.g., a rope or wire stretched across a deck, flat bed, or other surface of vehicle310or vehicle350. As another example, net342can be mounted horizontally, rather than vertically, as shown inFIG. 3B. As such, the aircraft can then fly into the horizontally-mounted net, perhaps after or at the same time as powering down. Other variations for performing aircraft retrieval using aircraft retrieval systems330and340are possible as well.

FIG. 4shows diagram400with wind-over-vehicle envelope430associated with aircraft410and vehicle420, according to an example embodiment. Table 1, which is partially reproduced as a Legend inFIG. 4below provides information about the depicted wind-over-vehicle envelope and related vectors.

A computing device at vehicle420can receive or otherwise determine information about vehicle speed and vehicle direction of vehicle420at a time T to form vector VV. For example, VV(and other vectors described herein) can be expressed using polar notation, where the magnitude of VVis the vehicle speed and the angle of VVis the vehicle direction. The computing device can then measure; e.g., using a wind sensor, or otherwise determine information about a wind-over-vehicle speed and a wind-over-vehicle direction of wind at vehicle420at time T and then use the wind-over-vehicle speed and the wind-over-vehicle direction to form vector WoV1. Then, the computing device can determine a vector VWrepresenting wind velocity by performing vector subtraction; that is, VW=WoV1−VV.

The computing device can receive or otherwise determine information about aircraft ground speed and aircraft ground direction of aircraft410at a time T to form vector Vgrepresenting aircraft ground velocity. For example, the computing device and/or other devices on vehicle420can be used to control aircraft410by specifying aircraft ground speed, aircraft ground direction, and/or vector Vgat time T and communicating a command to aircraft410to fly according to the specified aircraft ground speed, aircraft ground direction, and/or vector Vato aircraft410. As another example, information about aircraft ground speed and aircraft ground direction can be provided by GPS and/or relative position sensing. As another example, aircraft410can send information that includes aircraft ground speed and aircraft ground direction to the computing device; then, the computing device can form vector Vgusing the received aircraft ground speed and aircraft ground direction.

In some cases, the computing device can receive or otherwise determine information about aircraft air speed and aircraft air direction of aircraft410at a time T to form vector Varepresenting aircraft air velocity. The computing device can then use vectors Vaand WoV1to form vector Vr. For example, the computing device can have sensors or other devices that measure air speed and air direction of aircraft410. As another example, aircraft410can send information that includes aircraft air speed and aircraft air direction to the computing device; then, the computing device can form vector Vausing the received aircraft ground speed and aircraft ground direction. Then, the computing device can use vector Vato determine vector Vrby performing vector addition; that is, Vr=Va+WoV1.

In some examples, computing device can determine vector Vrrepresenting motion of aircraft410relative to vehicle420using vectors Vgand VV. For example, Vrcan be determined by performing vector subtraction; that is, Vr=Vg−VV.

The computing device can also calculate a scalar crab angle ρ as a difference in directions between vectors Vaand Vr. Further, the computing device can also calculate a scalar approach angle γ as the difference in directions between vectors Vgand Vr.

Wind-over-vehicle envelope430represents ranges of minimum and maximum wind-over-vehicle speeds and directions where aircraft410can be safely retrieved and/or landed on vehicle420; i.e., using aircraft retrieval system330or aircraft retrieval system340. For example,FIG. 4shows that vector VoW1touches wind-over-vehicle envelope430. As vector VoW1touches wind-over-vehicle envelope430, vector VoW1represents a maximum wind-over-vehicle velocity for retrieving and/or landing aircraft410on vehicle420. If vector VoW1extended outside of wind-over-vehicle envelope430, then the corresponding wind-over-vehicle would be too high to safely retrieve and/or land aircraft410on vehicle420. If vector VoW1ended within wind-over-vehicle envelope430, then the corresponding wind-over-vehicle would allow safe retrieval and/or landing of aircraft410on vehicle420.

In particular, vector VoW1touches wind-over-vehicle envelope430at a point corresponding to maximum wind-over-vehicle432. Maximum wind-over-vehicle432represents a maximum wind-over-vehicle speed of approximately 9 meters per second (m/s) at an aircraft approach direction of approximately 307 degrees. As vector VoW1represents a wind-over-vehicle speed of approximately 9 meters per second at an aircraft approach direction of approximately 307 degrees at time T, wind-over-vehicle envelope430and vector VoW1indicate that aircraft410can be safely retrieved and/or landed at vehicle420under conditions prevailing at vehicle420at time T.

FIG. 5is a flowchart of method500related to providing an output, such as a display, based on crab angle ρ and/or a relative speed of an aircraft with respect to a vehicle Vrgiven wind-over-vehicle information, vehicle velocity information, and approach angle information, vehicle v according to an example embodiment. Method500is executable by a computing device, such as computing device200described above in the context ofFIG. 2.

Method500begins at block510, where the computing device can receive VWoV, ψWoV, V_VEH, and ψ_VEH, where:VWoVis a wind-over-vehicle speed of wind over a vehicle; e.g., wind speed as measured at the vehicle,ψWoVis a wind-over-vehicle angle or direction of the wind over the vehicle; e.g., wind angle or direction as measured at the vehicle,V_VEH is a speed of the vehicle, andψ_VEH is a heading or direction of the vehicle.

For example, VWoVand ψWoVcan be collectively considered as wind-over-vehicle information, and V_VEH and ψ_VEH can be collectively considered vehicle velocity information.

At block520, the computing device can receive γ, which is a designated approach angle of an aircraft to the vehicle. For example, γ can be considered as approach angle information.

At block530, the computing device can calculate and/or determine α, which is a wind-over-vehicle angle adjusted by the designated approach angle, using Equation (1):
α=ψWoV−γ  (1)

At block540, the computing device can calculate and/or determine ρ, which is an aircraft crab angle relative to the vehicle, using Equation (2):
ρ=sin−1(VWoV*sin(α))  (2)

At block550, the computing device can calculate and/or determine AH, which is an aircraft heading angle, using Equation (3):
AH=γ−ρ(3)

At block560, the computing device can calculate and/or determine β, which is an aircraft heading angle adjusted by the wind-over-vehicle angle, using Equation (4):
β=π+AH−ψWoV(4)

At block570, the computing device can calculate and/or determine Vr, which is a relative speed of the aircraft with respect to the vehicle, using Equation (5):
Vr=√{square root over ((VWoV2−2*VWoV*cos(β)+1))}  (5)

At block580, the computing device can generate an output based on the relative speed of the aircraft with respect to the vehicle Vrand/or the aircraft crab angle relative to the vehicle ρ. For example outputs, the computing device can display and/or otherwise present: Vrand/or ρ in alphanumeric form, a wind-over-vehicle envelope that has been determined using Vrand/or ρ, a user interface that includes Vr, ρ, and/or information derived from Vrand/or ρ. Other outputs are possible as well.

FIG. 6is a flowchart of method600, which is related to providing mapped data using a user interface, according to an example embodiment. Method600is executable by a computing device, such as computing device200described above in the context ofFIG. 2.

Method600begins at block610, where the computing device can receive data AOC, where AOC stands for aircraft operating conditions. Data AOC can include, but is not limited to, data about: an aircraft, aircraft operating conditions, aircraft operating limitations, and/or aircraft configuration; e.g., aircraft320. For example, data AOC can include data about: aircraft dimensions, maximum and/or minimum aircraft weight, maximum and/or minimum speed, aircraft ceiling information, aircraft engine information, ranges of operating air speeds and/or approach angles for the aircraft, information about aircraft retrieval/landing equipment, aircraft configuration information, aircraft, meteorological and/or other environment information for an environment where the aircraft is operating, aircraft payload, aircraft sensors, aircraft fueling and/or battery information, and/or aircraft communication information.

At block620, the computing device can receive data EC, where EC stands for environmental conditions. Data EC can include, but is not limited to, data: about: wind including a wind over a vehicle, vehicle course and speed, air state, sea state, and/or meteorological and/or other environment information for an environment. In some examples, some or all of data EC about environmental conditions can also, or instead, be provided as data AOC mentioned above with regards to block610; e.g., meteorological and/or other environment information for an environment where an aircraft is operating.

At block630, the computing device can receive data ARS, where ARS stands for aircraft retrieval system. Data ARS can be about one or more design limits about one or more aircraft retrieval systems; e.g., aircraft retrieval system340. Data ARS can include, but is not limited to data about: one or more configurations of the one or more aircraft retrieval systems, dimensions about the one or more aircraft retrieval systems, and/or maximum and/or minimum aircraft speed and/or other information at a time of aircraft retrieval by the aircraft retrieval system(s). In some examples, some or all of data ARS about environmental conditions can also, or instead, be provided as data AOC mentioned above with regards to block610; e.g., information about the aircraft's configuration relates to the aircraft retrieval system(s), maximum and/or minimum aircraft acceleration, velocity, altitude, and/or speed information at the time of aircraft retrieval by the aircraft retrieval system(s).

At block640, the computing device can map data AOC, EC, and/or ARS to a wind-over-vehicle envelope relative to vehicle orientation (course and/or speed). For example, the computing device can use method500to calculate values used in mapping AOC, EC, and/or

ARS to the wind-over-vehicle envelope. In some examples, the computing device can use the maximum and/or minimum aircraft acceleration, velocity, altitude, and/or speed information at the time of aircraft retrieval by the aircraft retrieval system(s) in data ARS, the aircraft, aircraft operating limitations, and/or aircraft configuration information in data AOC, and the wind-over-vehicle data: in data EC to determine the wind-over-vehicle envelope.

In other examples, the computing device can use a loop to iterate over a range of possible vehicle-approach directions; e.g., a range of possible vehicle-approach directions from 0 degrees to 360 degrees. For each iteration of the loop involving a particular vehicle-approach direction of the range of possible vehicle-approach directions, the computing device can determine minimum and/or maximum wind-over-vehicle speeds that allow for retrieval of an aircraft approaching a vehicle at the particular vehicle-approach direction based on the data AOC, EC, and/or ARS. Then, the computing device can generate the wind-over-vehicle envelope as a graph of the minimum and/or maximum wind-over-vehicle speeds plotted at the particular vehicle-approach direction, thereby creating a graph of the wind-over-vehicle envelope that represents minimum and/or maximum wind-over-vehicle speeds over the range of possible vehicle-approach directions.

At block650, the computing device can display mapped data using a user interface (UI), such as but not limited to a user interface related to aircraft and/or vehicle operations. A user interface related to aircraft and/or vehicle operations is also discussed herein at least in the context ofFIGS. 7, 11, 12, and 13.

At block660, the computing device can receive an input I from the user interface. The input I can be one or more of: an input for controlling and/or operating an aircraft, an input for controlling and/or operating a vehicle, an input related to updating and/or otherwise changing a display of the user interface, an input related to accepting or rejecting a recommendation provided by the user interface, an input related to exiting method600, and/or another input.

At block670, the computing device can determine whether input I relates to exiting method600. For example, an input related to exiting method600can be generated by: pressing or otherwise selecting an Exit button or similar user interface control, pressing or otherwise selecting one or more keys, and/or providing a command related to exiting method600. If the computing device determines that input I relates to exiting method600, then the computing device can proceed to block680. Otherwise, the computing device determines that input I does not relate to exiting method600and can proceed to block690.

At block680, the computing device can exit method600.

At block690, the computing device can update AOC, EC, and/or ARS based on input I and/or sensor data After completing the updates to AOC, EC, and/or ARS based on input I and/or sensor data, the computing device can proceed to block640.

FIG. 7is a flowchart of method700, which is related to providing a wind-over-vehicle envelope using a user interface, according to an example embodiment. Method700is executable by a computing device, such as computing device200described above in the context ofFIG. 2.

Method700begins at block710, where the computing device can receive information related to VWoV, ψWoV, γ, CAS, and ARS where:VWoVis a wind-over-vehicle speed of wind over a vehicle; e.g., wind speed as measured at the vehicle,ψWoVis a wind-over-vehicle angle or direction of the wind over the vehicle; e.g., wind angle or direction as measured at the vehicle,γ is a designated approach angle of an aircraft to the vehicle,CAS is a commanded airspeed of the aircraft, andARS includes data about aircraft retrieval system design limits.

Data ARS is discussed above in the context of at least block630of method600. In some examples, at block710, the computing device can receive additional information as well; e.g., some or all of data AOC and/or data EC discussed in the context of at least blocks610and620of method600.

At block720, the computing device can determine CrabMax, CrabMin, VrMax, and VrMin using the data about aircraft retrieval system design limits ARS, whereCrabMax and CrabMin are respective maximum and minimum crab angles for the aircraft relative to the vehicle, andVrMax and VrMin are respective maximum and minimum speeds of the aircraft relative to the vehicle.
For example, the computing device can use the maximum and/or minimum aircraft acceleration, velocity, altitude, and/or speed information at the time of aircraft retrieval by the aircraft retrieval system(s) in data ARS to determine CrabMax, CrabMin, VrMax, and VrMin.

At block730, the computing device can determine the relative speed of the aircraft with respect to the vehicle Vrand/or the aircraft crab angle relative to the vehicle ρ. For example, the computing device can use method500to determine Vrand/or ρ.

At block740, the computing device can map a wind-over-vehicle envelope relative to vehicle orientation (i.e., vehicle orientation can include the vehicle direction and/or the vehicle speed) using VWoV, ψWoV, γ, CAS, Vr, ρ, CrabMax, CrabMin, VrMax, and/or VrMin. The computing device can determine the wind-over-vehicle envelope using method600, and then apply VWoV, ψWoV, γ, CAS, Vr, ρ, CrabMax, CrabMin, VrMax, and/or VrMin to the wind-over-vehicle envelope to determine one or more recommendations RECS. The recommendation(s) RECS can include, but are not limited to, recommendations to maintain or change vehicle speed, controlling the aircraft ground speed of the aircraft and/or the aircraft ground direction of the aircraft; controlling the vehicle speed of the vehicle and/or the vehicle direction of the vehicle, maintaining a speed and/or a direction of the aircraft and/or the vehicle, changing a speed and/or a direction of the aircraft and/or the vehicle, recommendations related to vehicle direction, aircraft speed, and/or aircraft direction based on the wind-over-vehicle envelope, VWoV, ψWoV, γ, CAS, Vr, ρ, CrabMax, CrabMin, VrMax, and/or VrMin. For example, RECS can include recommendations related to: controlling the aircraft and/or the vehicle to enable retrieval of the aircraft at the vehicle using an aircraft retrieval system described by data ARS, retrieving the aircraft using the aircraft retrieval system.

At block750, the computing device can display WoV envelope and/or RECS using a user interface, such as but not limited to a user interface related to aircraft and/or vehicle operations. A user interface related to aircraft and/or vehicle operations is also discussed herein at least in the context ofFIGS. 6, 11, 12, and 13.

In some examples, some or all of recommendations RECS can be associated with one or more commands that the computing device can send to the aircraft, vehicle, and/or the aircraft retrieval system to carry out the associated recommendations. For example, a recommendation R1to change an aircraft ground speed, airspeed, ground direction, and/or air direction can be associated with one or more commands C1to the aircraft to make the recommended change(s) in speed and/or direction. Then, a user of the user interface related to aircraft and/or vehicle operations can use the user interface to review recommendation R1and indicate acceptance of the recommendation R1—upon the indication of the acceptance of recommendation R1, the computing device can send command(s) C1to the aircraft to make the recommended change(s) in speed and/or direction. Other examples of recommendations and related commands are possible as well.

At block760, the computing device can receive an input I from the user interface. Examples of input I are discussed above in the context of block660of method600.

At block770, the computing device can determine whether input I relates to exiting method700. Example inputs related to exiting a method are described above in the context of block670of method600. If the computing device determines that input I relates to exiting method700, then the computing device can proceed to block780. Otherwise, the computing device determines that input I does not relate to exiting method700and can proceed to block790.

At block780, the computing device can exit method700.

At block790, the computing device can update VWoV, ψWoV, γ, CAS, and/or ARS based on input I and/or sensor data After completing the updates to VWoV, ψWoV, γ, CAS, and/or ARS based on input I and/or sensor data, the computing device can proceed to block740.

FIG. 8illustrates diagram800showing wind-over-vehicle envelope810with related crab angle plot820and related closure rate plot830, according to an example embodiment. Diagram800illustrates an example aircraft approach toward vehicle840, where Table 2 summarizes conditions related to the example aircraft approach example and where Table 2 is partially reproduced inFIG. 8.

TABLE 2Sym-bolMeaningExample ValueVVVelocity of vehicle 8405 meters per second in a directionshown as 0 degrees in FIG. 8WoVWind-over-vehicle for10 meters per second maximum with avehicle 8401 meter per second tail wind limit;wind- over-vehicle direction asindicated.VaAir velocity of an aircraftAircraft air speed is 30 meters perapproaching vehicle 840second; aircraft air directionunspecifiedNo crab angle limitsNone.No closure rate limitsNone.

Diagram800illustrates that wind-over-vehicle envelope810indicates relationships between a direction of a vehicle-relative approach path with respect to vehicle840measured in degrees and a wind-over-vehicle speed measured in meters per second. Wind-over-vehicle envelope810indicates maxima and minima of wind-over-vehicle speed at a given vehicle-relative approach path direction for an aircraft approaching vehicle840that allows for successful retrieval of the aircraft. For example, suppose an aircraft is approaching vehicle840using an approach path having vehicle-relative approach path direction of approximately 15 degrees—this approach path is illustrated at an upper portion ofFIG. 8using an arrow passing through both vehicle840and wind-over-vehicle envelope810. Then, wind-over-vehicle envelope810illustrates that a minimum wind-over-vehicle speed allowing successful retrieval of the aircraft at the approximately 15 degree approach path is 0 meters per second and a maximum wind-over-vehicle speed allowing successful retrieval of the aircraft at the approximately 15 degree approach path is approximately 9 meters per second.

FIG. 8shows crab angle plot820and closure rate plot830for the example mentioned above with respect to Table 2. Crab angle plot820, shown at lower left ofFIG. 8, shows relative crab angles for the aircraft approaching vehicle840with respect to possible wind-over-vehicle directions. As examples, circles822,824,826of crab angle plot show respective relative crab angles of approximately −20 degrees, approximately 0 degrees, and approximately +19 degrees, for an aircraft approaching vehicle840with at respective wind-over-vehicle directions of approximately 100 degrees, approximately 200 degrees, and approximately 300 degrees.

Closure rate plot830, shown at lower right ofFIG. 8, shows closure rates, or rates of approach of an aircraft toward vehicle840, with respect to wind-over-vehicle directions. For example, for a wind-over-vehicle direction of 0 degrees in the example mentioned above with respect to Table 2, closure rate plot830indicates that the aircraft will have a closure rate with vehicle840of approximately 18 meters per second. As another example, for a wind-over-vehicle direction of 195 degrees in the example mentioned above with respect to Table 2, closure rate plot830indicates that the aircraft will have a closure rate with vehicle840of approximately 31 meters per second.

FIG. 9illustrates diagram900showing crab angle plot910, related wind-over-vehicle envelope920, and related closure rate plot930, according to an example embodiment. Diagram900illustrates an example aircraft approach toward vehicle840, where Table 3 summarizes conditions related to the example aircraft approach example and is partially reproduced inFIG. 9.

TABLE 3Sym-bolMeaningExample ValueVVVelocity of vehicle 8405 meters per second in a directionshown as 0 degrees in FIG. 9WoVWind-over-vehicle for10 meters per second maximum withvehicle 840a 1 meter per second tail windlimit; wind- over-vehicle directionas indicatedVaAir velocity of an aircraftAircraft air speed is 30 meters perapproaching vehicle 840second; aircraft air directionunspecifiedA minimum crab angle isNone.limited to −10 degreesNo closure rate limitsNone.

The example aircraft approach summarized in Table 3 and shown inFIG. 9is similar to the example aircraft approach summarized in Table 2 and shown inFIG. 8. The difference between the two example aircraft approaches is that the example aircraft approach illustrated by Table 2 andFIG. 8has no limits on crab angles, where the example aircraft approach illustrated by Table 3 andFIG. 9has a crab angle limit where a minimum crab angle is limited to −10 degrees.

As can be seen at upper left ofFIG. 9, crab angle plot910graphically illustrates the crab angle limit where the minimum crab angle is limited to −10 degrees, most notably in limit region912. In comparison to crab angle plot820ofFIG. 8that depicts a minimum crab angle of approximately −20 degrees; e.g., at a wind-over-vehicle angle of approximately 100 degrees, crab angle plot910ofFIG. 9shows a minimum crab angle of approximately −10 degrees; e.g., as shown throughout limit region912.

FIG. 9also shows that limiting the minimum crab angle to −10 degrees has a visible effect not only on crab angle plot910, but also has visible effects on wind-over-vehicle envelope920and closure rate plot930.FIG. 9shows, at lower center, wind-over-vehicle envelope920with limit region922indicating a truncated wind-over-vehicle envelope920for an approximate range of wind-over-vehicle directions of 45 degrees to 105 degrees in comparison to wind-over-vehicle envelope810ofFIG. 8. That is, wind-over-vehicle envelope810shows larger maxima of wind-over-vehicle speeds for vehicle-relative approach path directions between approximately 45 degrees and 105 degrees in comparison to maxima illustrated in limit region922of wind-over-vehicle envelope920. As such, a comparison of wind-over-vehicle envelope810and wind-over-vehicle envelope920illustrates the crab angle limit imposed for the example illustrated by Table 3 andFIG. 9, imposes a corresponding limit on wind-over-vehicle speeds over a range of vehicle-relative approach path directions.

FIG. 9also shows, at upper right, closure rate plot930with limit region932indicating a region where a closure rate of an aircraft approaching vehicle940has been reduced due to the crab angle limit imposed for the example. More particularly, limit region932of closure rate plot930shows a closure rate throughout limit region932of approximately 18 meters per second, while a closure rate of a corresponding region of closure rate plot830increases from approximately 18 meters per second to approximately 20 meters per second as wind-over-vehicle directions ranges from approximately 15 degrees to approximately 45 degrees.

FIG. 10illustrates diagram1000showing crab angle plot1010, related closure rate plot1020, and related wind-over-vehicle envelope1030, according to an example embodiment. Diagram1000illustrates an example aircraft approach toward vehicle840, where Table 4 summarizes conditions related to the example aircraft approach example and is partially reproduced inFIG. 10.

TABLE 4Sym-bolMeaningExample ValueVVVelocity of vehicle 8405 meters per second in a directionshown as 0 degrees in FIG. 10WoVWind-over-vehicle for10 meters per second maximum withvehicle 840a 1 meter per second tail windlimit; wind-over-vehicle directionas indicated.VaAir velocity of an aircraftAircraft air speed is 30 meters perapproaching vehicle 840second; aircraft air directionunspecifiedA minimum crab angle isNone.limited to −10 degreesand a maximum crab angleis limited to +20 degrees.A minimum closure rate isNone.limited to 20 meters persecond.

The example aircraft approach summarized in Table 4 and shown inFIG. 10is similar to the example aircraft approach summarized in Table 3 and shown inFIG. 9. The difference between the example aircraft approach illustrated by Table 3 andFIG. 9has a crab angle limit where a minimum crab angle is limited to −10 degrees and no limits on closure rates, while the example aircraft approach illustrated by Table 4 andFIG. 10has limits on both the minimum crab angle (limited to −10 degrees) and a maximum crab angle limit of +20 degrees, and has a minimum closure rate limit of 20 meters per second.

As can be seen at upper left ofFIG. 10, crab angle plot1010graphically illustrates crab angle limits where the minimum crab angle is limited to −10 degrees, notably in limit region1012and where the maximum crab angle is limited to +20 degrees, notably in limit region1014. In comparison to crab angle plot820ofFIG. 8that depicts a minimum crab angle of approximately −20 degrees; e.g., at a wind-over-vehicle angle of approximately 100 degrees, crab angle plot1010ofFIG. 10shows a minimum crab angle of approximately −10 degrees; e.g., as shown throughout limit region1012. This minimum crab angle limit also leads to effect on envelope1040that truncates wind-over-vehicle envelope1030for an approximate range of vehicle-relative approach path directions of 45 degrees to 105 degrees in comparison to wind-over-vehicle envelope810ofFIG. 8, where wind-over-vehicle envelope1030is shown at lower center ofFIG. 10.

Also, in comparison to crab angle plot820ofFIG. 8that depicts a maximum crab angle of approximately +21 degrees; e.g., at a wind-over-vehicle angle of approximately 295 degrees, crab angle plot1010ofFIG. 10shows a maximum crab angle of approximately +20 degrees; e.g., as shown throughout limit region1014. This maximum crab angle limit also leads to effect on envelope1042that truncates wind-over-vehicle envelope1030for an approximate range of vehicle-relative approach path directions of 280 degrees to 320 degrees in comparison to wind-over-vehicle envelope810ofFIG. 8.

FIG. 10shows that the minimum closure rate limit of 20 meters has an effect both closure rate plot1020and wind-over-vehicle envelope1030. As shown at upper right ofFIG. 10, closure rate plot1020includes limit region1022where the closure rate is shown as being at least 20 meters per second throughout a range of wind-over-vehicle directions between approximately 320 degrees to approximately 45 degrees. The minimum closure rate limit of 20 meters also has effect1044on wind-over-vehicle envelope1030of reducing a maximum wind-over-vehicle speed throughout the range of vehicle-relative approach path directions between approximately 320 degrees to approximately 45 degrees from the approximately 10 meters per second shown throughout the range of vehicle-relative approach path directions between approximately 320 degrees to approximately 45 degrees shown in wind-over-vehicle envelope810ofFIG. 8.

FIGS. 11, 12, and 13illustrate scenario1100utilizing user interface1110related to aircraft and/or vehicle operations, according to an example embodiment. Scenario1100begins with a computing device providing user interface1110to display a wind-over-vehicle envelope for retrieving an aircraft at a vehicle and recommendations related to controlling the vehicle to enable a safe retrieval of the aircraft. Scenario1100continues with the recommendations being accepted and user interface1110updating the display of the wind-over-vehicle envelope being updated to indicate that the aircraft's approach to the vehicle is within the wind-over-vehicle envelope and therefore represents a safe approach to the vehicle for aircraft retrieval. Scenario1100continues with a control of user interface1110being selected to change display of the wind-over-vehicle envelope to a display of a closure rate plot for the aircraft. Along with the display of the closure rate plot, user interface1110displays recommendations to change the airspeed and air direction of the aircraft. The recommendations to change the airspeed and air direction of the aircraft are accepted and scenario1100ends.

FIG. 11shows that scenario1100begins with a computing device providing user interface1110. User interface1110includes display region1112and current vehicle/wind/aircraft data region1140.FIG. 11shows that display region1112includes graph1120, display closure rate plot control1124, and display crab angle plot control1126. Graph1120includes wind-over-vehicle envelope1122, current position1130illustrated using a black star, and recommended position1132illustrated using a white star. Wind-over-vehicle envelope1122shows ranges of wind-over-vehicle speeds that allow for safe retrieval of the aircraft at the vehicle using the aircraft retrieval system plotted with respect to a range of wind-over-vehicle directions represented in graph1122as 0 degrees to 360 degrees. Current position1130illustrates how prevailing conditions for the aircraft, the vehicle, and the wind relate to wind-over-vehicle envelope1122.

FIG. 11shows that current position1130is outside of wind-over-vehicle envelope1122and therefore retrieval of the aircraft under the prevailing conditions may not be successful and/or safe. Graph1120also includes recommended position1132inside wind-over-vehicle envelope1122, where recommended position1132indicates a set of conditions for the aircraft, the vehicle, and the wind where retrieval of the aircraft is likely to be safe and successful.

Display closure rate plot control1124, when selected (e.g., by a user of user interface1110), instructs user interface1110to display a closure rate plot, such as a closure rate plot discussed above at least in the context ofFIGS. 8, 9, and 10. Display crab angle plot control1126, when selected, instructs user interface1110to display a crab angle plot, such as a crab angle plot discussed above at least in the context ofFIGS. 8, 9, and 10.

Current vehicle/wind/aircraft data region1140includes data about the prevailing conditions for the aircraft, the vehicle, and the wind, indicator1142, and recommendation1144.FIG. 11shows that current vehicle/wind/aircraft data region1140indicates the prevailing conditions include a “Vehicle Speed/Direction” having a vehicle speed of “20” knots per hour (KPH) and a vehicle direction of “5°”; a “WoV Speed/Direction” indicating a wind-over-vehicle speed of “22 KPH” and a wind-over-vehicle direction of “305°”; an “Aircraft Airspeed” of “30 KPH”; an “Aircraft to Vehicle Closure Rate” of “21 KPH”; and an “Approach Angle” for the aircraft of “15° relative to vehicle”.

Current vehicle/wind/aircraft data region1140includes data about any limitations imposed upon the prevailing conditions; e.g., limitations due to a mission, limitations due to procedures/policy such as aircraft speed limits and allowed or restricted approaches to a vehicle. Examples of limitations imposed upon the prevailing conditions include, but are not limited to limitations on crab angles and closure rates discussed above at least in the context ofFIGS. 8, 9, and 10. In scenario1100and as shown inFIG. 11, the data about any limitations imposed upon the prevailing conditions includes indications that “[n]o limitations” are placed on either “crab angles” or “closure rates”.

Current vehicle/wind/aircraft data region1140also includes indicator1142that provides an indication that the prevailing conditions are “OUTSIDE OF” the wind-over-vehicle “ENVELOPE” and so “LANDING” is “NOT RECOMMENDED”. Recommendations1144provide recommendations and/or more detail about the indication displayed by indicator1142—FIG. 11shows that recommendations1144indicate a “request” that the “vehicle course change about 30° into the wind and/or” that the “vehicle” is to “slowdown”. Recommendations1144also reiterate the indication of indicator1142that “[l]anding of aircraft using aircraft retrieval system NOT recommended”.

Recommendations1144also include accept recommendation for vehicle control1150, which if selected, directs the computing device to generate and send a command to the vehicle to accept recommendations1144; that is, the command sent to the vehicle can include a command to the vehicle to change course about 30 degrees into the wind and/or to slow down the vehicle. In scenario1100, accept recommendation for vehicle control1150is selected, which causes the computing device to send a command to the vehicle to change course about 30 degrees into the wind. The vehicle receives the command and subsequently changes course about 30 degrees into the wind. After the vehicle changes course about 30 degrees into the wind, scenario1100continues with the computing device updating the display of user interface1110to the display illustrated byFIG. 12.

FIG. 12shows that display region1112of user interface1110includes graph1210, display closure rate plot control1124, and display crab angle plot control1126. Graph1120includes wind-over-vehicle envelope1122, and current position1220illustrated using a black star. Wind-over-vehicle envelope1122, display closure rate plot control1124, and display crab angle plot control1126are discussed above in more detail at least in the context ofFIG. 11Current position1220illustrates how prevailing conditions for the aircraft, the vehicle, and the wind at a time graph1210is displayed relate to wind-over-vehicle envelope1122.FIG. 12shows that current position1220is inside of wind-over-vehicle envelope1122and therefore retrieval of the aircraft under the prevailing conditions is likely to be successful and/or safe.

Current vehicle/wind/aircraft data region1140includes data about the prevailing conditions for the aircraft, the vehicle, and the wind, indicator1232, and recommendation1234.FIG. 12shows that current vehicle/wind/aircraft data region1140indicates the prevailing conditions include a “Vehicle Speed/Direction” having a vehicle speed of “15 KPH” and a vehicle direction of “340°”; a “WoV Speed/Direction” indicating a wind-over-vehicle speed of “20 KPH” and a wind-over-vehicle direction of “330°”; an “Aircraft Airspeed” of “30 KPH”; an “Aircraft to Vehicle Closure Rate” of “26 KPH”; and an “Approach Angle” for the aircraft of “15° relative to vehicle”.

Current vehicle/wind/aircraft data region1140includes data about any limitations imposed upon the prevailing conditions; as shown inFIG. 12, the data about any limitations imposed upon the prevailing conditions includes indications that “[n]o limitations” are placed on either “crab angles” or “closure rates”. Current vehicle/wind/aircraft data region1140also includes indicator1232that provides an indication that the prevailing conditions are “INSIDE” the wind-over-vehicle “ENVELOPE”. Recommendations1234provide recommendations and/or more detail about the indication displayed by indicator1232—FIG. 12shows that recommendations1234include a recommendation to “[m]aintain current heading and speed for both aircraft and vehicle” and that it is “OK”; i.e., likely safe “to land aircraft using aircraft retrieval system.”

Scenario1100continues with display closure rate plot control1124of user interface1110being selected. After display closure rate plot control1124is selected, the computing device determines a closure rate plot and changes a display in display region1112from displaying graph1210with wind-over-vehicle envelope to a display of a closure-rate plot.

FIG. 13shows user interface1110of scenario1100after the computing device has changed display region1112to display closure rate plot1312. Display region1112of user interface1110includes closure rate plot1312, display wind-over-vehicle envelope control1314, and display crab angle plot control1126. Closure rate plot1312, which is plotted on graph1310, depicts of closure rates between the vehicle and the aircraft of scenario over a range of wind-over-vehicle directions. The indications of vehicle1350and aircraft1360in graph1310illustrate how prevailing conditions for the vehicle and the aircraft relate to closure rate plot1312. In particular, closure rate plot1312shows aircraft1360approaching vehicle1350at a vehicle-relative approach path direction of approximately 195 degrees and a closure rate of approximately 26 KPH. Closure rate plot1312also includes vector1362from a current position of aircraft1360with respect to graph1310to recommended position1364with respect to graph1310, where recommended position1364corresponds to a wind-over-vehicle direction of approximately 195 degrees and a closure rate of approximately 18 KPH.

Display crab angle plot control1126is discussed above in more detail at least in the context ofFIG. 11. Display wind-over-vehicle envelope control1314replaced display crab angle plot control1126after closure rate plot1312was displayed by user interface1110, as a wind-over-vehicle envelope was no longer being displayed. Display wind-over-vehicle envelope control1314, when selected, instructs user interface1110to display a graph with a wind-over-vehicle envelope, such discussed above at least in the context ofFIGS. 8-12.

Current vehicle/wind/aircraft data region1140includes data about the prevailing conditions for the aircraft, the vehicle, and the wind, indicator1332, and recommendation1334.FIG. 11shows that current vehicle/wind/aircraft data region1140indicates the prevailing conditions include a “Vehicle Speed/Direction” having a vehicle speed of “10 KPH” and a vehicle direction of “340°”; a “WoV Speed/Direction” indicating a wind-over-vehicle speed of “3 KPH” and a wind-over-vehicle direction of “200°”; an “Aircraft Airspeed” of “23 KPH”; an “Aircraft to Vehicle Closure Rate” of “26 KPH”; and an “Approach Angle” for the aircraft of “15° relative to vehicle”. Current vehicle/wind/aircraft data region1140includes data about any limitations imposed upon the prevailing conditions; as shown inFIG. 13, the data about any limitations imposed upon the prevailing conditions includes indications that “[n]o limitations” are placed on either “crab angles” or “closure rates”.

Current vehicle/wind/aircraft data region1140also includes indicator1332that provides an indication that the prevailing conditions indicate the aircraft is “Exceeding Closure Rate”. Recommendations1334provide recommendations and/or more detail about the indication displayed by indicator1332—FIG. 13shows that recommendations1334include a recommendation to “Change airspeed and/or aircraft heading to align velocity relative to vehicle with vector1362”.

Recommendations1334also include accept recommendation for aircraft control1370, which if selected, directs the computing device to generate and send a command to the vehicle to accept recommendations1334; that is, the command sent to the aircraft can include a command to the aircraft to approach the vehicle so that a resulting wind-over-vehicle direction is approximately 195 degrees and a closure rate is approximately 18 KPH. In scenario1100, accept recommendation for aircraft control1370is selected, which causes the computing device to send a command to the aircraft to change its approach the vehicle to a vehicle-relative approach path direction of approximately 195 degrees and a closure rate of approximately 18 KPH. The aircraft receives the command and subsequently changes course to approach the vehicle so that a wind-over-vehicle direction is approximately 195 degrees and a closure rate of the aircraft is approximately 18 KPH. After the aircraft changes its course as indicated above, scenario1100ends.

In related scenarios, the aircraft is retrieved at the vehicle following guidance and commands provided from the computing device (in response to selections of user interface1110) to the vehicle and/or the aircraft. In some of these related scenarios, the aircraft is retrieved at the vehicle using an aircraft retrieval system; e.g., aircraft retrieval system330; aircraft retrieval system340.

The novel features believed characteristic of the illustrative embodiments are set forth in the appended claims. The illustrative embodiments, however, as well as a preferred mode of use, further objectives and descriptions thereof, will best be understood by reference to the present specification when read in conjunction with the accompanying drawings in which some, but not all of the disclosed embodiments may be shown.

It should be understood that for this and other processes and methods disclosed herein, flowcharts show functionality and operation of one possible implementation of present embodiments. In this regard, each block may represent a module, a segment, or a portion of program code, which includes one or more instructions executable by a processor for implementing specific logical functions or steps in the process. The program code may be stored on any type of computer readable medium or data storage, for example, such as a storage device including a disk or hard drive. Further, the program code can be encoded on a computer-readable storage media in a machine-readable format, or on other non-transitory media or articles of manufacture. The computer readable medium may include non-transitory computer readable medium or memory, for example, such as computer-readable media that stores data for short periods of time like register memory, processor cache and Random Access Memory (RAM). The computer readable medium may also include non-transitory media, such as secondary or persistent long term storage, like read only memory (ROM), optical or magnetic disks, compact-disc read only memory (CD-ROM), for example. The computer readable media may also be any other volatile or non-volatile storage systems. The computer readable medium may be considered a tangible computer readable storage medium, for example.

In addition, each block in the disclosed flowcharts may represent circuitry that is wired to perform the specific logical functions in the process. Alternative implementations are included within the scope of the example embodiments of the present disclosure in which functions may be executed out of order from that shown or discussed, including substantially concurrent or in reverse order, depending on the functionality involved, as would be understood by those reasonably skilled in the art.