UAV PARACHUTE DEPLOYMENT SYSTEMS AND METHODS

Rescue parachute deployment systems (RPDSs) and related techniques are provided to improve the safety and operational flexibility of unmanned aerial vehicles (UAVs). An RPDS includes a canopy assembly, a rotor guard disposed at least partially about the canopy assembly and configured to protect the canopy assembly from rotor strike damage as the canopy assembly is launched through a rotor plane of the UAV, and an ejector assembly configured to deploy the rotor guard into and the canopy assembly through a rotor plane of the UAV. The RPDS may also include a logic device coupled to and/or integrated with the ejector assembly and/or the UAV that is configured to determine a rescue parachute launch condition is active and to control the ejector assembly to deploy the canopy assembly through the rotor plane of the UAV.

TECHNICAL FIELD

The present invention relates generally to parachute deployment and, more particularly, to systems and methods for rescue parachute deployment by relatively lightweight unmanned aircraft.

BACKGROUND

Modern unmanned aircraft systems (UASs), which may include one or a variety of different unmanned aerial vehicles (UAVs), are often expected to operate over long distances and in all types of environments; rural, urban, and over other populated and/or unpopulated areas. Operation of systems incorporating such unmanned flight platforms may include real-time wireless transmissions between the platform and a remote base station, which may itself include a display to efficiently convey telemetry, imagery, and/or other sensor data captured by the platform to an operator. An autopilot or an operator may pilot or otherwise assist in or guide control of an unmanned flight platform throughout an entire mission relying solely on received data provided by the unmanned platform.

Flight of a UAV over populated land and/or structures is increasingly regulated and may require installation of safety measures designed to reduce and/or eliminate risk of damage to person and property as a result of a platform navigation crisis, including loss of propulsion power. Moreover, UAVs are increasingly used to provide a variety of transport and/or delivery services, including transport of relatively expensive sensors for environmental survey and monitoring, for example, and/or transport and delivery of medicine and other relatively fragile cargo. Such safety measures can also be leveraged to reduce and/or eliminate risk of damage to the UAV, and any package or sensor suite coupled to the UAV, as a result of a platform navigation crisis. One safety measure addressing both operational needs is a rescue parachute, but conventional parachute deployment systems are too easily damaged or otherwise rendered inoperable by a typical UAV propulsion system and/or otherwise lack sufficiently reliable performance. Thus, there is a need for rescue parachute deployment systems and techniques for use with UASs to provide relatively reliable and high-performance countermeasures to a variety of UAV navigation crises.

SUMMARY

Unmanned aerial vehicle (UAV) rescue parachute deployment systems (RPDSs) and related techniques are provided to improve the operation of unmanned flight platforms. One or more embodiments of the described UAV RPDSs may advantageously include a canopy assembly, an ejector assembly, and a rotor guard configured to protect the canopy assembly as it is launched by the ejector assembly through a rotor plane of the UAV. Embodiments may also include an orientation and/or position sensor to measure dynamic motion of the RPDS, a deployment controller to control operation of the system, and one or more additional sensors to measure and provide sensor data corresponding to maneuvering and/or other operation of the flight platform and/or the RPDS. In various embodiments, such additional sensors may include one or more visible spectrum and/or infrared cameras and/or other remote sensor systems coupled to the flight platform.

In one embodiment, a system includes a canopy assembly including a bundled canopy coupled to the RPDS and/or the UAV via a shock cord and a plurality of suspension lines; a rotor guard disposed at least partially about the canopy assembly and configured to protect the canopy assembly from rotor strike damage as the canopy assembly is launched through a rotor plane of the UAV; and an ejector assembly including a launch platform and/or a plurality of launch impulse interfaces configured to deploy the rotor guard into and the canopy assembly through a rotor plane of the UAV. The system may also include a logic device coupled to and/or integrated with the ejector assembly and/or the UAV. The logic device may be configured to determine a rescue parachute launch condition is active and to control the ejector assembly to deploy the canopy assembly through the rotor plane of the UAV.

In another embodiment, a method includes determining a rescue parachute launch condition for a UAV is active and controlling an ejector assembly of an RPDS coupled to the UAV to deploy a rotor guard into and a canopy assembly through a rotor plane of the UAV. The canopy assembly may include a bundled canopy coupled to the RPDS and/or the UAV via a shock cord and a plurality of suspension lines, and the rotor guard may be disposed at least partially about the canopy assembly and configured to protect the canopy assembly from rotor strike damage as the canopy assembly is launched through the rotor plane of the UAV.

DETAILED DESCRIPTION

Modern unmanned aerial vehicles (UAVs) are able to operate over long distances and in all environments. High efficiency propulsion systems for UAVs can require large diameter propellers or rotors, and compact arrangement of vertically aligned large diameter rotors about a UAV airframe can leave very little if any space for other components that require or at least benefit from up-facing installation, such as global navigation satellite system (GNSS) antennas (e.g., to provide as unobscured and as large a sky view as possible) and rescue parachute deployment systems (e.g., to provide the most expedient countermeasure to the most common UAV navigational crises). Embodiments described herein address the conflicting operational needs of UAV propulsion systems and rescue parachute deployment systems (RPDSs).

For example, embodiments of the RPDSs described herein may include a relatively rigid rotor guard disposed about the primary rescue parachute/canopy assembly (e.g., canopy, support lines, shock cord) that allows the RPDS to be mounted beneath a ‘copter-type’ UAV’s rotor plane or disk (e.g., the area(s) swept through by the UAV’s rotors) and to launch the canopy assembly through the UAV’s rotor disk reliably and without risking damage to the canopy assembly (e.g., in the event the UAV’s rotors are rotating at a significant RPM when the canopy assembly is launched). Advantageously, such RPDS mounting is also beneath a typical UAV GNSS antenna’s operational field of view (e.g., a dome aligned with a vertical axis of the UAV), which allows the RPDS to deploy a rescue parachute vertically upward without interfering with operation of the GNSS and/or over-utilizing the typically limited area above the UAV that is unobstructed by rotors, navigation sensors, cameras, aerodynamic features, and/or other elements of the UAV.

Embodiments therefore provide systems and methods to deploy rescue parachutes in UAVs, where the canopy of the rescue parachute, and its connection to the UAV, are protected while they are deployed through the UAV’s rotor disk(s). As a result, embodiments described herein can be safety installed on the UAV where conventional systems would otherwise interfere with other parts of the UAV or cannot be installed at all. Moreover, embodiments are able to deploy rescue parachutes in a manner that can reduce and/or arrest undesired momentum of a coupled UAV more quickly than systems unable to deploy safely through a UAV’s rotor disk(s).

In some embodiments, an RPDS may include a capsule-shaped rotor guard (e.g., parachute container) implemented by two interlocking half-capsule shells each including a smooth/aerodynamic half-dome-shaped top and half-cylindrical body shaped to provide a shock cord orifice for a canopy shock chord when the two half-capsule shells are interlocked with the canopy assembly disposed within. Each half-capsule shell may be made of relatively thin but strong plastic, such as polyethylene terephthalate (PET) (e.g., commonly used for carbonated drink bottles), which may be used to form each half-capsule shell by injection molding, 3d printing, and/or other plastic shell formation techniques. In such embodiments, the combination of the relatively thin and rigid interlocking shell with a tightly folded and/or rolled canopy assembly (e.g., working as internal cushioning) provides an impact resistant solution.

In related embodiments, an RPDS may include a capsule-shaped rotor guard implemented by a tapered cylindrical body or cup and a dome-shaped lid. The tapered cylindrical body and the dome-shaped lid may each be formed using materials and techniques similar to those used to form the two half-capsule shells described herein, for example, and may be formed according to similar thicknesses/rigidity characteristics. Such embodiments may include vent holes for pressure relief during parachute deployment and may include various spacer ribs and/or other alignment features to space the rotor guard from an ejector assembly of the RPDS to help ensure reliable launch of the rescue parachute even in relatively poor environmental conditions, such as those conducive to ice formation in narrow gaps.

In further embodiments, an RPDS may include a rotor guard implemented by a guard ring and a plurality of guide rods coupled to each other through the guard ring and configured to protect the canopy assembly from impact damage as the canopy assembly and the rotor guard are launched by the RPDS’s ejector assembly. Each guide rod can absorb and stop or deflect impacts from rotors, and the guard ring may be configured to connect all the pushrods and form them into a relatively rigid frame. Connecting the guide rods into a frame adds structural rigidity and prevents the rotor guard from losing its shape and jamming during deployment and rotor impacts. In various embodiments, the rotor guard may be packed into a disposable water- and UV-resistant pouch before being loaded into the ejector assembly of an RPDS. During deployment, the pouch may be pierced and opened by the top ends of guide rods, as described herein.

FIG.1illustrates a block diagram of an unmanned aircraft system (UAS)100including an unmanned aerial vehicle (UAV) rescue parachute deployment system (RPDS)160coupled to a UAV platform110in accordance with an embodiment of the disclosure. In some embodiments, system100may be configured to fly over a scene, through a structure, or approach a target and image or sense the scene, structure, or target, or portions thereof, using gimbal system122to aim imaging system/sensor payload140at the scene, structure, or target, or portions thereof. Resulting imagery and/or other sensor data may be processed (e.g., by sensor payload140, platform110, and/or base station130) and displayed to a user through use of user interface132(e.g., one or more displays such as a multi-function display (MFD), a portable electronic device such as a tablet, laptop, or smart phone, or other appropriate interface) and/or stored in memory for later viewing and/or analysis.

In various embodiments, system100may be configured to use such imagery and/or sensor data to control operation of platform110and/or sensor payload140, as described herein, such as controlling gimbal system122to aim sensor payload140towards a particular direction or controlling propulsion system124to move platform110to a desired position in a scene or structure or relative to a target. In related embodiments, system100may be configured to deliver or drop a package (e.g., payload140) at a desired location or structure or relative to a target. In all operational embodiments, system100may be configured to use such imagery and/or related sensor data to detect a UAV navigation crisis, such as unintended inverted flying, pitch and/or roll attitudes outside preselected safety ranges, unintended loss of altitude, entrance into an altitude or otherwise restricted airspace, and/or loss of power, for example, and to use RPDS160to deploy a rescue parachute (e.g., canopy assembly164) to cause platform110and/or payload140to safety descend to the ground without damaging platform110, payload140, other elements of system100, and/or underlying persons or property, as described herein.

In the embodiment shown inFIG.1, UAS100includes platform110, optional base station130, and at least one RPDS160. In general, platform110may be a mobile platform configured to move or fly and position payload140and/or platform110(e.g., relative to a designated or detected target). As shown inFIG.1, platform110may include one or more of a controller112, an orientation sensor114, a gyroscope/accelerometer116, a global navigation satellite system (GNSS)118, a communications module120, a gimbal system122, a propulsion system124, a RPDS coupler128, and other modules126. Sensor payload140and/or RPDS160may be physically coupled to platform110and be configured to capture sensor data (e.g., visible spectrum images, infrared images, narrow aperture radar data, analyte sensor data, orientation/attitude and/or position data, and/or other sensor data) of a target position, area, and/or object(s) as selected and/or framed by operation of platform110and/or base station130, for example, and/or associated with maneuvering or navigation of platform110, as described herein.

Operation of platform110may be substantially autonomous and/or partially or completely controlled by optional base station130, which may include one or more of a user interface132, a communications module134, and other modules136. In other embodiments, platform110may include one or more of the elements of base station130, such as with various types of manned aircraft, terrestrial vehicles, and/or surface or subsurface watercraft. In some embodiments, one or more of the elements of system100may be implemented in a combined housing or structure that can be coupled to or within platform110and/or held or carried by a user of system100.

Controller112may be implemented as any appropriate logic device (e.g., processing device, microcontroller, processor, application specific integrated circuit (ASIC), field programmable gate array (FPGA), memory storage device, memory reader, or other device or combinations of devices) that may be adapted to execute, store, and/or receive appropriate instructions, such as software instructions implementing a control loop for controlling various operations of platform110and/or other elements of system100, for example. Such software instructions may also implement methods for processing infrared images and/or other sensor signals, determining sensor information, providing user feedback (e.g., through user interface132), querying devices for operational parameters, selecting operational parameters for devices, or performing any of the various operations described herein (e.g., operations performed by logic devices of various devices of system100).

In addition, a non-transitory medium may be provided for storing machine readable instructions for loading into and execution by controller112. In these and other embodiments, controller112may be implemented with other components where appropriate, such as volatile memory, non-volatile memory, one or more interfaces, and/or various analog and/or digital components for interfacing with devices of system100. For example, controller112may be adapted to store sensor signals, sensor information, parameters for coordinate frame transformations, calibration parameters, sets of calibration points, and/or other operational parameters, over time, for example, and provide such stored data to a user using user interface132. In some embodiments, controller112may be integrated with one or more other elements of platform110, for example, or distributed as multiple logic devices within platform110, base station130, and/or sensor payload140.

In some embodiments, controller112may be configured to substantially continuously monitor and/or store the status of and/or sensor data provided by one or more elements of platform110, sensor payload140, RPDS160, and/or base station130, such as the position and/or orientation of platform110, sensor payload140, and/or base station130, for example, and the status of a communication link established between platform110, sensor payload140, RPDS160, and/or base station130. Such communication links may be configured to be established and then used to transmit data between elements of system100substantially continuously throughout operation of system100, where such data includes various types of sensor data, control parameters, and/or other data.

Orientation sensor114may be implemented as one or more of a compass, float, accelerometer, and/or other device capable of measuring an orientation of platform110(e.g., magnitude and direction of roll, pitch, and/or yaw, relative to one or more reference orientations such as gravity and/or Magnetic North), optional gimbal system122, imaging system/sensor payload140, and/or other elements of system100, and providing such measurements as sensor signals and/or data that may be communicated to various devices of system100. Gyroscope/accelerometer116may be implemented as one or more electronic sextants, semiconductor devices, integrated chips, accelerometer sensors, accelerometer sensor systems, or other devices capable of measuring angular velocities/accelerations and/or linear accelerations (e.g., direction and magnitude) of platform110and/or other elements of system100and providing such measurements as sensor signals and/or data that may be communicated to other devices of system100(e.g., user interface132, controller112).

GNSS118may be implemented according to any global navigation satellite system, including a GPS, GLONASS, and/or Galileo based receiver and/or other device capable of determining absolute and/or relative position of platform110(e.g., or an element of platform110) based on wireless signals received from space-born and/or terrestrial sources (e.g., eLoran, and/or other at least partially terrestrial systems), for example, and capable of providing such measurements as sensor signals and/or data (e.g., coordinates) that may be communicated to various devices of system100. In some embodiments, GNSS118may include an altimeter, for example, or may be used to provide an absolute altitude.

Communications module120may be implemented as any wired and/or wireless communications module configured to transmit and receive analog and/or digital signals between elements of system100. For example, communications module120may be configured to receive flight control signals and/or data from base station130and provide them to controller112and/or propulsion system124. In other embodiments, communications module120may be configured to receive images and/or other sensor information (e.g., visible spectrum and/or infrared still images or video images) from sensor payload140and relay the sensor data to controller112and/or base station130. In further embodiments, communications module120may be configured to receive sensor information from RPDS160and relay the sensor data to controller112and/or base station130. In various embodiments, communications module120may be configured to support spread spectrum transmissions, for example, and/or multiple simultaneous communications channels between elements of system100. Wireless communication links may include one or more analog and/or digital radio communication links, such as WiFi and others, as described herein, and may be direct communication links established between elements of system100, for example, or may be relayed through one or more wireless relay stations configured to receive and retransmit wireless communications.

In some embodiments, communications module120may be configured to monitor the status of a communication link established between platform110, sensor payload140, and/or base station130. Such status information may be provided to controller112, for example, or transmitted to other elements of system100for monitoring, storage, or further processing, as described herein. Communication links established by communication module120may be configured to transmit data between elements of system100substantially continuously throughout operation of system100, where such data includes various types of sensor data, control parameters, and/or other data, as described herein.

In some embodiments, when present, optional gimbal system122may be implemented as an actuated gimbal mount, for example, that may be controlled by controller112to stabilize sensor payload140relative to a target or to aim and/or orient sensor payload140according to a desired direction and/or relative position. As such, gimbal system122may be configured to provide a relative orientation of sensor payload140(e.g., relative to an orientation of platform110) to controller112and/or communications module120(e.g., gimbal system122may include its own orientation sensor114). In other embodiments, gimbal system122may be implemented as a gravity driven mount (e.g., non-actuated). In various embodiments, gimbal system122may be configured to provide power, support wired communications, and/or otherwise facilitate operation of articulated sensor/sensor payload140. In further embodiments, gimbal system122may be configured to couple to a laser pointer, range finder, and/or other device, for example, to support, stabilize, power, and/or aim multiple devices (e.g., sensor payload140and one or more other devices) substantially simultaneously. In still further embodiments, gimbal system122may be implemented as an actuated release mechanism to decouple and/or drop payload140according to control signals provided by controller112and/or relayed by communications module120.

Propulsion system124may be implemented as one or more propellers, turbines, or other thrust-based propulsion systems, and/or other types of propulsion systems that can be used to provide motive force and/or lift to platform110and/or to steer platform110. In some embodiments, propulsion system124may include multiple propellers (e.g., a tri, quad, hex, oct, or other type “copter”) that can be controlled (e.g., by controller112) to provide lift and motion for platform110and to provide an orientation for platform110. In other embodiments, propulsion system110may be configured primarily to provide thrust while other structures of platform110provide lift, such as in a fixed wing embodiment (e.g., where wings provide the lift) and/or an aerostat embodiment (e.g., balloons, airships, hybrid aerostats). In various embodiments, propulsion system124may be implemented with a portable power supply, such as a battery and/or a combustion engine/generator and fuel supply.

Other modules126may include other and/or additional sensors, actuators, communications modules/nodes, and/or user interface devices, for example, and may be used to provide additional environmental information related to operation of platform110, for example. In some embodiments, other modules126may include a humidity sensor, a wind and/or water temperature sensor, a barometer, an altimeter, a radar system, a proximity sensor, a visible spectrum camera or infrared camera (with an additional mount), an irradiance detector, and/or other environmental sensors providing measurements and/or other sensor signals that can be displayed to a user and/or used by other devices of system100(e.g., controller112) to provide operational control of platform110and/or system100.

In some embodiments, other modules126may include one or more actuated and/or articulated devices (e.g., multi-spectrum active illuminators, visible and/or IR cameras, radars, sonars, and/or other actuated devices) coupled to platform110, where each actuated device includes one or more actuators adapted to adjust an orientation of the device, relative to platform110, in response to one or more control signals (e.g., provided by controller112). In particular, other modules126may include a stereo vision system configured to provide image data that may be used to calculate or estimate a position of platform110, for example, or to calculate or estimate a relative position of a navigational hazard in proximity to platform110. In various embodiments, controller130may be configured to use such proximity and/or position information to help safely pilot platform110and/or monitor communication link quality, as described herein.

In various embodiments, RPDS coupler128may be implemented as a slot-slide mount, a latching mechanism, and/or other coupler that may be permanently mounted to platform110to provide a mounting position and/or orientation for RPDS160relative to a center of gravity of platform110, relative to propulsion system124, and/or relative to other elements of and/or orientations associated with platform110. In addition, RPDS coupler128may be configured to provide power, support wired communications, and/or otherwise facilitate operation of RPDS160, as described herein. As such, RPDS coupler128may be configured to provide a power, telemetry, and/or other sensor data interface between platform110and RPDS160.

User interface132of base station130may be implemented as one or more of a display, a touch screen, a keyboard, a mouse, a joystick, a knob, a steering wheel, a yoke, and/or any other device capable of accepting user input and/or providing feedback to a user. In various embodiments, user interface132may be adapted to provide user input (e.g., as a type of signal and/or sensor information transmitted by communications module134of base station130) to other devices of system100, such as controller112. User interface132may also be implemented with one or more logic devices (e.g., similar to controller112) that may be adapted to store and/or execute instructions, such as software instructions, implementing any of the various processes and/or methods described herein. For example, user interface132may be adapted to form communication links, transmit and/or receive communications (e.g., visible spectrum and/or infrared images and/or other sensor signals, control signals, sensor information, user input, and/or other information), for example, or to perform various other processes and/or methods described herein.

In one embodiment, user interface132may be adapted to display a time series of various sensor information and/or other parameters as part of or overlaid on a graph or map, which may be referenced to a position and/or orientation of platform110and/or other elements of system100. For example, user interface132may be adapted to display a time series of positions, headings, and/or orientations of platform110and/or other elements of system100overlaid on a geographical map, which may include one or more graphs indicating a corresponding time series of actuator control signals, sensor information, and/or other sensor and/or control signals.

In some embodiments, user interface132may be adapted to accept user input including a user-defined target heading, waypoint, route, and/or orientation for an element of system100, for example, and to generate control signals to cause platform110to move according to the target heading, route, and/or orientation, or to aim sensor payload140accordingly. In other embodiments, user interface132may be adapted to accept user input modifying a control loop parameter of controller112, for example. In further embodiments, user interface132may be adapted to accept user input including a user-defined target attitude, orientation, and/or position for an actuated or articulated device (e.g., sensor payload140) associated with platform110, for example, and to generate control signals for adjusting an orientation and/or position of the actuated device according to the target attitude, orientation, and/or position. Such control signals may be transmitted to controller112(e.g., using communications modules134and120), which may then control platform110and/or elements of platform110accordingly.

Communications module134may be implemented as any wired and/or wireless communications module configured to transmit and receive analog and/or digital signals between elements of system100. For example, communications module134may be configured to transmit flight control signals from user interface132to communications module120or144. In other embodiments, communications module134may be configured to receive sensor data (e.g., visible spectrum and/or infrared still images or video images, or other sensor data) from sensor payload140. In some embodiments, communications module134may be configured to support spread spectrum transmissions, for example, and/or multiple simultaneous communications channels between elements of system100. In various embodiments, communications module134may be configured to monitor the status of a communication link established between base station130, sensor payload140, and/or platform110(e.g., including packet loss of transmitted and received data between elements of system100, such as with digital communication links), as described herein. Such status information may be provided to user interface132, for example, or transmitted to other elements of system100for monitoring, storage, or further processing, as described herein.

Other modules136of base station130may include other and/or additional sensors, actuators, communications modules/nodes, and/or user interface devices used to provide additional environmental information associated with base station130, for example. In some embodiments, other modules136may include a humidity sensor, a wind and/or water temperature sensor, a barometer, a radar system, a visible spectrum camera, an infrared camera, a GNSS, an analyte sensor system, and/or other environmental sensors providing measurements and/or other sensor signals that can be displayed to a user and/or used by other devices of system100(e.g., controller112) to provide operational control of platform110and/or system100or to process sensor data to compensate for environmental conditions, such as an water content in the atmosphere approximately at the same altitude and/or within the same area as platform110and/or base station130, for example. In some embodiments, other modules136may include one or more actuated and/or articulated devices (e.g., multi-spectrum active illuminators, visible and/or IR cameras, radars, sonars, and/or other actuated devices), where each actuated device includes one or more actuators adapted to adjust an orientation of the device in response to one or more control signals (e.g., provided by user interface132).

In embodiments where imaging system/sensor payload140is implemented as an imaging device, imaging system/sensor payload140may include imaging module142, which may be implemented as a cooled and/or uncooled array of detector elements, such as visible spectrum and/or infrared sensitive detector elements, including quantum well infrared photodetector elements, bolometer or microbolometer based detector elements, type II superlattice based detector elements, and/or other infrared spectrum detector elements that can be arranged in a focal plane array. In various embodiments, imaging module142may include one or more logic devices (e.g., similar to controller112) that can be configured to process imagery captured by detector elements of imaging module142before providing the imagery to memory146or communications module144. More generally, imaging module142may be configured to perform any of the operations or methods described herein, at least in part, or in combination with controller112and/or user interface132.

In some embodiments, sensor payload140may be implemented with a second or additional imaging modules similar to imaging module142, for example, that may include detector elements configured to detect other electromagnetic spectrums, such as visible light, ultraviolet, and/or other electromagnetic spectrums or subsets of such spectrums. In various embodiments, such additional imaging modules may be calibrated or registered to imaging module142such that images captured by each imaging module occupy a known and at least partially overlapping field of view of the other imaging modules, thereby allowing different spectrum images to be geometrically registered to each other (e.g., by scaling and/or positioning). In some embodiments, different spectrum images may be registered to each other using pattern recognition processing in addition or as an alternative to reliance on a known overlapping field of view.

Communications module144of sensor payload140may be implemented as any wired and/or wireless communications module configured to transmit and receive analog and/or digital signals between elements of system100. For example, communications module144may be configured to transmit infrared images from imaging module142to communications module120or134. In other embodiments, communications module144may be configured to receive control signals (e.g., control signals directing capture, focus, selective filtering, and/or other operation of sensor payload140) from controller112and/or user interface132. In some embodiments, communications module144may be configured to support spread spectrum transmissions, for example, and/or multiple simultaneous communications channels between elements of system100. In various embodiments, communications module144may be configured to monitor the status of a communication link established between sensor payload140, base station130, and/or platform110(e.g., including packet loss of transmitted and received data between elements of system100, such as with digital communication links), as described herein. Such status information may be provided to imaging module142, for example, or transmitted to other elements of system100for monitoring, storage, or further processing, as described herein.

Memory146may be implemented as one or more machine readable mediums and/or logic devices configured to store software instructions, sensor signals, control signals, operational parameters, calibration parameters, infrared images, and/or other data facilitating operation of system100, for example, and provide it to various elements of system100. Memory146may also be implemented, at least in part, as removable memory, such as a secure digital memory card for example including an interface for such memory.

Orientation sensor148of sensor payload140may be implemented similar to orientation sensor114or gyroscope/accelerometer116, and/or any other device capable of measuring an orientation of sensor payload140, imaging module142, and/or other elements of sensor payload140(e.g., magnitude and direction of roll, pitch, and/or yaw, relative to one or more reference orientations such as gravity and/or Magnetic North) and providing such measurements as sensor signals that may be communicated to various devices of system100. Gyroscope/ accelerometer (e.g., angular motion sensor)150of sensor payload140may be implemented as one or more electronic sextants, semiconductor devices, integrated chips, accelerometer sensors, accelerometer sensor systems, or other devices capable of measuring angular velocities/accelerations (e.g., angular motion) and/or linear accelerations (e.g., direction and magnitude) of sensor payload140and/or various elements of sensor payload140and providing such measurements as sensor signals that may be communicated to various devices of system100.

Other modules152of sensor payload140may include other and/or additional sensors, actuators, communications modules/nodes, cooled or uncooled optical filters, and/or user interface devices used to provide additional environmental information associated with sensor payload140, for example. In some embodiments, other modules152may include a humidity sensor, a wind and/or water temperature sensor, a barometer, a radar system, a visible spectrum camera, an infrared camera, a GNSS, an analyte sensor system, and/or other environmental sensors providing measurements and/or other sensor signals that can be displayed to a user and/or used by imaging module142or other devices of system100(e.g., controller112) to provide operational control of platform110and/or system100or to process imagery to compensate for environmental conditions.

In alternative embodiments, where payload140is implemented as a package to be delivered to a target position, location, or destination, gimbal system122may be implemented as an actuated payload coupler configured to decouple or release or drop payload140(e.g., as controlled by controller112, user interface132, and/or other elements of system100) from platform110. In related embodiments, RPDS160may be coupled to payload140(e.g., via a shock cord or other element of RPDS160) and be configured to deploy canopy assembly168to protect payload140after it is decoupled from platform110(e.g. while in flight) and as it descends from platform110to a desired delivery location, as described herein. In such embodiments, RPDS160may be referred to as a recovery parachute deployment system.

More generally, as shown inFIG.1, RPDS160may be implemented as a parachute deployment system configured to deploy a canopy assembly168configured to reduce and/or arrest undesired momentum of platform110, such as during and/or to compensate for a navigation crisis, as described herein. For example, in various embodiments, controller112and/or other elements of system100may be configured to detect unintended inverted flying of platform110, unsafe attitude excursions of platform110(e.g., outside preselected safety ranges), unintended and/or unrecoverable losses of altitude of platform110, entrance of platform110into a restricted altitude or airspace, loss of propulsion or navigation control power for platform110, loss of communication between platform110and base station110and/or other UAV navigation crises, for example, and to control RPDS160to deploy a rescue parachute (e.g., canopy assembly164) to cause platform110and/or payload140to safety descend to the ground without damaging platform110, payload140, other elements of system100, and/or underlying persons or property, as described herein.

In the embodiment shown inFIG.1, RPDS160includes optional deployment controller162, ejector assembly164, rotor guard166, canopy assembly168, and other modules170. In various embodiments, rotor guard166may be disposed substantially about canopy assembly168and ejector assembly164may be configured to launch rotor guard166and canopy assembly168through a rotor plane of propulsion system124and/or platform110. By deploying canopy assembly168through a rotor plane of platform110, RPDS160is able to reduce a momentum of platform110and/or payload140to a relatively safe momentum or associated descent velocity more quickly and at lower deployment altitudes achievable by systems unable to reliably launch through such rotor plane.

As described more fully herein with reference toFIGS.3A-7C, rotor guard166may be implemented by one or more relatively lightweight and rigid shells, cups, lids, frames, and/or rods configured to enclose and protect canopy assembly168from rotor impacts as it is launched through a rotor plane of platform110. Rotor guard166may be formed from metal or plastic (e.g., polylactic acid/polylactide (PLA), PET) or combinations of those, for example, and may be manufactured via additive manufacturing (e.g., 3D printing), injection molding, machining, casting, and/or other metal and/or plastic manufacturing techniques. In embodiments where rotor guard166is capsule shaped, rotor guard166may be formed according to shells, body walls, and/or dome shaped lid thicknesses of approximately 1 mm. Rotor guard166may include various vent holes, shock cord orifices, spacer ribs, alignment features, and/or other structures configured to facilitate packaging of canopy assembly168and/or launch by ejector assembly164.

Canopy assembly168may include a canopy/parachute shroud, suspension lines, link collectors, swivels, a shock cord, and/or other rescue parachute elements, for example, that can be wrapped and/or folded into a bundle that can be packed within rotor guard166and launched by ejector assembly164. Ejector assembly164may include one or more launch impulse generators configured to provide sufficient impulse to rotor guard166and/or canopy assembly168to launch rotor guard166and canopy assembly168and reliably deploy canopy assembly168through a rotor plane of platform110.

Optional deployment controller162may be configured to receive control signals and/or telemetry from platform110(e.g., via communications module120and/or RPDS coupler128), for example, and/or to receive telemetry from sensors integrated with payload140(e.g., orientation sensor148, gyroscope/accelerometer150, other modules152) and/or RPDS160(e.g., other modules170), and control operation of ejector assembly164based, at least in part, on the received control signals and/or telemetry. In some embodiments, deployment controller162may be configured to control operation of ejector assembly164independent of control signals and/or telemetry provided by other elements of platform110, base station130, and/or system100.

More generally, deployment controller162may be implemented as one or more of any appropriate logic device (e.g., processing device, microcontroller, processor, application specific integrated circuit (ASIC), field programmable gate array (FPGA), memory storage device, memory reader, or other device or combinations of devices) that may be adapted to execute, store, and/or receive appropriate instructions, such as software instructions implementing a control loop for controlling various operations of RPDS160and/or other elements of RPDS160, for example. Such software instructions may also implement methods for processing sensor signals, determining sensor information, providing user feedback (e.g., through user interface132via communications through RPDS coupler128and/or communications module120), querying devices for operational parameters, selecting operational parameters for devices, or performing any of the various operations described herein.

In addition, a non-transitory medium may be provided for storing machine readable instructions for loading into and execution by deployment controller162, and such non-transitory medium may be implemented as internal and/or external memory and/or associated interfaces. In these and other embodiments, deployment controller162may be implemented with other components where appropriate, such as volatile memory, non-volatile memory, one or more interfaces, and/or various analog and/or digital components for interfacing with modules of RPDS160and/or devices of system100. For example, deployment controller162may be adapted to store sensor signals, sensor information, parameters for coordinate frame transformations, calibration parameters, sets of calibration points, and/or other operational parameters, over time, for example, and provide such stored data to a user using user interface132. In some embodiments, deployment controller162may be integrated with one or more other elements of RPDS160, for example, or distributed as multiple logic devices within platform110, base station130, and/or RPDS160.

In some embodiments, controller112may be configured to substantially continuously monitor and/or store the status of and/or sensor data provided by one or more elements of RPDS160, such as the position and/or orientation of platform110, RPDS160, and/or base station130, for example, and the status of a communication link established between platform110, RPDS160, and/or base station130. Such communication links may be configured to be established and then transmit data between elements of system100substantially continuously throughout operation of system100, where such data includes various types of sensor data, control parameters, and/or other data.

Other modules170of RPDS160may include other and/or additional sensors, actuators, communications modules/nodes, and/or user interface devices used to provide additional operational and/or environmental information associated with RPDS160, for example. In some embodiments, other modules170may include a humidity sensor, a wind and/or water temperature sensor, a barometer, an orientation sensor, a gyroscope/accelerometer, a GNSS, and/or other navigational or environmental sensors providing measurements and/or other sensor signals that can be displayed to a user and/or used by deployment controller162or other devices of system100(e.g., controller112) to provide operational control of RPDS160, platform110, and/or system100, as described herein.

In some embodiments, other modules170may include a communications module implemented as any wired and/or wireless communications module configured to transmit and receive analog and/or digital signals between elements of system100. For example, such communications module may be configured to receive control signals (e.g., control signals directing operation of RPDS160) from controller112and/or user interface132. In some embodiments, such communications module may be configured to support spread spectrum transmissions, for example, and/or multiple simultaneous communications channels between elements of system100. In other embodiments, other modules170may include a power supply implemented as any power storage device configured to provide enough power to each element of RPDS160to keep all such elements active and operable while RPDS160is otherwise disconnected from external power (e.g., provided by platform110and/or base station130). In various embodiments, such power supply may be implemented by a supercapacitor so as to be relatively lightweight and facilitate flight of platform110.

Although system100is shown inFIG.1with a single RPDS160coupled to platform110through RPDS coupler128, in other embodiments, system100may include multiple RPDSs160, each of which may be coupled to platform110(e.g., to assist in recovery of relatively large and/or heavy embodiments of platform110) and/or to payload140(e.g., though a coupler similar to RPDS coupler128but integrated with payload140). In some embodiments, one RPDS may be configured to assist in recovery of platform110, and another RPDS may be configured to assist in separate recovery of payload140, such as after decoupling of payload140from platform110.

In general, each of the elements of system100may be implemented with any appropriate logic device (e.g., processing device, microcontroller, processor, application specific integrated circuit (ASIC), field programmable gate array (FPGA), memory storage device, memory reader, or other device or combinations of devices) that may be adapted to execute, store, and/or receive appropriate instructions, such as software instructions implementing a method for providing sensor data and/or imagery, for example, or for transmitting and/or receiving communications, such as sensor signals, sensor information, and/or control signals, between one or more devices of system100.

In addition, one or more non-transitory mediums may be provided for storing machine readable instructions for loading into and execution by any logic device implemented with one or more of the devices of system100. In these and other embodiments, the logic devices may be implemented with other components where appropriate, such as volatile memory, non-volatile memory, and/or one or more interfaces (e.g., inter-integrated circuit (I2C) interfaces, mobile industry processor interfaces (MIPI), joint test action group (JTAG) interfaces (e.g., IEEE 1149.1 standard test access port and boundary-scan architecture), and/or other interfaces, such as an interface for one or more antennas, or an interface for a particular type of sensor).

Sensor signals, control signals, and other signals may be communicated among elements of system100using a variety of wired and/or wireless communication techniques, including voltage signaling, Ethernet, WiFi, Bluetooth, Zigbee, Xbee, Micronet, or other medium and/or short range wired and/or wireless networking protocols and/or implementations, for example. In such embodiments, each element of system100may include one or more modules supporting wired, wireless, and/or a combination of wired and wireless communication techniques. In some embodiments, various elements or portions of elements of system100may be integrated with each other, for example, or may be integrated onto a single printed circuit board (PCB) to reduce system complexity, manufacturing costs, power requirements, coordinate frame errors, and/or timing errors between the various sensor measurements.

Each element of system100may include one or more batteries, capacitors, or other electrical power storage devices, for example, and may include one or more solar cell modules or other electrical power generating devices. In some embodiments, one or more of the devices may be powered by a power source for platform110, using one or more power leads. Such power leads may also be used to support one or more communication techniques between elements of system100.

In various embodiments, co-pilot station230may be implemented similarly relative to base station130, such as including similar elements and/or being capable of similar functionality. In some embodiments, co-pilot station230may include a number of displays so as to facilitate operation of RPDS160and/or various imaging and/or sensor payloads of mobile platforms110A-B, generally separate from piloting mobile platforms110A-B, and to facilitate substantially real time analysis, visualization, and communication of sensor data and corresponding directives, such as to first responders in contact with a co-pilot or user of system200. For example, base station130and co-pilot station230may each be configured to render any display views described herein.

Also shown inFIG.2are dashed arrows extending through RPDSs160and oriented perpendicular to the respective rotor planes of platforms110A and110B. With respect to ‘copter-type’ UAV/platform110A, the dashed arrow shows the direction rotor guard166and canopy assembly168are launched through the rotor plane defined by the multiple and roughly vertically aligned rotors (and their associated rotor disks) of platform110A. With respect to fixed wing-type UAV/platform110B, the dashed arrow shows the direction rotor guard166and canopy assembly168are launched through the rotor plane defined by the single pusher and longitudinally aligned rotor (and its associated rotor disk) of platform110B.

In particular, each dashed arrow illustrates how embodiments of RPDS160are able to reduce/arrest momentum of platforms110A and110B more quickly than alternative systems. For example, platform110A typically flies in the orientation shown inFIG.2, with each of the rotors aligned substantially vertically, and in the majority of navigation crises, the crisis begins while platform110A hovers or flies laterally in the shown orientation. As such, launch of canopy assembly168vertically along the direction of the dashed arrow, and through the corresponding rotor plane, typically results in the canopy inflating before platform110A has dropped more than 1-2 body heights in altitude, whereas lateral launch of canopy assembly168(or vertical down launch) would typically result in a free-fall drop of 5 or more body heights (e.g., partially dependent upon the length of the shock cord) and potentially in a relatively unstable pendulum swinging of platform110.

With respect to platform110B, platform110B typically flies laterally in the orientation shown inFIG.2, with its single pusher rotor aligned substantially laterally and substantially opposite the main momentum of platform110B, and in the majority of its navigation crises, the crisis begins while platform110B flies laterally in the shown orientation. As such, launch of canopy assembly168laterally along the direction of the dashed arrow, and through the corresponding rotor plane, typically results in the canopy inflating before platform110B has traveled more than 1-2 body lengths, and potentially before platform110B has dropped in altitude at all, whereas other launch directions would typically either degrade the aerodynamics of platform110B or risk tangling suspension lines within the pusher rotor, for example, and typically result in platform110B traveling 5 or more body lengths before slowing. In situations where platform110B is experiencing a navigation crisis that involves a dive (e.g., where its rotor is aligned substantially vertically), the concerns and benefits illustrated with respect to platform110A apply.

FIG.3Aillustrates a diagram of UAV rescue parachute deployment system160in accordance with an embodiment of the disclosure. InFIG.3A, RPDS160includes canopy assembly168, capsule rotor guard366, and ejector assembly164all secured to each other via a shock cord370, as shown. In various embodiments, regulations pursuant to UAV flight over people may require that no element of RPDS160become loose or free fall during deployment and descent. In such embodiments, shock cord370may be coupled to suspension lines of canopy368, through all elements of rotor guard166, and to ejector assembly164(e.g., or potentially through ejector assembly164directly to platform110and/or payload140) to ensure no elements of RPDS160free fall after deployment of canopy assembly168.

In the embodiment shown inFIG.3A, rotor guard366is implemented as a capsule including a tapered rotor guard body or cup380, a vent hole seal member384(e.g., configured to seal vent holes disposed in a base of capsule body380against ambient water ingress into rotor guard366), and a dome shaped lid382, each of which may be coupled to shock cord370such as by threading shock cord370through corresponding shock cord orifices and/or knotting shock cord370(e.g., to itself or retainer features integrated with the various elements) to limit movement of the various elements along a length of shock cord370. In some embodiments, RPDS may include a safety flag and/or shock cord coupler374disposed adjacent ejector assembly164and configured to confirm readiness of RPDS160when RPDS is coupled to platform110.

FIG.3Billustrates a diagram of UAV rescue parachute deployment system160in accordance with an embodiment of the disclosure. In particular,FIG.3Bshows a simulated deployment state of RPDS360just before unfurling and inflation of canopy assembly168after RPDS is launched vertically by ejector assembly164. Alternatively,FIG.3Bshows a prepacking state of RPDS360after a portion of shock cord370has been wrapped about canopy368to help form canopy assembly168and after vent hole seal member384has been depressed into capsule body380and/or adjacent to an internal surface of a base of capsule body380, prior to packing canopy assembly168and portions of shock cord370within capsule body380and attaching dome shaped lid382to capsule body380to enclose canopy assembly168within rotor guard366.

FIG.3Cillustrates a diagram of ejector assembly164for UAV rescue parachute deployment system160in accordance with an embodiment of the disclosure. As shown inFIG.3C, ejector assembly164may be implemented by a cylindrical launch canister350configured to provide structural support and/or housing for the various elements of ejector assembly164, for example, and to provide impulse leverage between one or more impulse generators354and a launch platform or plunger352. For example, in the embodiment depicted byFIG.3C, impulse generators354are implemented by a plurality of impulse linkages or pull-springs (e.g., elastic bands) each fixed adjacent a base of launch canister350, looped through a lip of launch canister350, and secured to a one of a plurality of launch impulse interfaces356of launch platform352.

In such embodiments, launch platform352may be depressed into launch canister350- to reposition launch impulse interfaces356from proximate a lip of launch canister350, along interface guides/slots358, to proximate a base of launch canister350, in order to stretch impulse linkages354(e.g., to prime impulse generators354). Launch platform352and/or launch impulse interfaces356may then be secured to an actuated launch release357of launch canister350to place ejector assembly164in a primed state (ejector assembly164is in an unprimed or expended state otherwise). After canopy assembly168and rotor guard166are secured within a primed ejector assembly168, RPDS160is in a primed state (RPDS160is in an unprimed or expended state otherwise). Once primed, RPDS160may deploy or launch canopy assembly168and rotor guard166by releasing actuated launch release357, which causes launch platform352and/or launch impulse interfaces356to return to the lip of launch consider350and provide sufficient momentum to rotor guard160and canopy assembly168to launch and deploy canopy assembly through a rotor plane of platform110reliably and safely.

In alternative embodiments, impulse generator(s)354may be implemented by push springs disposed within launch canister350and between a base of launch canister350and an underside of launch platform352. In still further embodiments, impulse generator(s)354may be implemented by compressed gas capsules and/or other impulse generators configured to elevate launch platform352from a primed position adjacent the base of launch canister350towards a lip of launch canister350. In various embodiments, launch canister350may also provide structural support and/or housing for deployment controller162, external memory interface362, wired communications interface361, and/or any other elements of RPDS160(e.g., including other modules170), which may be disposed adjacent to and/or integrated with a base of launch canister350, as shown.

FIGS.4A-7Cillustrate various structurally differentiated embodiments of rotor guard166. In particular,FIGS.4A-5Cdepict embodiments of capsule-shaped rotor guards (e.g., rotor guards466and566), andFIG.6-7Cdepict embodiments of rotor guard frames (e.g., rotor guard666). Each rotor guard embodiment was filmed using a high speed camera (e.g., 2000fps) during deployment through a rotor plane under variable conditions, including stationary rotors with blades disposed directly above launch canister350and impeding deployment of canopy assembly168, residually rotating rotors (e.g., rotating at approximately 200 rpm, which is typical when rotors are deenergized just before deploying canopy assembly168), and fully powered rotating rotors (e.g., rotating at approximately 3000 RPM, which can happen if deployment of canopy assembly168occurs without deenergizing the rotor beforehand). Under all conditions, all rotor blade hits were absorbed by the various embodiments of rotor guard166, and canopy assembly168was undamaged and able to unfold and inflate.

FIGS.4A-Billustrate diagrams of a capsule-shaped rotor guard466for UAV rescue parachute deployment system160in accordance with embodiments of the disclosure. In some embodiments, rotor guard466may be implemented similar to and/or share features of capsule-shaped rotor guard366ofFIGS.3A-B. In particular, rotor guard466may be implemented as a relatively rigid capsule including: vent holes for vacuum relief during parachute deployment; various ribs and/or other features to space and/or align rotor guard466from/to launch canister350(e.g., to protect from ice formation in narrow gaps); a tapered body shape for reliable rotor guard ejection/launch; and one or more beads of silicon grease to seal rotor guard466from water ingress, as described herein. In general, capsule-shaped rotor guard466may be deployed by ejector assembly164via launch platform352engaging with a base of rotor guard466and forcing rotor guard466out of launch canister350as launch platform352is elevated away from the base of launch canister350and towards a lip of launch canister350(e.g., by impulse generator354).

As shown inFIG.4A, capsule-shaped rotor guard466may be implemented by a tapered cylindrical rotor guard body480and a dome shaped lid482configured to couple to rotor guard body480and form capsule-shaped rotor guard466. Rotor guard body480may include spacer ribs486distributed about a cylindrical wall of rotor guard body480to provide spacing from and/or alignment with an interior of launch canister350, for example, and/or arcuate spacer ribs487distributed about a base edge of rotor guard body480to provide spacing from and/or alignment with a base and/or orientation of launch canister350. In some embodiments, rotor guard body480may include one or more vent holes484in the base of rotor guard body480to provide air ingress into rotor guard body480and/or rotor guard466(e.g., to provide vacuum relief to the interior of the capsule) and to allow dome shaped lid482and/or canopy assembly168to escape rotor guard body480during deployment of canopy assembly168. In related embodiments, rotor guard body480may include a shock cord orifice485in the base of rotor guard body480that is configured to pass through at least a portion of shock cord370and secure rotor guard body480to shock cord370to prevent it from becoming decoupled from platform110after deployment of canopy assembly168. A similar shock cord orifice may be formed at the apex of dome shaped lid482. As part of assembly of rotor guard466, and after dome shaped lid482is engaged with rotor guard body480(e.g., to encapsulate canopy assembly168), a silicon grease bead488may be formed about the seam between dome shaped lid482and rotor guard body480to seal rotor guard466against moisture ingress, as shown.

FIG.5Aillustrates a diagram of a capsule-shaped rotor guard566for UAV rescue parachute deployment system160in accordance with an embodiment of the disclosure. In particular, rotor guard566may be implemented as a relatively rigid capsule including interlocking halves with a vertical parting line and a shock cord orifice for shock cord370and/or an associated parachute harness disposed along the vertical parting line, as shown. Rotor guard566may also include any of the various elements and/or characteristics described with reference to capsule shaped rotor guard466ofFIGS.4A-B.

As shown inFIG.5A, capsule-shaped rotor guard566may be implemented by first and second cylindrical domed half-shell bodies580and582configured to interlock with each other to form capsule-shaped rotor guard566. In various embodiments, each domed half-shell body580and582may include one or more shell body interlocks584configured to secure the half-cylindrical body portions of each domed half-shell body to each other, and a base lip586disposed along a base edge of the domed half-shell body. Each base lip586may include a base interlock disposed at either end that is configured to interlock the bases and/or base lips of each domed half-shell body to each other, as shown. In addition, each base lip586may include one or more base lip supports/angles587configured to provide structural rigidity to each base lip586. Such base lip supports/angles587may also provide for formation of various alignment features for alignment within launch canister350and/or to launch platform352, as described herein. In the embodiment presented byFIG.5A, each domed half-shell body580and582includes a portion of a shock cord orifice588disposed along the vertical split-shell seam between the two bodies and substantially above or adjoining a top of shell body interlocks584.

FIGS.5B-Cillustrate diagrams of rotor guard566ofFIG.5Adisposed about a canopy assembly168for UAV rescue parachute deployment system160in accordance with embodiments of the disclosure. In particular,FIGS.5B-Cillustrate two assembly states502and504in preparation of loading rotor guard566into a primed or unprimed ejector assembly168. In assembly state502ofFIG.5B, canopy368is folded, wrapped, and/or rolled together with suspension lines369to form canopy assembly168, which is placed within one domed half-shell body580, and shock cord370is fed through shock cord orifice588. In assembly state504ofFIG.5C, domed half-shell body582is interlocked with domed half-shell body580to enclose/encapsulate canopy assembly168with shock cord370extending through shock cord orifice588, which is disposed along split-shell seam581as shown. In some embodiments, rotor guard566may include one or more alignment features/notches587(e.g., corresponding to base lip supports/angles587shown inFIG.5A) configured to rotationally align rotor guard566within launch canister350(e.g., to ensure shock cord orifice588and/or shock cord370is disposed at a desired position relative to platform110and/or RPDS coupler128when RPDS160is in a primed state/during flight of platform110). In various embodiments, when assembled, rotor guard566may be capsule shaped with a tapered body (e.g., narrower at a base of rotor guard566), similar to rotor guard466ofFIGS.4A-B.

FIG.6Aillustrates a diagram of a rotor guard frame666for UAV rescue parachute deployment system160in accordance with an embodiment of the disclosure. In particular, rotor guard666may be implemented as a relatively rigid outer guard frame structure including several pushrods each coupled to corresponding launch impulse interfaces356of launch platform352, for example, and coupled to each other via a ring frame. During deployment of canopy assembly168, the pushrods and ring frame move together with launch impulse interfaces356of launch platform352. The pushrods can absorb rotor impacts, particularly when structurally stabilized by the ring frame, which may be coupled to and disposed near the top of the pushrods to form the rigid outer guard frame structure. The arrangement of ring frame and pushrods provides structural rigidity and prevents rotor guard666from bending and jamming during deployment and/or possible rotor impacts during deployment. Rotor guard666may in some embodiments include various elements and/or characteristics described with reference to capsule shaped rotor guards466and/or566ofFIGS.4A-5C.

As shown inFIG.6A, rotor guard frame666may be implemented by a plurality of pushrods680(e.g., rotor guard rods) coupled together by a ring frame682to form a roughly tapered cylindrical rotor guard frame, as shown. Such rotor guard frame may be sized to encompass and/or be disposed about canopy assembly168, also as shown. In some embodiments, each pushrod680may include an ejector assembly interface686disposed at a lower end and configured to engage with launch impulse interfaces356and/or launch platform352and elevate rotor guard frame666out of launch canister350during deployment of canopy assembly168. Each pushrod680may also be sized to have a length greater than a height of canopy assembly168(as bundled for insertion into ejector assembly164), such that the top of each pushrod680extends above a top surface of ring frame682. In general, the number and arrangement (e.g., relative positioning) of pushrods680within ring frame682may be determined based on the expected rotor impact points along a periphery of rotor guard666and/or canopy assembly168during flight of platform110, for example, so as to limit the weight of rotor guard666. In some embodiments, such relative positioning (e.g., relative to the expected rotor impact points) may be ensured by rotationally aligning rotor guard666within ejector assembly164via one or more alignment features/notches687formed along an outer edge of ring frame682.

In various embodiments, each pushrod680may be glued, welded, and/or otherwise affixed to ring frame682disposed about a circumference of ring frame682and oriented roughly parallel to a symmetry axis of ring frame682, such as to form a cylindrical rotor guard frame, for example, which may in some embodiments be tapered at its base to facilitate loading and launching of rotor guard666and canopy assembly168. In some embodiments, each pushrod680may be affixed within holes formed through and roughly perpendicular to a characteristic plane of ring frame682(e.g., a characteristic plane perpendicular to the central symmetry axis of ring frame682). In some embodiments, ring frame682may be roughly toroidal, for example, and may include a rectangular or square cross section, as shown inFIG.6A.

FIGS.6B-Dillustrate diagrams of UAV rescue parachute deployment system160employing rotor guard666ofFIG.6A, in accordance with embodiments of the disclosure. In particular,FIGS.6B-Dillustrate three assembly states602,604, and606associated with loading rotor guard666into ejector assembly168and/or priming ejector assembly168and/or RPDS160. In assembly state602ofFIG.6B, canopy368is folded, wrapped, and/or rolled together with suspension lines369to form canopy assembly168, which may be placed within and/or include a tapered canopy shroud668(e.g., a tapered open cylinder of plastic wrapping film), and fed into rotor guard666such that canopy assembly168and/or canopy shroud668contacts an inner surface of ring frame682(e.g., which may prevent canopy assembly168and/or canopy shroud668from unraveling during loading into ejector assembly164). Each ejector assembly interface686of pushrods680may be positioned to engage with corresponding launch impulse interfaces386, and shock cord370may be wrapped within and/or draped off to the side of canopy assembly168, as shown.

In assembly state604ofFIG.6C, rotor guard666is inserted into ejector assembly164such that launch platform350and launch impulse interfaces386are depressed into launch canister350by pushrods680via ejector assembly interface686of pushrods680. In assembly state606ofFIG.6C, rotor guard666is fully loaded into ejector assembly164such that launch platform350and/or launch impulse interfaces386are engaged with actuated launch release357of launch canister350, ejector assembly164is in a primed state, and RPDS160is in a primed state. In some embodiments, ring frame682may be adjoining a top lip of launch canister350when RPDS160is in such primed state, as shown.

FIGS.6E-Fillustrate diagrams of UAV rescue parachute deployment system160employing rotor guard666ofFIG.6A, as installed on UAV110, in accordance with embodiments of the disclosure. In particular,FIGS.6E-Fillustrate two deployment states608and612associated with deploying rotor guard666and canopy assembly168by ejector assembly168through a rotor plane of platform110. In deployment state608ofFIG.6E, canopy assembly168and rotor guard666(e.g., pushrods680and ring frame682) of RPDS160are partially deployed into a rotor frame of platform110. Ejector assembly164of RPDS160is coupled to airframe610of platform110via RPDS coupler128(e.g., a slide and slot coupler mechanism), and rotor guard666is rotationally aligned within ejector assembly164and/or relative to an orientation of airframe610of platform110via ejection assembly alignment latch664configured to fit within and/or align with alignment notch687formed in ring frame682of ring guard666.

As can be seen inFIG.6E, ring frame682is just below rotor blades624, and rotor blades624are impacting pushrods680at rotor impact points698and699. As such, pushrods680have been positioned to absorb rotor impacts without allowing rotor blades624to contact canopy assembly168(e.g., while rotor blades624are rotating in their expected directions). Shock cord370is draped out of view for illustrative purposes but is shown attached both to canopy assembly168and airframe610of platform110. In deployment state612ofFIG.6F, canopy assembly168and rotor guard666(e.g., pushrods680and ring frame682) of RPDS160are fully deployed into a rotor frame of platform110, such that contact point699between rotor blade624and pushrod680is below ring frame682, and canopy assembly168is protected from rotor impacts as it is deployed through the rotor plane of platform110.

As can be seen fromFIGS.6A-F, canopy assembly168is not packed into a sealed container. In some embodiments, RPDS160may be protected from water ingress and UV radiation by a single-use weather pouch configured to enclose and seal at least a portion of RPDS160against such environmental conditions. For example, the tops of pushrods680of rotor guard666may be configured to tear through, open, and/or otherwise unseal the weather pouch during deployment of rotor guard666and provide an egress for the deployment of canopy assembly168through the rotor plane of UAV/platform110.

FIGS.7A-Cillustrate diagrams of UAV rescue parachute deployment system160utilizing a weather pouch to protect elements of RPDS160from environmental conditions in accordance with an embodiment of the disclosure. In particular,FIGS.7A-Cillustrate three operational states702,704, and706associated with packaging rotor guard666and canopy assembly168within a weather pouch and deploying rotor guard666and canopy assembly168via RPDS160. In operational state702ofFIG.7A, primed RPDS760with pushrods680of rotor guard666extending from a top of RPDS760is positioned adjacent to an unsealed and open weather pouch762. In various embodiments, weather pouch762may be single use or disposable, for example, and may be formed from a relatively thin strong and flexible material, such as metallized mylar with an integrated thermal seal layer, for example, or other polymeric material films, such as vapor metalized polyethylene terephthalate (PET) films - MPET/PET.

In operational state704ofFIG.7B, primed RPDS760placed and sealed within weather pouch762such that shock cord370extends from the sealed end of weather pouch762. In such operational state, primed RPDS760may be coupled to platform110via RPDS coupler128without breaking the seal of weather pouch762through use of a slide and slot latching mechanism that allows the relatively thin wall of weather pouch762to conform to and/or integrate with the slide and slot latching mechanism (e.g., as shown inFIG.6E). Shock cord370may be coupled to RPDS coupler128, for example, or elsewhere to airframe610of platform110.

In operational state706ofFIG.7C, RPDS160has deployed canopy assembly168and rotor guard666, where tops of pushrods680of rotor guard666have torn, opened, or otherwise unsealed weather pouch762and launched canopy assembly168out of weather pouch762through a rotor plane of platform110, as described herein. In some embodiments, rotor guard666may be configured to elevate and stop with launch impulse interfaces356and/or launch platform350due to ejector assembly interfaces686of pushrods680being securely coupled to launch impulse interfaces356, as shown inFIGS.6B-D. After launch impulse interfaces356and/or launch platform350reach the end of their elevation travel, canopy assembly168may continue along its launch motion due to the momentum imparted to it by ejector assembly164, as described herein.

FIG.8illustrates a flow diagram800of various operations to operate UAV rescue parachute deployment system160in accordance with an embodiment of the disclosure. In some embodiments, the operations ofFIG.8may be implemented as software instructions executed by one or more logic devices or controllers associated with corresponding electronic devices, sensors, and/or structures depicted inFIG.1-7C. More generally, the operations ofFIG.8may be implemented with any combination of software instructions, mechanical elements, and/or electronic hardware (e.g., inductors, capacitors, amplifiers, actuators, or other analog and/or digital components). Any step, sub-step, sub-process, or block of process800may be performed in an order or arrangement different from the embodiment illustrated byFIG.8. For example, in other embodiments, one or more blocks may be omitted from or added to process800. Furthermore, block inputs, block outputs, various sensor signals, sensor information, calibration parameters, and/or other operational parameters may be stored to one or more memories prior to moving to a following portion of a corresponding process. Although process800is described with reference to systems described inFIG.1-7C, process800may be performed by other systems different from those systems and including a different selection of electronic devices, sensors, assemblies, mechanisms, platforms, and/or platform attributes.

At block802, control signals associated with an RPDS are received. For example, controller112, deployment controller162, and/or communications module120may be configured to receive control signals associated with RPDS160, such as control signals generated by controller112, user interface132, and/or communication module132. In some embodiments, such control signals may include an RPDS arm signal, for example, where RPDS160is disabled until such RPDS arm signal is received and/or generated by one or more elements of system100. Such control signals may also include a rescue parachute launch signal generated by UAV110and/or base station130, for example, such as after detection of a navigation crisis, as described herein, or affirmatively via user input provided to user interface132of base station130(e.g., a user manual deployment signal or a mission abort signal). In additional embodiments, such control signals may include a payload release signal generated by UAV110and/or base station130, for example, such as after determining UAV110has reached a delivery location, as described herein, or affirmatively via user input provided to user interface132of base station130(e.g., a payload drop signal).

At block804, telemetry data associated with a UAV is received. For example, controller112, deployment controller162, and/or communications module120may be configured to receive telemetry data associated with RPDS160and/or UAV110from one or more telemetry sensors coupled to and/or integrated with RPDS160and/or UAV110. In various embodiments, such telemetry sensors may include any of the orientation, position, motion, imagery, environmental, and/or other navigational sensors coupled to and/or integrated with elements of system100, for example, and such telemetry data may include their associated sensor data, as described herein.

In block806, a rescue parachute launch condition is determined as active. For example, controller112and/or deployment controller162may be configured to determine a rescue parachute launch condition is active based, at least in part, on the control signals and/or telemetry data received in blocks802and/or804. In one embodiment, controller112and/or deployment controller162may be configured to determine a rescue parachute launch condition is active when a UAV navigation crisis exists. For example, controller112and/or deployment controller162may be configured to determine a navigation crisis exists based, at least in part, on the telemetry data received in block804.

Such UAV navigation crisis may include one or more of: unintended inverted flying of UAV110, attitude excursions of UAV110outside preselected safety attitude ranges (e.g., maximum attitude angles and/or angle rates — such as entering unrecoverable pitches or rolls/tilts — supplied as user input to base station130prior to mission deployment), unintended and/or otherwise unrecoverable losses of altitude of UAV110(e.g., where the rate of loss of altitude exceeds the maneuvering capability of propulsion system124and/or UAV110), entrance of UAV110into a restricted altitude or airspace (e.g., related to geo-fencing and/or public safety, such as regulatory unmanned flight restrictions associated with airports), loss of propulsion or navigation control power for UAV110, free fall of UAV110, loss of communication between UAV110and base station130associated with UAV110, and/or other use-case or application specific telemetry events. Such application specific telemetry events may include failure of UAV110to reach a designated location at a designated time, failure of UAV110to traverse a designated route or portion of a designated route within a designated time period, detection of a particular environmental condition (e.g., precipitation) about UAV110, environmental conditions about UAV110exceeding a maneuvering capability of UAV110, physical damage to propulsion system124and/or UAV110, and/or proximity of UAV110to a static or mobile structure (e.g., a building or another manned or unmanned aircraft), for example.

In another embodiment, controller112and/or deployment controller162may be configured to determine a rescue parachute launch condition is active when a rescue parachute launch signal and/or a payload release signal (e.g., when shock cord370is coupled to payload140of UAV110) is generated and/or received, as described herein.

In block808, a canopy assembly is deployed through a rotor plane of a UAV. For example, controller112and/or deployment controller162may be configured to control actuated launch release357integrated with ejector assembly164of RPDS160to deploy rotor guard166into and canopy assembly168through a rotor plane of UAV110by releasing launch platform350and/or launch impulse interfaces356and/or activating impulse generator(s)354to generate a launch impulse to deploy rotor guard166and canopy assembly168, as described herein.

In some embodiments, controller112and/or deployment controller162may be configured to generate and/or provide a control signal to propulsion system124of UAV110to deenergize propulsion system124before launching/deploying rotor guard160and canopy assembly168. In related embodiments, controller112and/or deployment controller162may be configured to generate and/or provide a control signal to propulsion system124to stop and/or brake all rotors powered by and/or otherwise associated with propulsion system124. In other embodiments, controller112and/or deployment controller162may be configured to control a payload coupler of UAV110(e.g., an embodiment of gimbal system122) to release payload140from UAV110prior to controlling ejector assembly164to deploy canopy assembly168through the rotor plane of UAV110, as described herein.

In additional embodiments, before, during, or after deploying rotor guard160and canopy assembly168, system100may be configured to sound/energize an audio alarm, which may be coupled to UAV110and/or RPDS160(e.g., other modules126and/or170) and/or integrated with base station130(e.g., user interface132and/or other modules136), for example, and/or to light and/or flash safety LEDs mounted to UAV110and/or RPDS160(e.g., other modules126and/or170) and/or integrated with base station130(e.g., user interface132and/or other modules136).

In some embodiments, controller112and/or deployment controller162may be configured to detect that UAV110is inverted (e.g., pitch and/or roll less than negative ninety [-90] degrees) and either delay deployment of rotor guard166and/or canopy assembly168until UAV is not inverted (e.g., pitch and/or roll equal to or greater than negative ninety [-90] degrees), for example, or control propulsion system124to attempt to right UAV110, prior to reaching a minimum deployment altitude, under which rotor guard166and/or canopy assembly168will be deployed regardless of an inverted/non-inverted state of UAV110.

By providing such systems and techniques for UAV rescue parachute deployment, embodiments of the present disclosure substantially improve the operational flexibility and reliability of unmanned flight platforms. Moreover, such systems and techniques may be used to increase the operational safety of unmanned flight platforms beyond that achievable by conventional systems. As such, embodiments provide UAV rescue parachute deployment systems with significantly increased convenience and performance.