Aircraft with distributed power system, distributed control system, and safe deployment mechanism for ballistic recovery system

An electric aircraft comprises a single passenger seat, vertical takeoff and landing capable rotorcraft with an amphibious undercarriage for ground or water landing and takeoff. An electrical power system includes an independent battery for each motor with quick-swap mechanism to enable drained batteries to be easily removed for external charging and swapped for a charged replacement battery. A ballistic recovery system may be deployed to safely land the aircraft in the event of an emergency and may be manually deployed in response to the passenger activating a deployment mechanism integrated into handles within the cockpit. An on-board flight control system includes an automated flight controller that places constraints on flight maneuvers, and a manual flight controller provides a passenger with a limited level of control over the flight.

BACKGROUND

Ultralight aircrafts are a class of aerial vehicles that meet certain weight specifications defined by the various jurisdictions in which they operate. For example, in the United States, an ultralight aircraft is defined as an aircraft weighing less than 254 lbs., with some extra weight allowed for amphibious landing gear and ballistic parachute systems. Obtaining ultralight aircraft classification is desirable because in most jurisdictions, it enables operation without limited or no licensing requirements. However, a challenge exists in ensuring that an ultralight aircraft has adequate safety features while still meeting the weight requirements.

SUMMARY

An electric aircraft includes an undercarriage, a cockpit, a canopy, and on-board electronic flight controller. The undercarriage comprises a plurality of floats enabling floatation of the electric aircraft. The cockpit is over the undercarriage and includes a seat for securing a passenger within the electric aircraft and a windshield at least partially enclosing the cockpit. The canopy is over the cockpit and comprises a structural frame and a plurality of distributed lifting devices. The plurality of distributed lifting devices each include a rotor to provide lift to the electric aircraft, a motor to drive rotation of the rotor, and a battery pack to supply power to the motor. The on-board electronic flight control system controls the distributed lifting devices in response to flight controls to carry out a flight of the electric aircraft.

In an embodiment, the battery pack provides power to one and only one motor. Furthermore, in an embodiment, the battery pack includes a first quick-swap mechanism for securely mating to a reciprocally structured second quick-swap mechanism of a terminal positioned on a portion of the structural frame below the motor. The first quick-swap mechanism may comprise a set of cylindrical tenon studs on the battery pack that mate with corresponding keyhole slots of the terminal. Furthermore, a first electrical connector on the battery pack mates with a second electrical connector of the terminal to establish an electrical connection when the first quick-swap mechanism of the battery pack is secured to the second quick-swap mechanism of the terminal. A safe lock mechanism may include a pin insertable through a respective pin sleeve on the battery pack and the terminal that are aligned when the first quick-swap mechanism of the battery pack is secured to the second quick-swap mechanism of the terminal.

In an embodiment, the plurality of floats comprises a central float directly under the cockpit, and four side floats distributed around the central float. In an alternative embodiment, the plurality of floats comprises a central float directly under the cockpit, and six side floats distributed around the central float.

In an embodiment, the electric aircraft further comprises a ballistic recovery system for landing the electric aircraft in an emergency event. The ballistic recovery system includes a parachute deployable from a compartment on the canopy, and a deployment mechanism for causing the parachute to deploy. The deployment mechanism comprises a pair of push buttons positioned on respective handles within the cockpit proximate to opposite edges of the windshield. The deployment mechanism to deploy the parachute in response to the push buttons being concurrently activated for at least a predefined time period. In an embodiment, the on-board electronic flight control system is configured to disconnect power to the motors in response to deployment of the parachute.

In an embodiment, the electric aircraft further comprises triple redundant on-board sensors for sensing data relevant to the flight. The triple redundant sensors include a primary sensor and two or more backup sensors that activate in response to failure of the primary sensor.

In an embodiment, the on-board electronic flight control system comprises an autonomous flight controller to automatically control at least a first aspect of the flight of the electric aircraft in accordance with a predefined flight plan, and a manual flight controller to enable the passenger to provide manual control inputs to control at least a second aspect of the flight. Here, the autonomous flight controller may automatically impose a set of constraints on the flight in accordance with the predefined flight plan, and the manual flight controller enables the passenger to control the flight within the set of constraints imposed by the autonomous flight controller. In an embodiment, the autonomous flight controller automatically imposes the set of constraints by performing at least one of the following actions: controlling the electric aircraft to maintain a position within a predefined geographic region; controlling the electric aircraft to avoid a collision; controlling the electric aircraft to avoid entering a geographic area having over a threshold level of congestion; controlling the electric aircraft to land according to a set of predefined landing maneuvers; controlling the electric aircraft to initiate landing in response to predefined landing criteria; controlling the electric aircraft to takeoff according to a set of predefined landing maneuvers; and controlling the electric aircraft to initiate takeoff in response to takeoff criteria.

DETAILED DESCRIPTION

The figures and the following description relate to embodiments by way of illustration only. From the following discussion, alternative embodiments of the structures and methods disclosed herein will be readily recognized as viable alternatives that may be employed without departing from the principles of the disclosure.

FIGS. 1-3illustrate an isometric view, a front view, and a side view respectively of a passenger-carrying aircraft100. The aircraft100may comprise a single passenger seat, vertical takeoff and landing capable rotorcraft with an amphibious undercarriage for ground or water landing and takeoff. In an embodiment, the aircraft100meets the qualification for ultralight aircraft classification in at least the United States. The aircraft100includes a canopy1including a cockpit with a single passenger seat and a windshield. The aircraft100can be piloted by the on-board passenger using an on-board joystick, by a ground controller via radio link to the aircraft100, by an autonomous flying system (e.g., to autonomously fly a preset route), or by a combination thereof controlling a fully electronic flight control system. A structural frame2comprises a semi-open structure above the cockpit with18independent, electrically powered lifting devices. The structural frame2may comprise a carbon composite structural frame or other suitable material that is sufficiently strong and lightweight. The lifting devices each include a rotor3, a motor4, and a battery pack5. The motors4may comprise, for example, brushless DC motors that drive respective direct-drive rotors3using power provided by the attached battery packs5. The electrical power system includes an independent battery5for each motor4with quick-swap mechanism to enable drained batteries5to be easily removed for external charging and swapped for a charged replacement battery5, as will be described in further detail below. The cockpit rests on an amphibious undercarriage consisting of one central float7and six side floats6that enable the aircraft to float on water. In alternative embodiments, a different number of floats6may be used (e.g., a central float7and four side floats6). The aircraft100is also equipped with a ballistic recovery system8that may be deployed to safely land the aircraft100in the event of an emergency (e.g., loss of lift or flight control). For example, the ballistic recovery system8may comprise a parachute that deploys from a compartment in the top of a central portion of the frame2above the cockpit. The ballistic recovery system8may be manually deployed in response to the passenger activating a deployment mechanism integrated into handles9within the cockpit as will be described in further detail below.

The architecture of the aircraft100utilizes 18 relatively small rotors3to provide lift, which beneficially improves stability and safety relative to other aircrafts that instead employ a smaller number of larger rotors. In this distributed propulsion system, a relatively small amount of available thrust is lost in the event of single failure of a motor4or rotor3. Furthermore, the distributed power system that includes an independent battery5for each motor4and rotor3limits loss of thrust to a single rotor3in the event of a single battery failure. Furthermore, the loss of a single battery5at most minimally impacts the power drain demand on the remaining batteries. Additionally, the placement of each battery5directly adjacent to the motor4that it drives eliminates the need for high amperage power lines from a centralized battery and eliminates the possibility of a central power line failure that could completely shut down the aircraft100. Further still, the distributed battery system reduces overall wiring and power distribution systems typically employed in centralized battery systems, thereby reducing the relative weight of the aircraft100.

In an embodiment, an on-board electronic flight control system810(shown inFIG. 8) controls the motors4to drive the rotors3of the aircraft100in response to a flight control inputs816(which may be provided manually by a passenger in the aircraft100, by ground control personnel, by an autonomous flight system814, or a combination thereof) in order to carry out the intended flight path and achieve sufficient stability. For example, the electronic flight control system810may comprise a fly-by-wire system that automatically determines, independently for each motor4, an amount of power to apply to each motor4that will appropriately control a rotation speed of a connected rotor3to ensure stable flight while carrying out the desired flight path. The electronic flight control system810may comprise various sensors820integrated with the aircraft100to provide feedback to the electronic flight control system810relating to environmental conditions and a real-time state of the aircraft100. For example, sensors820may include an inertial measurement unit (IMU) that may include an accelerometer, gyroscope, or other motion sensor to track motion of the aircraft100, environmental sensors such as temperature sensors, pressure sensors, wind sensors, rain sensors, etc., cameras that capture image data of the aircraft100or surrounding environment, or other sensors useful to determine how to control the rotors3to achieve the desired flight and stability. For example, the aircraft100may automatically adjust based on detected wind speed or other factors. The aircraft100may include redundant sensors820(e.g., triple redundant sensors) such that backup sensors may be employed in the event that a primary sensor fails. In an embodiment, a backup sensor may be automatically activated in response to failure of the primary sensor.

In an embodiment, the on-board electronic flight control system810includes a processor and a non-transitory computer-readable storage medium storing instructions that when executed cause the on-board flight control system810to carry out the functions described herein. The on-board flight control system810may furthermore include a wireless communication system to enable the on-board flight control system to communicate with a ground control system. For example, the wireless communication system may enable flight control signals to be transmitted from a ground control system to the on-board electronic flight control system810and may enable sensor data or other telemetry data to be communicated to the ground control system. Furthermore, the wireless communication system may enable voice communications to be transmitted between the on-board electronic flight control system810and the ground control system to enable a passenger to communicate with ground control personnel.

In an embodiment, the on-board electronic flight control system810comprises an autonomous flight controller814to automatically control at least a first aspect of the flight of the electric aircraft100in accordance with a predefined flight plan, and a manual flight controller812to enable the passenger to provide manual control inputs to control at least a second aspect of the flight.

In an embodiment, the automated flight system814may have full control of the flight of the aircraft100, for example, to execute a pre-planned flight path. Alternatively, the automated flight system814may augment manual control inputs (e.g., provided by the passenger via a control joystick, a voice command, or other input) to enable the passenger to have a level of control of the aircraft while enforcing certain constraints. For example, in an embodiment, the flight control system810may generally control the aircraft100according to manual inputs from the passenger if they meet certain flight constraints, but the autonomous flight system814may prevent the aircraft from leaving a certain predefined geographic boundary (e.g., defining a three-dimensional volume) or taking other disallowed actions (e.g., exceeding predefined maximum speed, exceeding a maximum bank angle, etc.). For example, the autonomous flight control system814may override manual inputs that may be violate one of the constraints. In another example, the autonomous flight system814may take automatic action to avoid collisions with other objects that are detected based on the sensor data or that are at known fixed locations. Here, the flight control system814may override manual flight control inputs when appropriate to avoid such collisions. In yet another example, the flight control system814may detect congested areas in which a significant number of other aircrafts are present (e.g., based on ground telemetry data), and prevent the aircraft100from entering those congested areas, overriding manual controls when appropriate. In another example, the passenger may interact with the flight control system814to cause the aircraft100to take certain actions by autonomous control. For example, the passenger may request (via voice control or other control input) that the aircraft100automatically takeoff or land, and the flight control system814may implement the takeoff or landing automatically without the passenger manually controlling the aircraft100through these maneuvers. In another example, the passenger may provide a voice command or other control input to cause the aircraft to ascend or descend to a particular requested altitude or navigate to a particular requested geographic location. Furthermore, the flight control system814may automatically control the aircraft to return to a designated safe location in response to detecting that the batteries5are running low.

In an embodiment, a ground flight controller may also be present that may transmit control signals to control flight of the electric aircraft100using teleoperation. In an embodiment, the ground flight controller may override manual controls performed by a passenger in the electric aircraft. Furthermore, the ground flight controller may override the on-board autonomous flight controller814, and thus may cause the electric aircraft100to take actions that may otherwise violate constraints set by the autonomous flight controller814. In this manner, a human ground controller may optionally take control of the aircraft100(e.g., in case of an emergency or failure of the autonomous flight controller).

In an embodiment, the flight control system810is triple redundant. In this case, if the primary flight control system fails, one of the backup systems can seamlessly take over.

Distributed Battery System

FIGS. 4-6illustrates an example embodiment of a distributed power system for the aircraft100. Particularly,FIG. 4illustrates an example embodiment of a battery pack5,FIG. 5illustrates an example embodiment of a terminal18of the structural frame2connected to the motor4for connecting to a battery pack5, andFIG. 6illustrates an alignment between a battery pack5and the terminal18for connecting or disconnecting a battery5according to a quick-swap mechanism. Power lines between the terminal18of the structural frame2and the motor4provide a power connection between the terminal18and the motor4to drive the motor4when the battery5is connected to the terminal18.

In the distributed battery system, each battery5connects to and provides power to only a single motor4. Thus, the maximum power that is to be transmitted by electric wires within the frame2between the terminal18and the motor4are relatively low compared to an aircraft using a centralized battery system with high power lines. In the aircraft100, the power lines between the batteries5and the motors4may be relatively thinner wires, operate at relative lower temperatures, and operate with bottleneck-free power routing. Furthermore, due to the low power transfer demand, an embodiment of the aircraft100does not include switches, relays, or fuses in the power distribution system to reduce weight and failure points.

The battery packs5are each removable from the aircraft100and can be charged externally, beneficially eliminating the need for a charging system integrated into the aircraft100and reducing overall weight, complexity, and points of failure. Furthermore, the removable battery system enables batteries5to be quickly swapped out for charged batteries, thus avoiding having to ground the aircraft100while the batteries5recharge.

Each battery5includes a quick-swap securing mechanism that enables a battery5to be quickly attached and detached from the aircraft100so that depleted batteries5can be removed and swapped for charged batteries5. In an embodiment, the quick-swap mechanism includes a set of cylindrical tenon studs10(e.g., three studs10) on the battery5, that fit into corresponding keyhole slots14of the terminal18of the structural frame2below the motor4. To install a battery5, the battery5is positioned to align the studs10with the slots14as illustrated inFIG. 6. The studs are 10 initially slid upward into the large portions of the slots14. In this position, the electronic connector11of the battery5and the reciprocal electronic connector13of the motor4are not yet connected. The keyhole shape of the slots14allows for only one horizontal degree of freedom, which enables the battery5to be moved (e.g., approximately one-half inch) horizontally towards the center of the terminal18. The studs10keep the battery5in the appropriate vertical position while being slid horizontally to ensure proper alignment between the respective connectors11,13. Upon sliding the battery5horizontally towards the small portion of the keyhole slots14, the connectors11,13are mated together to provide the electrical connection and additional structural support. When the connectors11,13are properly connected, the battery5is substantially concentric with the terminal18. In this position, a pin sleeve12protruding from an outer perimeter of the top surface of the battery5aligns with a pin sleeve15of the terminal18of the motor4. A clevis pin (not shown) can be inserted through the respective pin sleeves12,15to safelock the battery5in place and prevent the battery5from falling out, thus keep the connection intact.

Safety Parachute Deployment Device

FIG. 7illustrates an example embodiment of a mechanism for deploying a ballistic recovery system (BRS)8(also shown inFIG. 8). The BRS8comprises a parachute832in a compartment on top of the cockpit that can be deployed upon loss of lift or another unrecoverable loss of control. Since the BRS8is usually deployed when the aircraft is already stalling, the g-forces on the occupants may go as high as 6-9 g-s. To avoid excessive strain on the passenger upon deployment of the BRS8, the deployment mechanism834for the BRS8is structured in a manner that forces (or at least encourages) the passenger to be positioned in a safe posture upon deployment. For example, the deployment mechanism834is structured such that when activating it, the passenger is likely to be positioned in a safe posture with limbs inside the canopy frame1and a straight spine. Furthermore, the deployment mechanism is structured to in a manner that is highly unlikely to be deployed accidentally.

In an embodiment, the deployment system834for the BRS8includes a pair of push buttons17on an upper portion of hand rails9positioned on an interior of the cockpit in an upper position on windshield frames of either side of the front windshield. The BRS8is deployed upon the passenger activating both push buttons17concurrently (e.g., for at least a threshold period of time). The most instinctive way of activating the push buttons17is to grab both hand rails9with the hands while simultaneously pushing the buttons17with the thumbs. In this position, the passenger is likely to be in a safe posture with straight spine, limbs inside the cockpit, and hands held tight. Furthermore, unintentional activation is highly unlikely.

In an embodiment, BRS deployment automatically cuts off power to all 18 motors4at once. The on-board flight control system810will furthermore notify ground personnel via a radio telemetry channel to indicate deployment of the BRS8, and may furthermore provide other telemetry data from the aircraft100to enable ground personnel to best respond.

Distributed Control System

In an embodiment, the on-board flight control system810of the aircraft100includes a dedicated control channel from the on-board flight control system810to each individual motor4. In the event of a control channel failure, only a single motor is affected, thereby improving flight stability and safety.

In-Flight User Interface

In an embodiment, the aircraft100may include a display screen with an in-flight user interface for enabling a passenger to interact with the aircraft100during flight. In this embodiment, the user interface provides a two-dimensional map illustrating a location of the aircraft100relative to the geography, and may show locations of other aircrafts in the area. The map may furthermore illustrate virtual boundaries outside of which the flight control system will prevent the aircraft100from entering. In an embodiment implementation, an augmented-reality mode overlays information on a real-time view from an on-board camera. For example, the augmented-reality view may overlay air traffic information, airspace boundaries, and a maximum allowed range of the aircraft100. Furthermore, “no-fly” areas corresponding to overly congested areas may be indicated as “no-fly” zones in the augmented-reality view.

Upon reading this disclosure, those of skill in the art will appreciate still additional alternative structural and functional designs for the disclosed embodiments from the principles herein. Thus, while particular embodiments and applications have been illustrated and described, it is to be understood that the disclosed embodiments are not limited to the precise construction and components disclosed herein. Various modifications, changes and variations, which will be apparent to those skilled in the art, may be made in the arrangement, operation and details of the disclosed embodiments herein without departing from the scope.