Abstract: A vehicle comprising a framework in form of beam, wheel, drive and braking system, while the vehicle is partially loaded with the weigh of user and the user stands on roller skates and holds the vehicle on the beam so that the wheel is behind the user and contacts with its tire the road surface; and when the user activates the drive, the wheel starts rotating and, as a result of friction between the wheel's tire and the road surface, there arises a force making the vehicle with user move. Additionally, another technique for operation of the same vehicle is being offered, at which the vehicle on the move is positioned in the front of user.

Abstract: A system for lubricating a pivot interface defined between adjacent components of a work vehicle may include a shaft and a shaft housing configured to receive an axial portion of the shaft such that the shaft housing is configured to rotate relative to the shaft. The system may also include an end cap installed relative to an end of the shaft housing and a sealing device configured to seal a radial gap defined between the shaft housing and the shaft at a seal location when a fluid pressure within the housing is below the seal's cracking pressure. Additionally, when the fluid pressure within the housing exceeds the cracking pressure, the sealing device may be configured to transition to an unsealed state to allow lubricant contained within the housing to flow axially between the sealing device and the shaft and be subsequently purged from the housing.

Abstract: A tracked vehicle has a pivotable suspension. The vehicle includes a vehicle frame, a motor configured to produce power for the vehicle, and left and right track assemblies that are each connected to the frame. The assemblies each have a drive wheel configured to be driven by the motor, an endless track driven by the drive wheel, wherein the endless track has an outer side and an inner side, a bogie positioned on the inner side of the endless track, a support wheel attached to the bogie and configured to roll on the endless track, a strut connected to the frame and to the bogie, and a shock absorber connected to the frame and to the strut. The strut and the shock absorber are pivotable relative to the frame. The vehicle may have low ground pressure, consistent traction, and may be modularly configured with a floatable hull for aquatic travel.

Abstract: A track system for traction of a vehicle (e.g., a snowmobile, an all-terrain vehicle (ATV) etc.). The track system comprises a track and a track-engaging assembly for driving and guiding the track around the track-engaging assembly. The track system may have various features to enhance its traction, floatation, and/or other aspects of its performance, including, for example, a lightweight design, enhanced tractive effects, an enhanced heat management capability, an enhanced resistance to lateral skidding (e.g., on a side hill), an adaptive capability to adapt itself to different conditions (e.g., ground conditions, such as different types of snow, soil, etc.; and/or other conditions), an adjustability of a contact area of its track with the ground, and/or other features.

Abstract: A sprocket (10) is capable of engaging with engaging portions (22) on an elastic endless belt (21). On a tooth face (F) of a tooth (12) of the sprocket (10), a portion of a tooth base on at least one side of a center line (O1) of the tooth (12) is a tooth base surface (12b), and the tooth base surface (12b) is inclined relative to the center line (O1) of the tooth (12) at an angle (A1) in a range of 0° or greater to 7.5° or less so as to approach the center line (O1) of the tooth (12) towards a tooth tip surface (12d).

Abstract: An example instrument panel includes a plurality of modules and first and second section. Each section includes a module-receiving area. The plurality of modules are interchangeable. The module-receiving areas can each receive at least one of the plurality of modules. An alternate instrument panel and a method of assembling also include interchangeable modules.

Abstract: A manufacturing plant (1), for workpieces (29), includes a plurality of manufacturing stations (2 to 5) and a conveying system (9) for conveying the workpieces within the manufacturing plant (1) and between the manufacturing stations (2 to 5). Mobile automatic conveying devices (13, 14, 15) travel on a conveying path network (11) of a plurality of interlinked conveying paths (10) intersecting each other. The conveying paths (10) are connected to a plurality of manufacturing stations (2 to 5) arranged in a station matrix (8).

Abstract: The present invention relates to an assembly for storing bicycles, the assembly including: at least one fixed rail; and a support frame on which at least one bicycle can be loaded in an elevated position above the ground, wherein the support frame is moveable on the rail between a forward advance position for loaded and unloading the bicycle from the support frame, and a rearward retracted position for storing the bicycle. When the support frame is in the forward advanced position, a bicycle loaded onto the support frame can be locked to the support frame using a conventional bicycle lock.

Abstract: A bicycle seat assembly includes a bicycle seat including a front portion and a rear portion and rear portion and mounting platform attachable to a bicycle seat post or seat post adaptor of a bicycle. One portion of the bicycle seat releasably attaches to a portion of the mounting platform and another portion of the bicycle seat releasably attaches to another portion of the mounting platform.

Abstract: A straddle vehicle which turns in a bank state in which a vehicle body is rotated around an axis extending in a vehicle length direction, includes a head lamp unit which is disposed at a front portion of the straddle vehicle and emits a light beam with which a forward region of the vehicle body is irradiated; a cornering lamp unit which is disposed at the front portion of the straddle vehicle, provided separately from the head lamp unit, and turned on in the bank state; and a duct member included in an engine air-intake system, wherein the cornering lamp unit is disposed below the head lamp unit and below an air-intake inlet of the duct member.

Abstract: A lighting device structure includes lighting sources configured to provide lighting illumination, a reflector configured to reflect lighting illumination from the lighting sources as the LED elements, an inner lens mounted to the reflector. The lighting sources, the reflector, the inner lens are housed within a housing, and an outer lens assembled to the housing. The inner lens is mounted to a front end of the reflector and comprises an overlapping portion positions between an outline wall of the reflector and the inner lens. The overlapping portion of the inner lens induces lighting illumination and illuminates the inner lens. The inner lens is mounted to the front end portion of the reflector that does not obstruct to the certain lighting illumination, and comprises a pair of arms which extended closely to the lighting source, such that the inner lens can induce and illuminate itself as the auxiliary light.

Abstract: A bicycle including a handlebar attached to a frame at substantially a midpoint, a first set of light sources disposed to project light in a first forward direction, said first set of light sources including a fixed light source and a motor-controlled light source, disposed to project light in a second forward direction said second set of light sources including a fixed light source and a motor-controlled light source, a controller, said controller disposed on the handlebar, said controller coupled to the first set of light sources and the second set of light sources, a rotation sensor operable to sense movement of the handlebar relative to the frame, said rotation sensor coupled to the controller, wherein the motor-controlled light sources move in response to the position of the rotation sensor.

Abstract: An attachment system for securing an accessory to a vehicle is disclosed. The attachment system generally comprises at least a locking mechanism mountable to, or integral with, the accessory, and a base mounted to, or integral with, the vehicle. The locking mechanism generally comprises an actuator configured to actuate or displace at least a pair of locking elements between an inoperative (or unlocked) position and an operative (or locked) position. The base generally comprises at least one opening configured to at least partially receive the locking mechanism. The attachment system generally allows the installation and removal of the accessory by actuating the actuator of the at least one locking mechanism.

Abstract: System for assisting in driving a bicycle by sending a haptic feedback to a cyclist having means for detecting the current value of a target quantity (q, v); and a memory module configured for supplying an optimal value of the target quantity (qmax; vmax) corresponding to the current spatial position (x) of the bicycle along the predetermined path or corresponding to the current instant (t). A comparator module is configured for determining a quantity representative of the error (eq; ev) between said current value of the target quantity (q, v) and said optimal value of the target quantity (qmax; vmax) supplied by the memory module. An actuator is applicable to a portion of the bicycle (100), suitable for generating vibrations. A control module is configured for determining a vibration frequency (f) of the actuator based on the error (eq; ev), wherein the said vibration implements the haptic feedback to the cyclist.

Abstract: In the electric component support structure for the saddle ride vehicle including a body frame F that supports a water-cooled engine, and a radiator that is supported on the body frame through collars, a gyro sensor is fixed to electric component support pieces provided on the radiator.

Abstract: A bicycle frame system comprises a connection module that rotatably connects a front frame section to a rear frame section. The connection module comprises a hinge section and a clamp section. The hinge section is below the clamp section when the bicycle frame system is in a ridable orientation. The connection module hinge section has a horizontal axis of rotation configured for rotating a front bicycle frame section approximately 180 degrees downwards and rearwards relative to a rear bicycle same frame section to convert the bicycle frame system from a ridable configuration to a folded configuration. The connection module clamp section comprises a front clamp block, a rear clamp block and a fastening device. The fastening device is configured to secure the front clamp block to the rear clamp block when the bicycle frame system is in a ridable configuration.

Abstract: A bicycle handlebar system that ensures comfort, safety, increasing center of gravity control. An ergonomic bicycle handlebar system including a hood having: a hood sweep angle from a top bar hood to a first portion of a drop, a drop angle from the first portion of a drop to the second portion of a drop, a thumb index; and a palm flat segment. The coefficient ergonomic bicycle handlebar may be made of nano tube zlyte resin with graphene impregnated carbon fibers.

Abstract: A manual control device having a support body extending longitudinally from a first part configured for fixing to bicycle handlebars to a second part generally opposite the first part; there being generally defined on the support body a rear surface on the first part for fixing to the handlebars, a front surface on the second part, an upper surface, a bottom surface, a proximal side surface and a distal side surface. The support body has a protuberance and a seat for a hydraulic assembly comprising a hydraulic cylinder defining a cylinder axis. An angle (ALFA), defined, in a section through a substantially middle longitudinal plane of the manual control device, between (i) a tangent to the upper surface of the support body in a region not involved in the protuberance and (ii) the axis (C) of the hydraulic cylinder of the hydraulic assembly is between 70° and 118°.

Abstract: Provided is an inverted pendulum type vehicle including a drive wheel and a boarding part on which a rider rides in a standing position, the inverted pendulum type vehicle including: a detection unit configured to detect a drive torque of the drive wheel to maintain an inverted state; and an output unit configured to generate torque information about an ankle torque based on the drive torque detected by the detection unit and output the generated torque information, the ankle torque being applied to the boarding part by the rider.

Abstract: Propulsion unit for an electric pedal assisted cycle (EPAC) comprising an electric machine having a stator and a rotor, rotatable about a motor axis, said rotor (16) being operatively connected to a crank pin, defining a crank axis, mechanically connected to the pedals, wherein the propulsion unit comprises at least an electronic unit for operating and controlling the functioning of the electric machine, wherein the propulsion unit comprises at least a pair of housings defining a containment space which houses the electric machine and at least partially the crank pin, wherein the propulsion unit comprises transmission means of the motion from the rotor to the crank pin, wherein the electronic unit is contained and supported inside said containment space by an intermediate support element.

Abstract: A directional transmission mechanism, a directional sprocket apparatus using the directional transmission mechanism, and a pedal device using the directional sprocket apparatus are disclosed. The directional transmission mechanism includes a driving shaft, an output shaft, a co-rotating wheel, a reverse-rotating wheel, and a switching mechanism. The co-rotating wheel set drives the output shaft to rotate in a direction that is the same as that of the driving shaft. The reverse-rotating wheel set drives the output shaft to rotate in a direction opposite to that of the driving shaft. The switching mechanism switches the driving shaft to drive the co-rotating wheel set or drive the reverse-rotating wheel set to rotate, so as to enable the output shaft to rotate directionally. The co-rotating wheel set is connected with the driving shaft and the output shaft, and the reverse-rotating wheel set is connected with the driving shaft and the output shaft.

Abstract: A wireless control system for a bicycle may include a base part attachable to a bicycle and a movable part. The control system may also include an electric motor disposed on the electromechanical component and a control unit disposed on the electromechanical component for operating the electric motor to operate the electromechanical component, the control unit including a wireless receiver. The control system includes a wake sensor connected to the control unit, the wake sensor configured to cause the control unit and the wireless receiver to become operational in response to detected vibrations of the bicycle.

Abstract: A snowmobile has a frame, a front and a rear suspension assembly connected thereto, at least one ski, an endless drive track, and a motor. The frame includes a longitudinally extending tunnel, the rear suspension assembly being connected thereto. The tunnel includes a top wall extending generally horizontally and comprising a left edge and a right edge. A planar left bevel wall extends downwardly and leftwardly from the left edge. A left side wall extends downwardly from the left bevel wall. A planar right bevel wall extends downwardly and rightwardly from the right edge. A right side wall extends downwardly from the right bevel wall. An upper rear support includes a left leg and a right leg, each having a lower end connected to the corresponding one of the left bevel wall and the right bevel wall and extending forwardly, upwardly and laterally inwardly therefrom to an upper end.

Abstract: A fairlead includes a chain guide support structure and a clump weight engagement member. A clump weight assembly includes a clump weight body, a clump weight coupled to the clump weight body, and a spring housing. The spring housing includes an upper housing wall and at least one spring operatively coupled between the upper housing wall and the clump weight. The clump weight body may be selectively engageable and disengageable with the fairlead to form a fairlead and clump weight assembly. A method of installing and using the clump weight includes engaging the spring housing with the clump weight engagement member, and latching the clump weight body to the clump weight engagement member.

Abstract: A fairing intended to fair an elongate object intended to be at least partially immersed, the fairing comprises a plurality of fairing portions, each fairing portion comprising a plurality of fairing elements, the fairing elements comprising a canal intended to accept the elongate object and being profiled in such a way as to reduce the hydrodynamic drag of the at least partially immersed elongate object, the fairing elements being intended to be pivot-mounted on the elongate element around the longitudinal axis of the canal, the fairing elements being joined together along the axis of the canal and articulated to one another, the portions of fairing rotating freely about the canal relative to one another.

Abstract: Methods for controlling tension in mooring lines of a floating offshore structure having a buoyancy structure including one or more water tanks and the buoyancy structure providing excess buoyancy are provided. The methods comprise varying the mass and/or the center of gravity of the floating offshore structure by varying the quantity of water in one or more of the water tanks. Also, floating offshore structures are disclosed, the structures comprising a buoyancy structure having one or more floater tanks providing excess buoyancy, and a plurality of tensioned mooring lines, and further comprising a control system for increasing and decreasing a quantity of water in one or more of the floater tanks. Also, possible uses of floating offshore structures are provided wherein under standard operating conditions, the floater tanks are at least partially filled with water.

Abstract: A vessel including a boom construction, especially a gangway construction, for transferring persons and/or cargo from said vessel to an offshore object or vice versa. The boom construction includes an elongated mast structure extending in a direction substantially upwards from a deck of said vessel. Said mast structure is pivotally mounted with respect to a hull of the vessel in a manner such as to be pivotable with respect to said hull about a single pivot axis only. The boom construction further includes a boom, especially a gangway, which is connected to the mast structure and which extends from the mast structure in a substantially sideward direction. Furthermore, the boom construction includes at least one actuator for pivoting the mast structure such as to compensate for at least a part of a roll movement of the hull of the vessel.

Abstract: A swim platform for attachment to a boat includes a rearwardly tapered inflatable body including a top surface capable of supporting a standing person, an outer perimeter including a forward wall, an aft wall, and a port sidewall and a starboard sidewall extending between the forward wall and aft wall. The forward wall is positionable adjacent the transom. The forward wall is longer than the aft wall and is configured not to extend laterally beyond the starboard and port sides at the transom. The swim platform may be left in the water while the boat is moving and is designed not to interfere with the boat's wake.

Abstract: A remote operated vehicle for selectively harvesting a target species in an aquatic environment is disclosed. The vehicle may include a chassis defining a central channel and being configured to hold a plurality of attachments mounted to the chassis. The plurality of attachments may include at least one thruster configured to propel the vehicle in the aquatic environment, and at least one electronics containment unit configured to store one or more electronic devices for controlling an operation of the vehicle. The vehicle may also include a containment unit connected to the chassis and configured to store the target species during harvesting, and at least one stunning device configured to stun the target species. The vehicle may further include at least one suction device positioned at a rear portion of the chassis and being configured to generate flow in a direction extending through the channel to cause the target species to flow into the containment unit.

Abstract: A system for underwater remotely operated vehicles (ROVs) and wirelessly controlled subsystems is provided. The system comprises an ROV and a subsystem mounted to the ROV. The ROV includes a microcontroller, a main battery, and a transmitter-receiver. The subsystem includes a controller and a transmitter-receiver. The ROV is configured to communicate wirelessly with the subsystem via signals transmitted between the ROV transmitter-receiver and the subsystem transmitter-receiver. The system can further comprise a control center having a transmitter-receiver configured to communicate wirelessly with the ROV transmitter-receiver and the subsystem transmitter-receiver. The system can further comprise at least one relay module configured to relay signals between the transmitter-receivers of the system. The ROV of the system can also be configured to wirelessly transfer power from the main battery to the power source of the subsystem, such as by resonance coupling.

Abstract: This disclosure is related with propeller noise and cavitation abatement in applications like propulsion, ventilation, pumping or turbine systems on fluids by novel techniques that allows stronger propellers with improved laminar flow by means of a propeller which consists on a rotating cylindrical block or a truncated substantially conical block with one or more tunnels around it rotational axis, said block also may have flow-guiding structures at both ends that help to keep the fluid's laminar flow when it is mixing fluids with its environment, having the rotating block tunnels with either substantially circular shaped cross-section or variable shape cross-section from substantially circular to irregular oval measured in perpendicular plane to the rotational axis whereby it smoothly accelerates fluid or gas by means of either centrifugal or axial movement, also including Dynamic Balance or Imbalance or Torque Modulation Means that modulate specific vibrations which generates sound waves.

Abstract: A wing for the propulsion of a craft includes an external envelope and at least one profile structure surrounded by the external envelope. The profile structure has an articulated internal structure and an assembly of controllers to control a deformation of the external envelope. Each controller is rotatably mounted with respect to the internal structure. Each controller is also rotatably mounted with respect to the external envelope through at least one rotating link, and includes at least one curved surface configured to orient a curvature of the external envelope locally between a controller and an adjacent control controller.

Abstract: A system for providing marine propulsion is provided including an input shaft driven by a prime mover, a pinion gear coupled to the input shaft, a plurality of planet gears coupled to the pinion gear, a planet carrier having the plurality of planet gears rotationally mounted thereto, and a ring gear surrounding the planet gears and coupled thereto. The planet carrier and ring gear are coupled to internal and external output shafts that are coaxially aligned, which are coupled to aft and forward propulsor elements. The ring gear and planet carrier rotate in opposite directions to provide contra-rotating forward and aft propulsor elements. The ring gear and planet gear are each coupled to rotation altering devices that, when at least one is activated, the rotation of both the planet carrier and ring gear will be altered, thereby altering the rotation of the propulsor elements.

Abstract: A swimming propulsion device. The swimming propulsion device includes a fuselage at least one propulsor pivotally connected to the fuselage, and in some embodiments, at least one stabilizer affixed to the fuselage. The device also includes a swimmer connection mechanism removably attached to the fuselage by a locking mechanism whereby the swimmer connection mechanism connects a swimmer to the device, and a control mechanism installed within the propulsor. A method for efficient swimming is also disclosed.

Abstract: An outboard motor and methods of use thereof in general, includes a powerhead removeably affixed to the transom of a boat, and a gear case rotationally connected to a propeller shaft, the outboard motor including a telescopic drive shaft, the telescopic drive shaft having a first drive shaft section rotationally connected to the motor and a second drive shaft section rotationally connected to the gear case, and a telescopic drive shaft housing, the telescopic drive shaft housing configured to support the telescopic drive shaft internally therethrough, whereby the telescopic drive shaft and the telescopic drive shaft housing are configured to provide depth adjustment for the gear case and the propeller shaft, and thus enable the propeller to be raised and lowered during propulsion to improve propulsion efficiency.

Abstract: The present invention relates to a drive system for outboard motors. The drive system comprises a combustion engine having a crankshaft adapted to rotate about a substantially vertical axis. The combustion engine further comprises a camshaft extending parallel to the vertical crankshaft. A high pressure fuel pump is provided for supplying high pressure fuels to the combustion cylinders. The high pressure fuel pump is directly driven by the camshaft.

Abstract: A ship comprises an engine; a first self-heat exchanger which heat-exchanges boil-off gas discharged from a storage tank; a multi-stage compressor which compresses, in multi-stages, the boil-off gas that passed through the first self-heat exchanger after being discharged from the storage tank; a first decompressing device which expands one portion of the boil-off gas compressed by the multi-stage compressor; a second self-heat exchanger which heat-exchanges the other portion of the boil-off gas compressed by the multi-stage compressor, with the boil-off gas expanded by the first decompressing device; and a second decompressing device which expands the boil-off gas pre-cooled by the second self-heat exchanger and cooled by the first self-heat exchanger, wherein the first self-heat exchanger uses the boil-off gas discharged from the storage tank as a refrigerant for cooling the boil-off gas that passed through the second self-heat exchanger after being compressed by the multi-stage compressor.

Abstract: Example transmissions for rotating coaxial drive shafts in opposite directions are described herein. An example apparatus includes a first face gear coupled to a first drive shaft, a first elliptically interfacing gear coupled to a second drive shaft and facing toward the first face gear, the second drive shaft disposed within and coaxially aligned with the first drive shaft, and a wobble plate disposed between the first face gear and the first elliptically interfacing gear. The wobble plate has a second face gear on a first side of the wobble plate engaged with the first face gear and a second elliptically interfacing gear on a second side of the wobble plate engaged with the first elliptically interfacing gear. The wobble plate is to rotate the first face gear and the first elliptically interfacing gear in opposite directions.

Abstract: A boat having an electric motor coupled with an electrical store is disclosed. The electrical store includes a storage element, and positive and negative poles in current-conducting connection with the storage element. An isolating circuit element is operatively connected to a user activatable emergency stop switch. The isolating circuit element is configured to, upon activation of the emergency stop switch, isolate the current-conducting connection between the storage element and at least one of the poles.

Abstract: An access device enables controlled or secure communication between different areas of an enclosure, and in the example illustrated in the present application of an aircraft, while providing reduced size. The access device includes a folding door which, when in folded position, allows at least one of said openings to be closed and, when in deployed position, forms a security vestibule with at least one movable shutter allowing said opening created by the deployment of said folding door to be closed. By superimposing the main components of the security vestibule that said components allow to close, the device frees up the adjoining cabin space when the security vestibule is not in use.

Abstract: A component, including a part, comprising a honeycomb-like structure formed from at least a seamless resin-infused fiber composite material. The honeycomb-like structure includes a first plurality of honeycomb-like cells, and a second plurality of honeycomb-like cells, different than the first plurality of honeycomb-like cells.

Abstract: A high stiffness hub assembly for a rotor system operable to rotate with a mast of a rotorcraft. The hub assembly includes a yoke and a constant velocity joint assembly. The yoke has a plurality of blade arms each configured to hold a rotor blade. The constant velocity joint assembly provides a torque path from the mast to the yoke that includes a trunnion assembly, a plurality of drive links and a plurality of pillow blocks. The trunnion assembly is coupled to the mast and has a plurality of outwardly extending trunnions. Each drive link has a leading bearing coupled to one of the trunnions and a trailing bearing coupled to one of the pillow blocks. Each pillow block is independently mounted between an upper surface of the yoke and a hub plate.

Abstract: A system and method for controlling an aircraft propeller are provided. In anticipation of a condition in which a parameter related to an angle of a plurality of blades of the propeller reaches a value beyond a predetermined threshold, a first control signal is output comprising instructions to actuate a feather valve operatively coupled to an actuator configured to adjust the angle in response to hydraulic pressure, thereby causing the feather valve to provide the hydraulic pressure to the actuator and the angle to be adjusted for bringing the parameter towards the threshold. When the parameter reaches the predetermined threshold, a second control signal is output comprising instructions to hold the feather valve at a position in which the hydraulic pressure is withheld from the actuator, thereby causing the angle to remain unchanged.

Abstract: A device and system for monitoring a load or applied force includes a body having first and second ends, a plate, a force-providing member connected to the plate, a first biasing member, and a first sensor. In embodiments the first biasing member is disposed between a portion of the body at or about the first end and a portion of the plate, and is configured to substantially retain the plate in an initial position during normal operation of the device; the first sensor is configured to sense a displacement (e.g., displacement position) with respect to the plate; and the body includes a portion configured to connect to or apply a force to another component. A controller may selectively instruct and/or operate a component, such as a motor, in response to an output generated or provided by the sensor. If an excessive force is sensed, the device may mitigate resulting damage.

Abstract: An aircraft including a wing (1) and a wing tip device (6). The wing tip device (6) is moveable between a flight configuration for use during flight and a ground configuration for use during ground-based operations. In the ground configuration the wing tip device is folded inwardly from the flight configuration such that the span of the aircraft is reduced. The wing tip device (6) is connected to the wing along a hinge axis (14) by spar beams (10 and 12) of the wing tip device, one of the beams being mounted for pivoting about a fixed axis and the other beam being mounted on a spherical bearing (15) to provide greater freedom of movement. Various actuator arrangements may be provided to pivot the wing tip device.

Abstract: A rotary wing aircraft including a vehicle vibration control system.

Abstract: A detachable power transfer device for a rotary-wing aircraft includes a docking station integrated into the rotary-wing aircraft. A power pod of the detachable power transfer device is constructed and arranged to detachably connect to the docking station for transferring power to the rotary-wing aircraft.

Abstract: Aerial vehicles may be equipped with propellers having pivotable blades that are configured to rotate or fold when the propellers are not rotating under power. A pivotable blade may rotate about an axis of a propeller with respect to a hub in the presence of wind flow until the pivotable blade is coaligned with a fixed blade, in a direction opposite to the wind flow. A pivotable blade may also fold over a hub of a propeller in the presence of wind flow, with the pivotable blade and a fixed blade being oriented in directions opposite to the wind flow. A center of mass of the pivotable blade may be caused to be on the same side of an axis as a center of mass of a fixed blade, even where the axis is not normal to the wind flow, thereby reducing an amount of drag generated by the propeller.

Abstract: A method of assisting in rotor speed control in a rotorcraft can include measuring a rotor speed with a sensor; detecting a droop in the rotor speed beyond a lower droop limit; and commanding a decrease in collective in response to the rotor speed drooping beyond the lower droop limit. A system of assisting in rotor speed control in a rotorcraft, the system can include: a computer having a control law, the control law operable to generate a decrease collective command to an actuator in response to a rotor speed decreasing below a lower droop limit; wherein the lower droop limit is below a normal lower rotor speed range.

Abstract: An aircraft includes a fuselage, a forward wing assembly, and aft wing assembly, and a propulsion system. The propulsion system includes a port forward propulsor and a starboard forward propulsor, each of which rotatable between a forward thrust position and a vertical thrust position and together defining a maximum forward thrust capability. The propulsion system also includes a port aft propulsor and a starboard aft propulsor, each of which also rotatable between a forward thrust position and a vertical thrust position, and together defining a maximum aft thrust capability. The maximum forward thrust capability is different than the maximum aft thrust capability to achieve certain efficiencies.