Abstract: The present disclosure relates to a disk-type brushless direct current (BLDC) motor, which comprises a magnetic rotor and a stator. The magnetic rotor is provided with a rim and a plurality of equally spaced magnetic poles around the rim in circumferential direction. The stator is provided with a stator core having tooth portions and boot portions and a plurality of coil windings wrapped around the tooth portions. The stator is disposed radially in relation to the magnetic rotor such that the magnetic poles are radially polarized to produce radial magnetic flux density, and the magnetic flux density is substantially higher at both edges than middle portion of each magnetic pole in the circumferential direction.

Abstract: A bicycle frame includes a frame body including a top tube, a seat tube, a seat stay, and a mounting unit that is disposed at a junction among the top tube, the seat tube and the seat stay, and that has a base portion, and a position-limiting portion extending from the base portion, a seat post unit including a seat post that extends through the base portion, and a post clamp that is fixedly sleeved onto the seat post, and that is retained in the frame body by the position-limiting portion, a cushion sleeved onto the seat post, and having a tube body that is fittingly disposed between the seat post and the base portion, and a sleeve portion that extends from the tube body, and that is disposed between the post clamp and the base portion.

Abstract: A control device for a bicycle, has a first body adapted to be attached to a bicycle handlebar, at least one control member of at least one bicycle component, and a second body, distinct from the first body, connected to the first body to increase a grip surface of the control device and/or to vary the relative position of the at least one control member with respect to the handlebar of the bicycle, so as to adapt the control device to the size of the cyclist's hand.

Abstract: A wheel mounting member having a damping structure may include a dropout in which an axle insertion groove is formed at one side of a lower portion thereof, wherein a guide slot may be formed in a predetermined direction at a predetermined distance from the axle insertion groove; a bracket in which a protrusion inserted into the guide slot is formed at a lateral surface thereof; and an elastic member that is inserted into the guide slot and elastically supports the protrusion, wherein the elastic member may absorb impact transmitted to the dropout.

Abstract: Telescopic suspension device (10) attached to the hub (422) of a wheel (424) of the type comprising a first tube (12), a second tube (14) sliding relative to the first tube and a main spring (34) arranged inside said tubes, and further comprising a pretension adjustment stopper (18) of the spring (34) installed at the upper end (16) of said first tube. The suspension device comprises a pretension tracking system (39) of the spring, representative of the weight of the user, connected to the stopper (18).

Abstract: A trailing link multi-bar suspension assembly for a cycle having improved stability includes a first arm having a first arm fixed pivot and a first arm shock pivot. A shock link has a shock link fixed pivot and a shock link floating pivot. A shock absorber has a first shock mount and a second shock mount. A wheel carrier has a wheel carrier first pivot and a wheel carrier second pivot spaced apart from one another, and a wheel mount that is adapted to be connected to a wheel. A control link has a control link floating pivot and a control link fixed pivot, the control link floating pivot being pivotably connected to the wheel carrier second pivot, and the control link fixed pivot being pivotably connected to the first arm control pivot.

Abstract: A bicycle operating device comprises a base member and an operating member. The base member includes a hydraulic-unit attachment part to which a hydraulic unit is to be attached, and a first end portion to be mounted to a handlebar. The operating member is movably coupled to the base member. The operating member includes a first wire attachment part to which a first wire end of a control wire is to be attached.

Abstract: A central shaft torque sensing system for an electric bicycle having a center-mounted motor. The system comprises a central shaft, a center-mounted motor and a controller, and also comprises a torque sensor and a strain sleeve. The controller is respectively connected to the torque sensor and the center-mounted motor, and the motor comprises a main housing, a coil stator, a rotor, a motor output gear shaft, a planetary reduction mechanism and a dual-ratchet clutch, one end of the strain sleeve being connected to the dual-ratchet clutch, the other end being sleeved on the central shaft and fixedly connected thereto, the torque sensor being mounted on the sleeve.

Abstract: A saddle-ridden vehicle includes: a pair of frame members which are disposed on one side and on other side in a vehicle width direction so as to extend in a vehicle front-rear direction; an engine which is disposed between and supported by the pair of frame members; an air cleaner which cleans air for fuel combustion; a supercharger which compresses the air cleaned by the air cleaner; an intercooler which cools, using a cooling wind, the air compressed by the supercharger and supplies resulting air to the engine; and an exhaust wind duct which determines a discharge position or a discharge direction of the cooling wind discharged from the intercooler, and the exhaust wind duct is disposed above the engine on the one side in the vehicle width direction and extends to rear of the engine.

Abstract: A rear wheel sprocket arrangement for a bicycle comprises a plurality of sprockets comprising at least seven (7) coaxially arranged sprockets having different numbers of teeth, wherein an entire gear range of the sprocket arrangement is at least three-hundred fifty percent (350%), and wherein an average percentage gear stage step lies within a range of fifteen percent (15%) to thirty percent (30%).

Abstract: A rear derailleur protector for a bicycle comprising a shield to protect the derailleur and mounting means on the shield for mounting the shield on the bicycle, the mounting means being adapted to engage the bicycle and a stand attachable to the derailleur protector to support a bicycle fitted with the derailleur protector in an upright position.

Abstract: A bicycle derailleur is basically provided with a base member, a movable member and an electric actuator. The base member is configured to rotate together with a bicycle sprocket apparatus about a rotational axis of the bicycle sprocket apparatus. The movable member is movable relative to the base member to displace a bicycle chain. The electric actuator is configured to electrically actuate the movable member.

Abstract: A control device with adjustable communication period is configured for an electromechanical gear shifter of a bicycle. The control device comprises a master controller and a trigger sensor. The master controller sends a broadcast signal with a first period when the master controller is in a working mode. The master controller sends the broadcast signal with a period selected from an idle period set when the master controller is in an idle mode. The trigger sensor is in communicable connection with a master controller, and the trigger sensor detects a trigger state to send a trigger signal. The master controller switches to the working mode when the master controller receives the trigger signal. The master controller switches to the idle mode selectively when the master controller does not receive the trigger signal.

Abstract: A lower deck for a watercraft is attached to and supported by an amidships hull, and an actuator slides the lower deck and amidships hull between a stowed position and an extended position on rails that are secured to the underside frame of the upper deck that is supported by abeam hulls. When fully extended, the lower deck remains attached to the watercraft while a portion of the lower deck's aft section remains beneath the upper deck. A hold within the amidships hull can store accessories used with the watercraft, such as live wells, tables, seats, a foldable slide and ladder assembly, and other items which can be accessed and deployed when the lower deck is extended. The holds are covered by panels which may be individual separable panels, a foldable set of connected panels, or laterally expandable panels. The lower deck can have foldable handrails and recessed cup holders.

Abstract: Flow modifiers are positioned at one or more discrete points along the underside of a boat hull to generate secondary wakes that interfere with the primary wake generated by the boat hull and result in a desired modified wake useful for various watersports. The flow modifiers are formed integrally with the boat hull or affixed thereto, and can be selectively extendable and retractable relative thereto.

Abstract: An onboard lift for a pontoon boat has four legs pivotally attached underneath a platform and extending between the outer pontoons. Each leg terminates in a slide foot. The pivot pin for each leg is canted, such as at 13° relative to horizontal. In a stowed position, the legs and slide feet extend forward in the direction of travel and tight to the platform. When used to lift the boat, actuation of the legs pushes the slide feet outward due to the cant of the pivot axis, such that the slide feet are positioned underneath the outer pontoons when the boat is fully raised. The control allows separate powering of the front legs from the rear legs, and further has a display so the user can see the amount of extension of each set of legs.

Abstract: An anchor system for watercraft includes: a hub including a receiving contour; a skirt removably securable to the hub along a receiving contour of the hub, wherein: the skirt at least partially surrounds an inner recess and includes a gap such that such that the skirt is not circumferentially continuous; and the skirt is configurable in an open position and a closed position, wherein when the skirt is in the open position the gap is wider than when the skirt is in the closed position. The inner recess of the skirt has a radius that is larger than a complementary radius of the receiving contour of the hub when the skirt is in the open position. When in the closed position, the radiuses are substantially the same, such that the skirt is secured to the hub when the skirt is in the closed position.

Abstract: The invention relates to floating platform mooring and involves an improved platform mounted tendon tension monitoring system with porch-mounted variable reluctance measurement technology sensors configured. The variable reluctance measurement technology sensors of this system are optimized for porch mounting. The porch-mounted tendon tension monitoring system can also be configured such that the porch-mounted optimized variable reluctance measurement technology sensors are replaceable. Sensors may be replaced to extend the desired useful lifetime of a tendon tension monitoring system or in the event that a sensor happens to malfunction. A plurality of variable reluctance measurement technology sensors can be configured in sensor packs at the corners or at other locations where tendon tension monitoring can be useful for a floating platform.

Abstract: Mooring unit for mooring a ship comprising a base, an arm mounted on the base, and a hook supported by the arm for connecting a mooring line of the ship, wherein the arm is movable between a retracted position and an extended position, and wherein the unit comprises an actuating device for moving the arm from the extended position to the retracted position, wherein the arm is mounted on a first part of the base and wherein the first part of the base is rotatably mounted on a second part of the base that is rotationally fixed, to enable rotation of the first part of the base around a vertical axis perpendicular to the horizon.

Abstract: An LNG tank container transport ship, according to one embodiment of the present invention, which has a load space on the inside thereof, in which LNG tank containers storing liquefied natural gas are loaded, comprises: a crane which is arranged on the upper part of the load space so as to catch a container to be transported; at least one horizontal transport frame which guides the horizontal direction movement of the crane; and at least one vertical transport frame which is connected to the horizontal transport frame so as to guide the movement of the crane in the direction perpendicular to the horizontal transport frame. According to one embodiment of the present invention, there is an effect of providing a dedicated transport ship for LNG tank container transport by having therein a separate load space so as to load LNG tank containers.

Abstract: Described is a device for lifting an object from a deck of a vessel subject to movements in a heave direction. The device comprises a support surface for the object provided at a first height in the heave direction relative to the deck. A lifting crane is configured to take up the object from the support surface at a lifting point thereof at a lifting speed. An actuator system is configured to lower the support surface relative to the deck at the instant in time at which the object is lifted from the surface to a second height in the heave direction at a lowering speed. A method using the device is also described.

Abstract: A floating downwind turbine comprising: a floating foundation; a tower which is rotationally fixed on the floating foundation; an energy conversion unit which is mounted on the tower, comprises a rotor and is rotationally fixedly connected to the tower; and at least one tensioning element which connects the tower or the energy conversion unit to the foundation in the upwind direction, the foundation having three legs, one leg of which is longer than the other two legs, the legs being interconnected in a Y shape and the tower, being arranged on the foundation in the connecting region of the legs, and the longest leg extending in the upwind direction and being connected to the tower or to the energy conversion unit by the tensioning element.

Abstract: Disclosed is a mount for attaching objects, like cameras and bindings to the surfaces of a surfboard. Further disclosed is related methods of fabricating or retrofitting a surfboard with said mount. The more specific details of the disclosed mount and related methods are described in connection with the figures.

Abstract: A spotlight apparatus is provided have an illumination element rotationally and pivotally mounted to a pedestal. A vertical control motor urges the illumination housing up and down. A lateral control motor urges the illumination element left or right. A joystick input provides manual directional control of the vertical motor and lateral motor. A MEMS gyroscope or similar microelectronic controller provides an automated control input that, when activated, provides a continuous control signal for providing vertical and lateral motor control based upon a target set point selected by the user.

Abstract: A survival platform, comprising two flexible outer sheets (4, 5), the outer sheets each having a circumference (2) and being sealed together at their circumferences (2) to define a void (18) therebetween, the survival platform further comprising an inner flexible sheet (6) interposed between the outer sheets (4, 5) and dividing the void (18) into two sub-voids (18a, 18b), and means (8) for inflating the survival platform by introducing a gas into the void to increase a gas pressure therewithin, in which the inner sheet (6) is arranged such that, should one of the outer sheets (4, 5) be breached at a breach, the gas pressure within the void will tend to force the inner sheet (6) through the breach, thereby to block the breach and reduce the level to which gas escapes through the breach.

Abstract: A full face mask and snorkel can include a full face mask and a rigid snorkel attached to the side of the mask. The side location of the ridged snorkel avoids peripheral ducting of air around the full face mask. The full face mask includes a main peripheral full face seal coupled to the mask's rigid support structure. The full face mask includes a separation seal dividing the full face mask into at least an upper chamber. The snorkel is affixed to the side of the full face mask at a location proximate to where the separation seal meets the main seal. A full face mask and snorkel can also include an exhalation valve located within the snorkel and proximate to the mask so as to avoid a volume of respirated air within the snorkel from being reinhaled into the lower chamber of the full face mask.

Abstract: An embodiment of a submersible warming garment comprises a closed fluid loop including a warming conduit disposed in thermal communication with a chamber containing a catalyst and a cooling conduit disposed within a wearable garment. A pump moves the fluid through the warming conduit, where heat is gained, to the cooling conduit, where heat is surrendered to a human wearing the garment, and back to the pump. An actuated valve on a container of fuel and an actuated valve on a container of oxygen are controlled using a controller to provide a combustible mixture into the chamber where the mixture reacts in the presence of a catalytic member to generate heat and combustion by-products. The combustion by-products, including carbon dioxide and water, are one of adsorbed and absorbed by a carbon dioxide scrubber and a reusable water storage medium. A fan moves the by-products into the scrubber and water storage medium.

Abstract: The present invention provides a self-draining oil buoyancy regulating device for underwater robots, wherein the accumulator, lower hatch cover, hatch trunk, upper hatch cover and bladder are connected; the water-proof connector is fixed on the upper hatch cover; the depth-pressure sensor is settled on the lower hatch cover; the upper valve block, hydraulic-operated check valve and lower valve block are connected; the lower valve block is fixed on the lower hatch cover; the pump outlet pressure sensor and the accumulator pressure sensor are on the lower valve block; the directional valve and the upper valve block are connected; the hydraulic pump motor assembly and the relief valve are both connected with the lower valve block; the depth-pressure sensor, pump outlet pressure sensor and accumulator pressure sensor are all connected with the control panel; the control panel is connected with the external power supply and the host computer.

Abstract: A watercraft comprises a motor, an inertial mass, and a fin. The motor oscillates the inertial mass about an axis, producing a torque reaction on and oscillation of the motor. Oscillation of the motor is communicated to the fin, producing thrust.

Abstract: A watercraft propulsion system operably coupled to a watercraft wherein the propulsion system includes a housing assembly having a first housing and a second housing movable with respect to each other so as to provide an operational mode and a standby mode. The first housing includes at least one aperture that is configured to provide access to the interior volume of the first housing. The second housing includes at least one aperture configured to provide access to the interior volume of the second housing. In the operational mode the first housing and second housing are positioned so as to facilitate alignment of the at least one apertures formed therein. In the standby mode the first housing and second housing are positioned so as to provide an offset of the least one apertures. The first housing is movably mounted within the interior volume of the second housing.

Abstract: The device herein comprises a kayak or canoe paddle that allows a user to insert his or her arm and forearm through openings formed within the paddle while he or she grips the paddle. The insertion of the arm and forearm within the paddle allows the user's arm and forearm to provide additional support to the paddle. Additionally, the handle used to grip the paddle is formed perpendicular to the length of the paddle allowing a user to maintain his or her grip on the handle even if the kayak or canoe overturns. Two paddles may be joined together to form a single paddle with either a “V” shape or a linear shape. The “V” shaped paddle enhances the ability of the kayaker to traverse a body of water.

Abstract: A device and a method for starting an internal combustion engine, provided with an exhaust turbine turbocharger, an electric motor generator, a power storage unit, an engine rotation starter device, injectors, and a control device that controls the electric motor generator, the engine rotation starter device, and the injectors, wherein when an engine rotation activation start signal is input and the rotational frequency of the exhaust turbine turbocharger reaches an engine rotation-activation-starting rotational frequency, the control device starts driving the engine rotation starter device, and when the engine rotational frequency reaches a fuel-supply-starting rotational frequency, the control device starts driving the injectors, thus improving the starting performance of the internal combustion engine.

Abstract: A marine muffler capable of handling both marine engine exhaust gas and marine engine cooling water includes a double wall baffle partitioning the muffler interior so as to function as a cooling water conduit. The cooling water conduit includes an inlet disposed external to the main muffler housing and an outlet configured and disposed so as to discharge the engine cooling water into the exhaust duct connected to the muffler outlet. The muffler is thus able to convey the engine cooling water through the muffler housing within a dedicated conduit while maintaining the cooling water separate from the exhaust gas. A muffler that is adapted to handle both the exhaust and cooling water flowing from a marine engine allows for the elimination of engine cooling water piping.

Abstract: A system for transporting hydrogen from where it can be economically made to where it is most needed using airships. Green technologies can be used to generate electricity near to the primary energy sources. This electricity can then be used to produce hydrogen directly from water. Hydrogen can be delivered using an airship in which the hydrogen gas can also be used for generating lift, providing propulsion energy and serving ancillary needs. The ship can be equipped with solar cells that generate electricity that can be used to make hydrogen from water, and can be used to power the ship's propulsion system.

Abstract: A gas density control system for airships is provide. The system embodies a hybrid ballonet and low pressure gas storage tank combination for regulating the density and volume of the airship lift gas, wherein the ballonet is fluidly connected to the storage tank by a transfer hose. The base of the ballonet is also sealed along an exterior surface of the length curvilinear geometric shaped storage tank so that as the storage tank selectively rotates the ballonet either wraps or unwraps around the length, whereby the lift gas transfer to and from the storage tank to the ballonet, respectively. A transfer hose reel is provided to rotate with the storage tank so that as the ballonet wraps about the storage tank the transfer hose winds about the transfer hose reel, and vice versa. Thereby the system precisely adjusts the ballonet's volume, which in turn controls its lifting force.

Abstract: Disclosed herein is a method of repairing damage to a fuselage barrel, having a one-piece construction, of an aircraft. The method includes determining at least a first virtual splice line and a second virtual splice line along the fuselage barrel in a direction parallel to a longitudinal axis of the fuselage barrel. The method also includes detecting damage in a first section of the fuselage barrel between the first virtual splice line and the second virtual splice line. The method further includes cutting through the fuselage barrel along the first virtual splice line and the second virtual splice line to physically separate the first section from a main section of the fuselage barrel. The method also includes removing the first section from the main section of the fuselage barrel, and splicing a new section to the main section of the fuselage barrel in place of the first section.

Abstract: A hat stiffener disclosed herein that includes a web portion having locally optimized slopes. The hat stiffener may include a web portion having a relatively small slope optimized to handle a sheer force. The hat stiffener may further include a web portion having a relatively large slope optimized to handle a pull-off or interface force. The hat stiffener may include a hat cap having variable widths along the length of the hat stiffener. The hat stiffener may further include a transitional web portion to transition from a web portion having a relatively large slope to a web portion having a relatively smaller slope. The concepts disclosed herein allow for the generation of a one-piece hat stiffener, which can be locally optimized to improve structural capability and efficiency for different loading applications.

Abstract: The disclosure herein provides for disbond resistant stringer runouts. Various aspects may be used independently or in combination to mitigate disbonding associated with the stiffener runout under operational loads. Aspects include a stiffener runout having rounded base flange corners. A recessed notch may be incorporated within the base flange to provide a flange termination point that is forward of the web termination point, allowing the web to terminate prior to the base flange. The web may be trimmed from a full height to a reduced height at the web termination point. The base flange may be co-bonded to the underlying composite structure via a scarf joint. Perimeter clamp radius fillers may be used to concentrate a clamping force around the perimeter of the base flange.

Abstract: The invention relates to a structure having a panel, a stringer and a rib. The stringer has a stringer flange that is joined to an inner surface of the panel and a stringer web that extends away from the stringer flange. The rib has a rib web and a rib foot. The rib foot has a rib foot flange that is joined to the stringer web, first and second rib foot base parts that are joined to the inner surface of the panel or to the stringer flange and a rib foot web that is joined to the rib web. The rib foot is formed as a single folded piece such that the rib foot flange is connected to the rib foot web by a first folded corner, the first rib foot base part is connected to the rib foot flange by a second folded corner and the second rib foot base part is connected to the rib foot web by a third folded corner.

Abstract: The present invention is directed to a solar-powered aircraft comprising a fixed wing panel, a motor driven propeller, a plurality of secondary wing panels, and a tail assembly having a first tail panel and a second tail panel. Each secondary wing panel being configured to rotate about a first longitudinal pivot axis extending from a distal end of the fixed wing panel through a central transverse portion of the secondary wing panel. The secondary wing panels may comprise an array of solar panels on its surface. The first tail panel comprises a second array of solar panels located on a surface of the first tail panel, the first tail panel being configured to rotate about a second longitudinal pivot axis through a central transverse portion of the first tail panel.

Abstract: A control system for a flight vehicle includes first and second pivot pins each having a hollow cylindrical shape with an opening therein, first and second deployable wings configured to pivot about the first and second pivot pins between a stowed position and a deployed position with the first and second deployable wings each having first and second wing tip shafts extending between the first and second pivot pins and first and second ailerons at a tip of the deployable wings, first and second lever pins within the opening in the pivot pins with the first and second lever pins each having a first end that extends out from a top of the pivot pin and a second end connected to the wing tip shaft and with the first and second lever pins configured to rotate the wing tip shafts to control the ailerons.

Abstract: An unmanned moving vehicle piloting method and an unmanned moving vehicle watching device enabling it to pilot an unmanned moving vehicle, while keeping in visual contact with the vehicle from the vicinity of the vehicle from a third person viewpoint. In the vicinity of an unmanned moving vehicle, a watching aircraft is positioned, which is an unmanned aerial vehicle and includes a single or a plurality of rotors and image capturing means capable of capturing an image of surroundings of the watching aircraft and is able to stand still at one point in the air and piloting the unmanned moving vehicle, while viewing a third person viewpoint image captured by the watching aircraft. Moreover, the watching aircraft includes accompanying flight means for causing the watching aircraft to fly automatically, following movement of an unmanned moving vehicle. This enables the manipulator to concentrate solely on piloting the unmanned moving vehicle.

Abstract: According to a first aspect of the invention, there is provided a method for operating a multicopter experiencing a failure during flight, the multicopter comprising a body, and at least four effectors attached to the body, each operable to produce both a torque and a thrust force which can cause the multicopter to fly when not experiencing said failure.

Abstract: Example active flow control systems and methods for aircraft are described herein. An example method includes supplying pressurized air to a plurality of nozzles. The nozzles arranged in an array across a control surface of an aircraft, and the nozzles are oriented to eject the pressurized air in a substantially streamwise direction. The method further includes activating the nozzles to eject the pressurized air in sequence to create a wave of air moving in a spanwise direction across the control surface.

Abstract: Aircraft landing gear comprising a locking assembly including a pair of spaced-apart bearing pads and a lock member. The lock member is moveable between a locked position in which it engages the bearing pads to prevent pivotal movement of a steerable axle, and an unlocked position in which the member is disengaged from the bearing pads such that movement of the axle can occur. The lock member has a guide surface on either side for guiding the member and bearing pads into alignment during movement of the member from the unlocked to the locked position. The guide surface comprises a first inclined portion for moving the member towards alignment with the bearing pads and a second inclined portion, spaced apart from the first portion, for moving the member into alignment with the bearing pads such that the member and bearing pads are aligned in a movement comprising two stages.

Abstract: A monitoring system is provided to ensure continued efficient reliable operation of an aircraft drive wheel drive system, preferably an aircraft drive wheel drive system driven by actuating drive system-actuated drive means, designed to drive an aircraft autonomously during ground operations. The monitoring system includes an array of sensor elements capable of obtaining desired information relating to selected drive system operating parameters and performance indicators during aircraft ground operations. The sensor elements are designed to be functionally located externally of drive system components to obtain information during aircraft ground movement under a range of operating conditions. The operating parameters and/or performance indicators to be monitored preferably include at least drive wheel speed and direction, drive means speed, drive means temperature, and drive means clutch engagement.

Abstract: Apparatus for controlling velocity of aircraft during landing roll-out and/or taxiing, the apparatus comprising: a generator for absorbing kinetic energy from a landing gear of the aircraft to generate electrical energy; and a component of the aircraft for receiving and consuming electrical energy from the generator, the generator and the component being electrically connected to one another without an intervening electrical energy storage device.

Abstract: A control system for resonant inertial actuators estimates operating parameters of the resonant inertial actuators based on voltage and current feedback and dynamically limits selected parameters to maintain the safe, efficient, and cost effective operation of the resonant inertial actuators. Resistance within the electrical drives for the resonant inertial actuators is estimated from the voltage and current feedback and in conjunction with the modeling of the resonant inertial actuators other operating parameters are calculated or otherwise estimated. Having regard for the responsiveness of the resonant inertial actuators to changes in command signals, the command signals are adjusted to dynamically limit the estimated parameters.

Abstract: An improved vibration control actuation system for a rotary-wing aircraft having a plurality of rotor blades mounted to a rotor hub and driven about a central axis of rotation at an operational speed and in a rotational direction relative to a non-rotating body of the aircraft comprising a vibration control frame adapted to be mounted to the hub and to rotate relative to the hub about the central axis in a rotational direction opposite to the rotational direction of the hub, a frame motor configured to rotate the frame about the central axis, the frame supporting first and second motors configured to rotate first and second masses about first and second axes not concentric with the central axis, and a controller for receiving input signals and outputting command signals to the first and second motors.

Abstract: A rotor hub assembly for a rotorcraft includes a yoke forming a bearing bore. The yoke has a teetering axis extending through the bearing bore. The rotor hub assembly includes a flapping bearing disposed in the bearing bore. The flapping bearing is operable to regulate teetering of the yoke about the teetering axis. The rotor hub assembly includes an axial spring abutting the flapping, thereby reducing movement of the flapping bearing along the teetering axis.