A vibration control assembly includes a housing having an interior region and an inner mass including a cage disposed within the interior region of the housing and being rotatable within the housing about a first axis and a gyroscope wheel disposed within the cage and rotatable about a second axis other than the first axis. At least one driving source includes a stator and is operable to interact with a magnetic field of the inner mass to drive rotation of the inner mass about at least one of the first axis and the second axis, wherein the at least one driving source is mounted within the interior region of the housing.

Mechanical vibrations are generated on a frame of an aerial vehicle as a response to operation of the aerial vehicle, such as rotation of motors and/or propellers. Likewise, environmental conditions, such as wind, humidity, etc., may also cause vibrations on the frame of aerial vehicles. These vibrations may be destructive to the aerial vehicle, impact stability of the aerial vehicle, and/or result in audible sounds. Disclosed are systems and methods for measuring and/or predicting the vibrations on the frame of the aerial vehicle, generating anti-vibrations, and outputting those anti-vibrations such that the anti-vibrations modify vibrations on the frame of the aerial vehicle.

In some examples, an aircraft comprises an airframe, a rotor system coupled to the airframe, and a vibration attenuation system. The rotor system is operable to exert a vibratory force on the airframe. The vibration attenuation system comprises two or more batteries and elastic devices. The two or more batteries are operable to supply power to the rotor system. The elastic devices coupled to the two or more batteries and the airframe. The elastic devices are configured to attenuate the vibratory force based on facilitating oscillation of the two or more batteries. In other examples, a method comprises coupling elastic devices to two or more batteries and an airframe of an aircraft. The elastic devices receiving a vibratory force via the airframe and attenuate the vibratory force based on facilitating oscillation of the two or more batteries.

A strut assembly for a vibration isolation device is disclosed, comprising a piston spindle; a first elastomeric member and a second elastomeric member bonded to the piston spindle and in contact with an upper housing and a lower housing, respectively; a first strut support and a second strut support attached to or integral with the upper housing and the lower housing, respectively; a first strut spindle and the second strut support configured to be placed in the first strut support and the second strut support, respectively; and one or more removable struts configured to be engaged to the first strut spindle and to the second strut spindle, wherein at least one of the first or second strut spindles is removable such that the one or more struts can be replaced without breaking a bonding of the first elastomeric member, the second elastomeric member, or both.

An aircraft includes a wing positioned below a vertical rotor, the wing extending in a transverse direction to a wingtip having an outboard face, and a turbulence feature located on the wingtip and oriented to induce turbulence in the rotor downwash flowing across the outboard face in a direction from a top surface of the wing to a bottom surface of the wing.

In an embodiment, a rotorcraft includes an airframe; a main rotor transmission; one or more brackets mounting the main rotor transmission to the airframe, longitudinal axes of the one or more brackets being substantially parallel with a longitudinal axis of the rotorcraft; and one or more restraints mounting the main rotor transmission to the airframe, the one or more restraints being mounted at an angle non-orthogonal to the longitudinal axis of the rotorcraft and a lateral axis of the rotorcraft.

A strut assembly for a vibration isolation device is disclosed, comprising a piston spindle; a first elastomeric member and a second elastomeric member bonded to the piston spindle and in contact with an upper housing and a lower housing, respectively; a first strut support and a second strut support attached to or integral with the upper housing and the lower housing, respectively; a first strut spindle and the second strut support configured to be placed in the first strut support and the second strut support, respectively; and one or more removable struts configured to be engaged to the first strut spindle and to the second strut spindle, wherein at least one of the first or second strut spindles is removable such that the one or more struts can be replaced without breaking a bonding of the first elastomeric member, the second elastomeric member, or both.

A piston for use in a liquid inertia vibration elimination (“LIVE”) system. The piston includes a port that extends from a first end of the piston to an opposite second end of the piston, wherein a length of the port is longer than a length between the first and second ends of the piston.

A linear vibration damper and/or absorber includes a centre shaft (12) having bearing regions (18) and friction contact regions (20), and a housing (2) including finger assemblies (22) which are mounted with a small radial clearance for accurate location on the bearing regions (18) for axial displacement with respect to the centre shaft (12) along a central axis (X), the finger assemblies (22) each including resilient fingers (38) which extend axially from respective body sections (26) and have contact faces (40) which resiliently engage, i.e. are pressed by the resilience of the fingers (40) into contact with, friction surfaces (20) of the contact regions of the centre shaft (12), whereby relative linear displacement between the centre shaft (12) and the housing (2) is opposed by frictional contact between the friction surfaces (20) and the contact faces (40).

An exemplary tiltrotor aircraft includes a fuselage carrying a wing, a pylon assembly coupled to the wing such that the pylon assembly is rotatable to selectively operate the tiltrotor aircraft between a helicopter mode and an airplane mode, a vibration isolator assembly connected to the pylon assembly and the wing including a first vibration isolator configured to isolate vibration in a vertical plane a second vibration isolator configured to isolate vibration in a lateral plane.