A vibration suppression unit for an aircraft comprising a vibration control frame adapted to be mounted to the aircraft and to rotate about a central axis, a first motor configured to rotate the vibration control frame about the central axis, a second motor configured to rotate a first and second center of mass about a first and second axis or rotation, a third motor configured to adjust a variable distance between the first and second centers of mass and the first and second axis of rotation, respectively, and a controller for receiving input signals and outputting command signals to the first, second and third motors.

A device for damping vibrations in a structure including a first (or inner) element rotatably mounted around a rotational axis and a second (or outer) element rotatably mounted around said rotational axis. A radius (R1) of a circle portion delimitating the first element with respect to the rotational axis, being smaller than a radius (r2) of a circle portion delimitating the second element with respect to the rotational axis.

An added inertia resonant system (12) for a power toothbrush (10) comprises a drive shaft (16), a drive system (22), and at least one inertial weight member (24). The drive shaft (16) has a principal axis (26) that defines a center of rotation. The drive system (22) imparts a reciprocating motion to the drive shaft (16) about the principal axis (26). The at least one inertial weight member (24) couples to the drive shaft (16) and comprises a planar material having a complex shape balanced along an x-, y- and z-axis to enable the drive system (22) to achieve low power, high amplitude motion of the drive shaft (16) when placed under user loading. A method for providing added inertia in a resonant system for a power toothbrush is also disclosed.

An added inertia resonant system (12) for a power toothbrush (10) comprises a drive shaft (16), a drive system (22), and at least one inertial weight member (24). The drive shaft (16) has a principal axis (26) that defines a center of rotation. The drive system (22) imparts a reciprocating motion to the drive shaft (16) about the principal axis (26). The at least one inertial weight member (24) couples to the drive shaft (16) and comprises a planar material having a complex shape balanced along an x-, y- and z-axis to enable the drive system (22) to achieve low power, high amplitude motion of the drive shaft (16) when placed under user loading. A method for providing added inertia in a resonant system for a power toothbrush is also disclosed.

A highly-efficient new-energy vibration controller integrating passive, semi-active and active control, including a multi-cavity beam, a battery assembly, a wound magnetic device, a damping piezoelectric device and an inertia mass assembly. The wound magnetic device includes a connecting rod, an electromagnetic wire wound on a bottom end of the connecting rod and a magnetic box arranged at a bottom of the inertia mass assembly. A top end of the connecting rod is fixedly connected to a bottom of the multi-cavity beam. The bottom end of the connecting rod passes through a center through hole of the inertia mass assembly and arranged in the magnetic box. The magnetic box is provided with a magnetic field. The damping piezoelectric device is sleevedly arranged on an outer wall of the connecting rod. The damping piezoelectric device and the wound magnetic device are both electrically connected to the battery assembly.

A highly-efficient new-energy vibration controller integrating passive, semi-active and active control, including a multi-cavity beam, a battery assembly, a wound magnetic device, a damping piezoelectric device and an inertia mass assembly. The wound magnetic device includes a connecting rod, an electromagnetic wire wound on a bottom end of the connecting rod and a magnetic box arranged at a bottom of the inertia mass assembly. A top end of the connecting rod is fixedly connected to a bottom of the multi-cavity beam. The bottom end of the connecting rod passes through a center through hole of the inertia mass assembly and arranged in the magnetic box. The magnetic box is provided with a magnetic field. The damping piezoelectric device is sleevedly arranged on an outer wall of the connecting rod. The damping piezoelectric device and the wound magnetic device are both electrically connected to the battery assembly.

A vibration suppression unit for an aircraft comprising a mass having a center of mass, a first rotor, a second rotor, a first coupling between the first rotor and the mass, a second coupling between the second rotor and the mass, the first and second couplings having first and second coupling centers offset perpendicularly from a central axis of rotation by different radial distances and offset in axially from the center of mass with respect to the central axis by different axial distances, the first and second coupling centers having a selectively variable displacement angle defined by the angle between lines extending between the central axis of rotation and the first coupling center and the second coupling center, respectively, wherein the first rotor and the second rotor are controllable to produce a vibration control force vector having a controllable magnitude and frequency about the central axis.

A multi-chamber internally damped tuned vibration absorber includes a mass having internal chambers that house damping members for dissipating vibrational motion of the mass. Guide members pass through the internal chambers and guide movement of the mass. An attachment member attaches the guide members to a structure to attenuate vibrations of the structure.

A multi-chamber internally damped tuned vibration absorber includes a mass having internal chambers that house damping members for dissipating vibrational motion of the mass. Guide members pass through the internal chambers and guide movement of the mass. An attachment member attaches the guide members to a structure to attenuate vibrations of the structure.

Circular force generator devices (100), systems, and methods for damping vibrations which include two complementary rotor assemblies (110, 120) that are rotatable together about a common shaft (102) but that have an adjustable rotational position (P1, P2) with respect to one another such that a significant reduction in rotor inertia and bearing drag relative to conventional CFG configurations is provided. The present architecture creates virtually zero rotating moment.