The present invention provides a method and apparatus for energy absorption and vibrational dampening when attached to a vertical or horizontal structure. According to a first preferred embodiment, the present invention includes a closed housing which may preferably include an internal, curved surface. According to a further preferred embodiment, the present invention may include at least one dampening weight or sphere which may preferably be disposed within the closed housing. According to a further preferred embodiment, the dampening sphere may include internal baffling such as particles having resistance to the flow of the particles within the closed housing.

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 rotor-regulation system includes a rotor comprising a plurality of blades, a mechanically driven hydraulic pump, a rotor drive shaft operable to drive the rotor and the mechanically driven hydraulic pump, and a throttling valve coupled to the mechanically driven hydraulic pump and operable to modulate rotation of the rotor.

It is provided a wind turbine having a modified eigenfrequency, the wind turbine having a tower including a first tower flange arranged at an upper end portion of a top part of the tower; and, an eigenfrequency modifier including a plurality of weights suspended from the first tower flange by a plurality of rigid supports. It is further provided a method of modifying an eigenfrequency of a wind turbine, the method including modifying the eigenfrequency of the wind turbine by suspending a plurality of weights from a first tower flange arranged at an upper end portion of a top part of a tower of the wind turbine using a plurality of rigid supports.

It is provided a wind turbine having a modified eigenfrequency, the wind turbine having a tower including a first tower flange arranged at an upper end portion of a top part of the tower; and, an eigenfrequency modifier including a plurality of weights suspended from the first tower flange by a plurality of rigid supports. It is further provided a method of modifying an eigenfrequency of a wind turbine, the method including modifying the eigenfrequency of the wind turbine by suspending a plurality of weights from a first tower flange arranged at an upper end portion of a top part of a tower of the wind turbine using a plurality of rigid supports.

Method for vibration damping of and vibration damper assembly for semi-submerged or submerged structure, based on separating hydrodynamic added mass from the semi-submerged or submerged structure by means of a vibration damper assembly exhibiting spring and/or damper properties and use the hydrodynamic added mass as a reaction mass in the vibration damper assembly.

Method for vibration damping of and vibration damper assembly for semi-submerged or submerged structure, based on separating hydrodynamic added mass from the semi-submerged or submerged structure by means of a vibration damper assembly exhibiting spring and/or damper properties and use the hydrodynamic added mass as a reaction mass in the vibration damper assembly.

An agricultural machine, the machine comprising: a distributor boom; a sensor for detecting a vibration of the distributor boom; an electronic control device in communication with the sensor; and a mobile mass coupled to the distributor boom and associated with an actuator, the electronic control device, upon detection of a vibration in the distributor boom, configured to actuate the actuator to relocate the mobile mass in the direction of the vibration to be damped with respect to the distributor boom.

Apparatus and methods to reduce unwanted motion in precision instruments are described. An active vibration-isolation system may include a feedback loop that senses motion of an intermediate mass. In noisy environments, where the feedback loop would otherwise fail or provide inadequate isolation, feedforward control can be implemented to sense floor vibrations and reduce motion of the intermediate mass that would otherwise be induced by the floor vibrations. The feedforward control can reduce motion of the intermediate mass to a level that allows the feedback loop to operate satisfactorily.