Abstract: An active tuned vibration absorber (100) is disclosed for reducing vibrations in a structure, the vibration absorber comprising: a mount (104) for attachment to the structure; a moveable mass (106); a spring arrangement (108) connected between the mass and the mount; an actuator arrangement (110) for applying a force between the mass and the mount; a first sensor (112) for providing a first measurement indicative of a force exerted between the structure and the mount; a second sensor (114) for providing a second measurement indicative of an acceleration of the structure at or proximate to the mount; and a control system (116) for generating an actuator driving signal for driving the actuator using the first and second measurement, wherein the control system is operable to generate the actuator driving signal to cause the first measurement and second measurement to conform to a target relationship.

Abstract: An active tuned vibration absorber (100) is disclosed for reducing vibrations in a structure, the vibration absorber comprising: a mount (104) for attachment to the structure; a moveable mass (106); a spring arrangement (108) connected between the mass and the mount; an actuator arrangement (110) for applying a force between the mass and the mount; a first sensor (112) for providing a first measurement indicative of a force exerted between the structure and the mount; a second sensor (114) for providing a second measurement indicative of an acceleration of the structure at or proximate to the mount; and a control system (116) for generating an actuator driving signal for driving the actuator using the first and second measurement, wherein the control system is operable to generate the actuator driving signal to cause the first measurement and second measurement to conform to a target relationship.

Abstract: An inertial actuator assembly comprises an actuator chassis adapted to be secured in use to a structure subject in use to external vibration forces, a proof mass (ma) supported with respect to the chassis by a proof mass resilient means, and a force generating transducer means acting between the chassis and the proof mass for subjecting in use the proof mass to a force (fa) applied relative to the chassis, a controller arranged to control in use the excitation of the transducer means, wherein the assembly comprises a feedback means H(j?) responsive to a measurement of the displacement (x) of the proof mass relative to the chassis, the controller being arranged to modify the excitation of the force generating transducer means in response to a feedback signal from the feedback means. The feedback signal may be proportional to the displacement, the integral of the displacement, the derivative of the displacement, or to any combination of these.