An assembly for multi-stage damping comprising a damping unit 20 including a decoupler 36 defining an annular zone 70 surrounding a circular zone 68. The annular zone 70 extends inwardly from an outer ring 38 to define a ring shape for flexing with the circular zone 68 in a first mode 72 to maximize the potential volume of displacement between a first chamber 30 and a second chamber 32. Additionally, the assembly provides for flexing the annular zone 70 independently of the circular zone 68 in a second mode 74 to decrease the potential volume of displacement of the decoupler 36 between the first chamber 30 and the second chamber 32. The decoupler 36 includes a plurality of rings 38, 46, 54 extending axially from a first surface 40 and a second surface 42 for defining an axial travel limit for the annular zone 70.

A conformal coating system for a pipeline consists of an adhesive comprising a three-dimensional particle dispersed therein and a plurality of sensors. The adhesive is applied to an outside layer of a section of the pipeline. The sensors are dispersed along the length of the pipeline and detect an amplitude and frequency of a waveform of a force acting upon the section of the pipeline and initiate a controlled response by the particles. The controlled response is based on the amplitude and frequency of the waveform.

Adhesive damping systems are described. A damping system for reducing the effects on a substrate caused by a disruption in the substrate environment includes an adhesive having a plurality of three-dimensional particles dispersed therein. The particles are configured to provide a controlled response to an applied force field. The system further includes a sensor which measures an amplitude and frequency spectrum of the disruption. In a use configuration, the sensor determines the amplitude and frequency spectrum of the disruption received by the substrate; and the applied force field is dependent on the amplitude and frequency spectrum of the disruption.

A system for modifying a stiffness of a structure of a vehicle using vibrational energy of the vehicle includes a variable-stiffness layer, having a selectively controllable Young's modulus, attached to the structure, and a conversion layer, coupled to the variable-stiffness layer, the conversion layer configured to convert vibrational energy from the structure into electrical energy, and to supply the electrical energy to the variable-stiffness layer to adjust a stiffness of the variable-stiffness layer.

A vibratory structure includes: a vibratory body; piezoelectric elements mounted to a surface of the vibratory body; and resonant circuits configured to operate in response to electrical energy generated by the piezoelectric elements so as to cause a change in a damping characteristic of the vibratory body at a target frequency upon vibration of the vibratory body, and assuming that an axis of the vibratory body in a direction of principal strains is a reference axis, each of the piezoelectric elements is fixed at fixing regions at different locations in the direction of the reference axis.

A vibration reduction system includes a base, a carrier element, and a plurality of actuator systems extending between the base and the carrier element, the plurality of actuator systems arranged to apply forces to the carrier element in multiple axes to reduce vibration of the carrier element, each actuator system of the plurality of actuator systems including a pneumatic actuator and an electric actuator.

According to the present invention there is provided a vibration control system comprising: a resonator comprising: a base attachable to an external body; a control element; and one or more connection elements each having a resilient portion, wherein the control element is resiliently connected to the base by the one or more connection elements such that relative movement between the control element and the base is facilitated by the one or more connection elements; and a driving mechanism, wherein the resonator comprises at least a part of the driving mechanism.

Disclosed herein is an adaptive system that converts vibration in mechanical structures into electrical energy using a transducer having piezoelectric properties. The electrical energy generated is then converted into heat loss in an electrical circuit comprising: an adaptive inductance that autonomously changes its value by comparing the phase difference of the vibration velocity and the current flowing through the shunt circuit; a resistance to convert electrical energy into heat loss; and a synthetic negative capacitance to enhance the vibration attenuation.

Disclosed is a multi-modal and multi-degree-of-freedom piezoelectric active vibration isolation platform and a working method therefor. The piezoelectric active vibration isolation platform includes an upper platform, a lower platform, a control module, and four vibration isolation modules, where the vibration isolation module includes a passive vibration isolation unit and an active vibration isolation unit; the passive vibration isolation unit includes an upper connector, a lower connector, a cross Hooke hinge, and a first acceleration sensor; the active vibration isolation unit includes a fixed beam, a pre-tightening bolt, a second acceleration sensor, and a driving component; the platform can provide active vibration isolation for the longitudinal (axial) vibration and the bending vibration in any radial direction of a vibration isolation object, and has the advantages of fast response, resistance to electromagnetic interference, and light weight.

A force generator for introducing vibrational forces into a structure for vibration control of the structure includes an inertial mass, at least one actuator for generating a vibratory movement of the inertial mass relative to the structure, and a drive circuit constructed from components for driving the at least one actuator. At least part of the inertial mass is formed by one component of the drive circuit.