A method and an apparatus for isolating a vibration of a positioning device are provided. The apparatus includes a base plate for the positioning device, at least one active bearing element for bearing the base plate on/at a foundation and at least one evaluation and control device. The apparatus includes at least one means for determining a foundation movement-dependent quantity, wherein the active bearing element is controllable by the at least one control and evaluation device on the basis of the foundation movement-dependent quantity.

An electromagnetic-piezoelectric composite vibration control device based on a synchronized switch damping technology is provided. An upper guiding component is installed inside the upper rigid frame, a lower guiding component is installed inside a lower rigid component, a guide rod is nested inside the upper guiding component and the lower guiding component, an upper idler wheel mechanism and a lower idler wheel mechanism are fixedly sleeved on the guide rod and are positioned between the upper guiding component and the lower guiding component respectively, an electromagnetic mechanism is fixedly sleeved outside the guide rod, one end of each piezoelectric cantilever beam is fixed between the upper rigid frame and the lower rigid frame, the other end is arranged between the upper idler wheel mechanism and the lower idler wheel mechanism, and the piezoelectric cantilever beams and the electromagnetic mechanism are connected with a circuit system respectively.

The present invention belongs to the technical fields of civil engineering, smart material and health monitoring, and provides a viscous damper fluid viscosity monitoring device and method based on piezoceramic transducers, comprising piezoceramic transducers, wires, corks, a baffle and a viscous damper. When the fluid viscosity of the viscous damper changes, the energy dissipation of pressure waves during propagation in a fluid will change, and signals received by the piezoceramic transducers will change, so that the viscosity of the fluid in the viscous damper can be calculated by the amplitude change of the signals received. The device of the present invention has a simple structure and accurate monitoring results, and provides a simple and feasible method for real-time monitoring of fluid viscosity of viscous dampers in engineering.

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 control device of a plate-like member 11 includes: a plurality of piezoelectric element actuators 14; at least one piezoelectric element sensor 15; and a control circuit 17 that performs feedback control of operation of the piezoelectric element actuators 14 based on an output voltage of the piezoelectric element sensor 15 so as to suppress vibration of the plate-like member 11. A layout of the piezoelectric element sensor 15 and the piezoelectric element actuators 14 is set such that anti-resonance occurs in an output voltage of the piezoelectric element sensor 15 in a range where the vibration frequency of the plate-like member 11 is equal to or less than a predetermined value. Therefore, generation of noise can be prevented at the frequency. As a result, a gain can be increased at a control target frequency. Therefore, vibration can be suppressed, and noise can be reduced.

A vibration control element includes a nanovoided polymer layer having a first damping coefficient and a first resonance frequency in a first state and a second damping coefficient and a second resonance frequency in a second state, where the first damping coefficient is different from the second damping coefficient and the first resonance frequency is different from the second resonance frequency.

A magnetic geared rotating electrical machine is provided with a stator, a low-speed rotor which includes a plurality of pole pieces arranged in a circumferential direction of the stator and is installed inside the stator, a high-speed rotor which includes a plurality of second magnets as magnets facing the plurality of pole pieces and is installed inside the low-speed rotor, a first piezoelectric element which is provided in each of the plurality of pole pieces and which converts a vibration into an electric signal, and a control unit which is connected to the first piezoelectric element and performs vibration damping of the pole piece on the basis of an output voltage of the first piezoelectric element.

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.

Provided is a sound reduction or vibration damping apparatus that has a new sound control principle where the sound control principle is totally different from a known passive or active sound control apparatus. A sound reduction or vibration damping apparatus 1 includes a mass portion 11, spring portions 12a and 12b placed between the mass portion 11 and a structural member 13, and a control unit 4 for causing the spring constants of the spring portions 12a and 12b to continue changing. The sound reduction or vibration damping apparatus 1 is mounted on the structural member 13 to reduce sound passing through the structural member 13 or sound generated from the structural member, or damp the vibration of the structural member 13.

To solve a problem, for example, in which holding a movable mass becomes difficult because the spring characteristics of a rubber constituting a basis are set low in order to set the characteristic value at a low value. In a first dynamic vibration absorber including a movable mass that is coupled to a vibration damping target member via an MRE as a first elastic member having elastic characteristics variable with a magnetic field, and being capable of varying a vibration characteristic value of the movable mass by controlling the magnetic field, the dynamic vibration absorber has a second elastic member different from the MRE, and the vibration damping target member and the movable mass are elastically-coupled to each other via the second elastic member.