An active vibration controller includes: a housing; a first magnetic member on the housing, the first magnetic member including a first tip portion extending from a first base end of the first magnetic member and including a first connecting surface extending from the base end on the first tip portion; a movable member including a second magnetic member including a second tip portion extending from a second base end of the second magnetic member and a second connecting surface extending from the second base end on the second tip portion; an exciting coil; a magnetic viscoelastic elastomer having a magnetic viscoelastic property varying according to a magnetic field magnitude between the first and second tip portions, and connects the first connecting surface to the second connecting surface. The first and second tip portions are thinner than the first and second base ends, respectively.

The present invention relates to a dynamic damper control device. A control unit includes a first acceleration sensor configured to obtain a first acceleration of a mass member, a second acceleration sensor configured to obtain a second acceleration of a vibration control target member, and a target amplitude amplification ratio calculating unit configured to calculate a target amplitude amplification ratio of the mass member and the vibration control target member based on the first acceleration and the second acceleration, and is configured to change a magnetic force produced from an electromagnet based on the target amplitude amplification ratio.

An engine mount control apparatus that is an active noise vibration control apparatus according to the present disclosure is characterized by being provided with a housing that has an outer core, an inner core that is disposed inside the outer core, and an electromagnetic coil that is positioned between the outer core and the inner core and by a portion between the outer core and the inner core being filled with a magneto-rheological elastomer containing magnetic particles. The present disclosure enables the maintenance of good static load support performance.

This dynamic damper is provided with a movable part that can be moved by external input, and an excitation coil for generating a magnetic field of an intensity corresponding to a supplied electric current. The movable part is configured to include: first and second magnetic cores in which magnetic paths, which are pathways for the magnetic field generated by the excitation coil, are configured as annular closed magnetic paths; and a magnetic viscous elastomer of which the viscous properties change in accordance with the size of the magnetic field generated by the excitation coil. The magnetic viscous elastomer is arranged so as link at least one location in the first and second magnetic cores and constitutes a closed magnetic path.

This disclosure relates to systems and haptic actuators, and suitably haptic actuation resulting from the response to a magnetic field of magnetic particles within an elastomeric material. Such systems and haptic actuators are useful in structural materials, including as elements of wearables or accessories, as well as in other applications and devices where haptic feedback is desired.

A craft damper (torsion damper) includes a crankshaft (shaft member) to be input with a torsion vibration, a disc member coaxially attached to the crankshaft, a ring-shaped inertia mass body connected to an outer peripheral side of the disc member via a magneto-rheological elastomer member so as to be coaxial with the crankshaft, and an electromagnetic coil for applying a magnetic field to the magneto-rheological elastomer member.

Example devices, systems, and methods for structural health monitoring of composite structures are disclosed. One example method includes attaching a device to an object by fitting the device around the object, where the device includes an enhanced magnetorheological elastomer (MRE) and an elastomer, the enhanced MRE has a folded pattern, the enhanced MRE is embedded in the elastomer, and the device is configured to output a voltage signal generated by the enhanced MRE based on a strain induced on the device in response to deformation. A digital signal is generated based on the voltage signal and using a data processing system, where the data processing system includes a Wheatstone bridge, an amplifier, and an analog-to-digital convertor. A strain value associated with the object is determined based on the digital signal.

An active vibration control device includes: a housing; a movable part including at least one movable mass member; an exciting coil that generates a magnetic field with an intensity corresponding to a current supplied to the exciting coil; a magnetic viscoelastic elastomeric member whose viscoelastic property changes in accordance with a magnitude of the magnetic field generated by the exciting coil; and a support member made of a non-magnetic material. The housing and the movable part are elastically connected with each other by both the magnetic viscoelastic elastomeric member and the support member.

When forces are input to a mount in a plurality of directions, an ECU changes the magnitude of a coil excitation current to change the strength of a magnetic field. At this moment, the elastic force of the mount can be changed in directions in response to the plurality of directions in which the forces are input using a plurality of magnetorheological elastomers (a brim-shaped MRE portion and a cylindrical MRE portion) in which magnetic particles are arranged in different manners.

Exemplary inventive practice provides a structure that is attributed with superior resistance to loading. For example, an inventive structure includes two coaxial axisymmetric (e.g., cylindrical) shells and a granulation-filled matrix material occupying the peripheral space between the shells. According to some inventive embodiments, the granulation-filled matrix material has a loading-responsive matrix (e.g., shear-thickening fluid or highly rate-sensitive polymer) and granules dispersed therein. When the inventive structure encounters pressure loading at its exterior shell, the consistency of the loading-responsive matrix becomes thicker or firmer and thereby promotes, among the granules, interactive mechanisms (e.g., friction and/or arching) that reinforce the granulation-filled matrix material. According to some inventive embodiments, the granulation-filled matrix material has a magnetic-field-responsive matrix and magnetizable granules dispersed therein, and is magnetically fortified via application of a magnetic field (e.g., continuously applied where the matrix is magnetorheological fluid, or temporarily applied where the matrix is rheological fluid containing diamagnetic particles).