A Tunable Vibration Isolator Using a Magnetorheological Elastomer With a Field Induced Modulus Bias

Abstract

Magnetorheological Elastomers (MRE) are composed of a ferromagnetic filler, micron sized iron particles, in an elastomer matrix. When a magnetic field is applied to an MRE, the iron particles develop a dipole interaction energy, which results in the material displaying a field dependent modulus. MRE materials have received attention in the last decade due in part to their potential application in semi-active vibration isolators. However, compared to MR fluid dampers, few applications of MRE materials have been developed, and no commercial devices are available. This paper describes the development of an MRE based isolator. Unique to this design is the introduction of a field induced modulus bias via a permanent magnet, which can be offset with a current input to the electromagnetic control coil. If the field bias is not significant enough to saturate the iron particles then an appropriately directed input current can also further increase the field induced modulus. Such a Biased Magnetorheological Elastomer (B-MRE) could be useful for applications where the designer wishes to decrease the system stiffness, something that has not been addressed by other MRE based devices.

Investigating new symmetry classes in magnetorheological elastomers: cantilever bending behavior

“…This change in stiffness has been utilized in the design of several tunable/controllable vibration isolation devices [15][16][17][18][19][20][21][22][23][24][25][26][27]. Beyond this work, however, the authors know of no studies of MRE materials that examine their ability to act as remotely powered actuators.…”

“…This change in stiffness has been utilized in the design of several tunable/controllable vibration isolation devices [15][16][17][18][19][20][21][22][23][24][25][26][27].…”

Dynamic shear response of hardversussoft magnetic magnetoactive elastomers

“…For sample A-S, one notices that field dependence of G reaches saturation at μ 0 H sat ~0.07 T. From equations (10) and (11), one expects the maximal change in shear…”

“…Soft polymer matrices have been chosen more recently due to their enhanced relative stiffness change [5,7]. Many researchers have devised dynamic tests that capture the shear behavior in terms of the observed dynamic response [1,3,4,6] and MAEs have been widely used in shearing-mode applications [6][7][8][9][10][11][12][13].…”