We demonstrate five-degree-of-freedom (5-DOF) wireless magnetic control of a fully untethered microrobot with a magnetic steering system we call OctoMag. Although only occupying a single hemisphere, this system is capable of isotropically applying forces on the order of 1–40 μN with unrestricted control of the 2 orienting DOF. These capabilities are enabled through the use of soft-magnetic-core...

The paper presents results of validation of the anhysteretic magnetization model for a soft amorphous alloy with significant perpendicular anisotropy. The validation was carried out for the Jiles-Atherton model with Ramesh extension considering anisotropy. Due to the fact that it is difficult to measure anhysteretic magnetization directly, the soft magnetic core with negligible hysteresis was u...

Low temperature fabrication of Al2O3-polyimide composite substrates was carried out by an aerosol deposition process using a mixture of Al2O3 and polyimide starting powders. The microstructures and dielectric properties of the composite thick films in relation to their Al2O3 contents were characterized by X-ray diffraction analysis. As a result, the crystallite size of α-Al2O3 calculated from S...

Soft magnetic composite (SMC) materials are especially suitable for construction of electrical machines with complex structures and three-dimensional (3-D) magnetic fluxes. In the design and optimization of such 3-D flux machines, the 3-D vector magnetic properties of magnetic materials should be properly determined, modeled and applied for accurate calculation of the magnetic field distributio...

The complete elastic tensor of Fe0.94O (wüstite) has been determined to 10 GPa using acoustic interferometry at GHz frequencies inside a diamond-anvil cell. The soft mode (C44) elastic constant of FeO is reduced by 20% over the experimental pressure range. An unusual discontinuity in the pressure derivatives of C11 and C12 at 4.7+/-0.2 GPa corresponds to the pressure at which the onset of a mag...

Powder neutron diffraction and magnetic susceptibility measurements at 10-300 K have been used to determine the crystal and magnetic structures of brownmillerite type Ca(2)Cr(2)O(5), which was obtained by reduction of the high pressure phase CaCrO(3) through hard-soft chemistry. The ambient temperature crystal structure of Ca(2)Cr(2)O(5) is refined in space group I2mb and the unusual tetrahedra...

the brass tubes with foam cores of alsi7sic3, alsi7sic3fe1 and alsi7sic3fe3 were produced as the crush-boxes with circle and square cross-section. then axial compressive behavior and energy absorption capability of the foam-filled tubes were investigated during the quasi-static progressive plastic buckling. the uniaxial compressive stress–strain curves of the foam-filled brass tubes exhibited t...

We construct spherical, hydrostatic models of dense molecular cores and Bok globules consisting of two distinct, spatially separate gas components: a central, isothermal region surrounded by a negative-index, polytropic envelope. The clouds are supported against their own self-gravity by a combination of thermal, mean magnetic, and turbulent wave pressure. The latter two are included by allowin...