Based on the momentum and continuity equations for ferrofluid under an applied magnetic field, assuming linear behavior for the magnetic material of the ferrofluid, and using carrying current concentric finite wire magnetic field model, the magnetic force was calculated. A modified Reynolds equation is obtained. It is simultaneously solved with the energy equation numerically by the finite diff...

In this study, we investigated the control of the rotation dynamics of an innovative type of rotary micromotors with desired performances by tuning the magnetic interactions among the assembled micro/nanoscale components. The micromotors are made of metallic nanowires as rotors, patterned magnetic nanodisks as bearings and actuated by external electric fields. The magnetic forces for anchoring ...

Applying a magnetic field of o-1 Gs (1 gauss = io~*T) to the heads of pigeons homing from unfamiliar release sites significantly increased the scatter of the birds' vanishing bearings. A magnetic field of 0-3 gauss caused no difference between the orientation of birds wearing coils with either their north or south pole up. But a field of o-6 gauss (equal to that of the Earth) produced a small d...

Abs tmt In this paper aspects of non linear systems and flat control are studied for a specific application of a satellite fine pointing breadboard based on semi active magnetic bearings actuators. Authors propose a complete 6 degrees of freedom mechanical model which describes the system dynamics. A completely non linear and unstable system is obtained leading to implement non linear control l...

Active magnetic bearings are complex mechatronic systems that consist of mechanical, electrical, and software parts, unlike classical rolling bearings. Given the complexity this type system, fault detection is a critical process. This paper presents new easy way to detect faults based on use dictionary machine learning. The was built starting from signatures consisting images obtained signals a...

Cageless ball bearings are often preferred as a back-up bearing for active magnetic to support falling rotor, but the contact between balls of cageless may lead deterioration performance and affect dynamic stability rotor system. Thus, we studied discrete dynamics bearings. First, model is proposed change groove curvature center local outer raceway control velocity achieve dispersion. Combined ...

Fault diagnosis based on vibration signals in active magnetic bearing-rotor systems is an important research topic. However, it difficult to obtain discriminative features represent faults due the nonlinear and non-stationary characteristics of diverse sources failures. Hence, this paper proposes a novel end-to-end learning mechanism multi-sensor data fusion learn fault representation structura...