3D numerical modeling and experimental validation of diamagnetic levitated suspension in the static field

Diamagnetic levitation principle opens to promising solutions for innovative powerless and low stiffness suspension applicable to many technological fields. The peculiarities of diamagnetic suspension make this design solution very attractive for some applications such as microdevices and energy harvesters. Low stiffness and powerless functioning are the most appreciable characteristics of this kind of suspension, despite their force-displacement curve is generally hard to predict and strongly nonlinear. The modeling complexity resides in the preliminary prediction of magnetic field distribution and in the calculation of diamagnetic forces as function of the levitation height. This work introduces a modeling approach for calculating the levitation height of a parameterized diamagnetic suspension composed of a ground of permanent magnets and a levitating mass made of pyrolytic graphite. The numerical discretization approach is used and the predicted values are compared with experiments providing good agreement between result

Rigid body dynamics of diamagnetically levitating graphite resonators

Diamagnetic levitation is a promising technique for realizing resonant sensors and energy harvesters, since it offers thermal and mechanical isolation from the environment at zero power. To advance the application of diamagnetically levitating resonators, it is important to characterize their dynamics in the presence of both magnetic and gravitational fields. Here we experimentally actuate and measure rigid body modes of a diamagnetically levitating graphite plate. We numerically calculate the magnetic field and determine the influence of magnetic force on the resonance frequencies of the levitating plate. By analyzing damping mechanisms, we conclude that eddy current damping dominates dissipation in mm-sized plates. We use finite element simulations to model eddy current damping and find close agreement with experimental results. We also study the size-dependent Q-factors (Qs) of diamagnetically levitating plates and show that Qs above 100 million are theoretically attainable by reducing the size of the diamagnetic resonator down to microscale, making these systems of interest for next generation low-noise resonant sensors and oscillators.Comment: 6 pages, 4 figure

On the Static Pull-In of Tilting Actuation in Electromagnetically Levitating Hybrid Micro-Actuator: Theory and Experiment

This work presents the results of the experimental and theoretical study of the static pull-in of tilting actuation executed by a hybrid levitation micro-actuator (HLMA) based on the combination of inductive levitation and electrostatic actuation. A semi-analytical model to study such a pull-in phenomenon is developed, for the first time, as a result of using the qualitative technique based on the Lagrangian approach to analyze inductive contactless suspensions and a recent progress in the calculation of mutual inductance and force between two circular filaments. The obtained non-linear model, accounting for two degrees of freedom of the actuator, allows us to predict accurately the static pull-in displacement and voltage. The results of modeling were verified experimentally and agree well with measurements