The Preisach hysteresis model has been adopted extensively in magnetic and smart materialbased systems. Fidelity of the model hinges on accurate identification of the Preisach density function. Existing work on the identification of the density function usually involves applying an input that provides sufficient excitation and measuring a large set of output data. In this paper, we propose a no...

Arrays of electrostatic MEMS actuators have been fabricated using a multi-layer SCREAM (Single-Crystal Reactive Etching and Metallization) process. The high aspect ratio single-crystal silicon (SCS) devices consist of released, torsionally suspended grids with tips. Experiments and calculations show that the actuator array is strong enough to move macroscopic parts. An individual actuator can g...

This paper presents the development of piezoelectric artificial cochlear (P-AC) capable of analyzing incoming acoustic or mechanical signals without external power source. The P-AC consists of membrane part and package part. The package part provides liquid environment through which the incoming signal is transmitted to membrane part. The membrane part responds to the transmitted signal and loc...

We describe the engineering of a hybrid fluidics platform for a chip-based biosensor system that combines high-performance microfluidics components with powerful, yet compact, millimeter-scale pump and valve actuators. The microfluidics system includes channels, valveless diffuser-based pumps, and pinch-valves that are cast into a poly(dimethylsiloxane) (PDMS) membrane and packaged along with t...

With the vast potential of micro-electro-mechanical systems (MEMS) technology, the reliability is essential for the successful applications of microdevices. Polycrystalline silicon is one of the most often used structural materials in microdevices. Tension testing for fatigue life of this material has been investigated since past years. This paper presents a micro-actuatorbased bending testing ...

Paraffin wax has been exploited in microactuators because it exhibits a volumetric expansion of ∼15%, at around its melting point. In order to nderstand paraffin wax actuation, for the first time, the melting process has been investigated using a combination of analytical modelling (using tefan’s problem and Neumann’s solution), finite element method (FEM) simulations and actuation data from me...

The serviceability of microfluidics-based instrumentation including 'lab-on-a-chip' systems critically depends on control of fluid motion. We are reporting here an alternative approach to microfluidics based upon the micromanipulation of discrete droplets of aqueous electrolyte by electrowetting. Using a simple open structure, consisting of two sets of opposing planar electrodes fabricated on g...

We demonstrate the controlled rotation and torque generated by uniaxial magnetic microactuators formed by two bound superparamagnetic particles in a fluid. The torque and rotation are precisely controlled by rotating magnetic fields, generated by an external electromagnet or by on-chip current wires. We present the magnetic energy equations and the equations of motion for two-particle microactu...

In this paper, two different piezoelectric microactuator designs are studied. The corresponding devices were designed for optimal in-plane displacements and different high flexibilities, proven by electrical and optical characterization. Both actuators presented two dominant vibrational modes in the frequency range below 1 MHz: an out-of-plane bending and an in-plane extensional mode. Neverthel...

This paper reports a method that enables real-time displacement monitoring and control of micromachined resonant-type actuators using wireless radiofrequency (RF). The method is applied to an out-of-plane, spiral-coil microactuator based on shape-memory-alloy (SMA). The SMA spiral coil forms an inductor-capacitor resonant circuit that is excited using external RF magnetic fields to thermally ac...