Current controlled piezoelectric beams have been very popular recently due to the substantial reduction of hysteresis between the input and output. Even though there are many different PDE models for the voltage and charge controlled piezoelectric beams, there is no thoroughly derived PDE model in the literature for current controlled piezoelectric beams. A variational approach is utilized to d...

Electrowetting on dielectric and dielectrophoretic electromechanical mechanisms dominate microfluidic actuation in the low- and high-frequency limits, respectively. The frequency-dependent relationship between these two mechanisms has been clarified by the Maxwell stress tensor and a simple RC circuit model. In this paper, we report extensive height-of-rise measurements obtained with vertical, ...

A coplanar waveguide (CPW) single-pole double-throw (SPDT) X-band RF MEMS switch that can be actuated between states by applying a single voltage is introduced. Since a signal can be transmitted to one of the output ports without biasing, this has the potential to reduce the complexity of the required biasing network. The switch consists of a series and a shunt capacitive MEMS switch separated ...

An inkjet nozzle with double piezo transducers has been designed, which is different from conventional inkjet nozzles. The body of the nozzle which is fabricated by precision machining techniques is made from transparent acrylic material to visualize the flow inside the nozzle. The piezoelectric actuators are activated by a voltage amplifier which generates high-voltage bipolar waveforms. The k...

The effect of flexibility and initial curvature of moving plates in parallel-plate MEMS capacitors are investigated. A parallel-plate-based MEMS tunable capacitor with extended tunability and linear capacitance-voltage (C-V) response is introduced. The design combines the flexibility and curvature of the electrode with an array of mechanical stoppers to increase the overall stiffness of the dev...

A piezoelectric dispenser has been fabricated based on the idea of a piezoelectric-metal-cavity (PMC) actuator. The PMC actuator consists of a metal ring sandwiched between two identical piezoelectric unimorphs. The radial contraction of the piezoelectric ceramic is converted into a flextensional motion of the unimorph, causing a large flexural displacement in the center part of the actuator. W...

Nanosystems operating in liquid media may suffer from random Brownian motion due to thermal fluctuations. Biomolecular motors exploit these random fluctuations to generate a controllable directed movement. Inspired by nature, we proposed and realized a nano-system based on Brownian motion of nanobeads for linear transport in microfluidic channels. The channels limit the degree-of-freedom of the...

This paper theoretically analyzes a dielectric elastomer tube actuator DETA . Subject to a voltage difference between the inner and outer surfaces, the actuator reduces in thickness and expands in length, so that the same voltage will induce an even higher electric field. This positive feedback may cause the actuator to thin down drastically, resulting in electrical breakdown. We obtain an anal...

A recent design of deformable lens mimics the human eye, adjusting its focal length in response to muscle-like actuation. The artificial muscle is a membrane of a dielectric elastomer subject to a voltage. Here, we calculate the coupled and inhomogeneous deformation of the lens and the dielectric elastomer actuator by formulating a nonlinear boundary-value problem. We characterize the strain-st...

The pull-in voltage of a single-side anchored freestanding beam, under lateral deflection, has been investigated for application as a dc voltage reference. Two sets of electrodes, alongside the tip, are used for parallel-plate type of electrostatic actuation of the 200 m long beam in the plane of the wafer. Another set of buried electrodes is aligned with the plate electrode at the free-standin...