Hofer E.P. – TechConnect Briefs

Levitation of a Charged Microdroplet

Schildknecht A., Hofer E.P., University of Ulm, DE

A new method for levitation of a charged microdroplet is presented. The feedback-control consists of high-speed camera, flatness based follow-up controller and high-voltage amplifier.

Miniaturized High Speed Visualization Setup for the Diagnostics of Dynamical Processes in Microsystems

Brugger H., Maier C., Hofer E.P., University of Ulm, DE

For the real time visualization of the dynamics of MEMS it is often inevitable to use high speed camera systems because of the optical enlargement. The micro diagnostic system MinVis, which consists of a miniaturized [...]

Microflows with Moving Boundaries: Experiment and Simulation

Maier C., Hofer E.P., University of Ulm, DE

Surface forces and capillary effects can play a dominant role in fluidic microsystems. Therefore it is crucial for simulations to use accurate numerical approaches [1]. Furthermore experimental data gained from such surface dominated systems can [...]

Impact of Microdrops on Solid Surfaces for DNA-Synthesis

Maier C., aus der Wiesche S., Hofer E.P., University of Ulm, DE

The miniaturization of chemical synthesis procedures and their integration in complex microfluidic systems is highly interesting both commercially and scientifically. Here, dosing of microdrops for activation or passivation with high accuracy on a substrate or [...]

Dynamics in a Thermal Ink Jet: A Model for Identification and Simulation

Rembe C., aus der Wiesche S., Hofer E.P., University of Ulm, DE

In this paper a newly developed model for identification and simulation of dynamic phenomena in a thermal ink jet is presented. As a result of the modeling the calculation of the pressure propagation in the [...]

Dynamics in Microfluidic Systems with Microheaters

aus der Wiesche S., Rembe C., Maier C., Hofer E.P., University of Ulm, DE

The physics of nucleation, boiling, bubble growth and collapse in thermal microactuators will be presented. The boiling process exhibits an equivalence to a phase transition of second order and this leads, in contrast to classical [...]

Model Based Identification as a New Tool to Extract Physical Parameters of Microactuators from Measurements with Error Bounds

Rembe C., Hofer E.P., Tibken B., University of Ulm, DE

Model based evaluation of high speed cinematographic image sequences is demonstrated for a microrelay which was manufactured using the LIGA technology. The measurements of the microrelay have been performed with an experimental setup based on [...]