This research focused on improving the control and sensing of electrostatically actuated, large deflection bimorph beams for optical beam steering. Current iterations of designs utilize a ‘zipper’ beam and have demonstrated large deflection angles. However, with these devices precise control and deflection measurements can be difficult to achieve. Through using segmented bias channels of doped ...
A device composed of a piezoelectric bimorph cantilever and a water electrolysis device was fabricated to realize piezoelectrochemical hydrogen production. The obvious output of the hydrogen and oxygen through application of a mechanical vibration of ~0.07 N and ~46.2 Hz was observed. This method provides a cost-effective, recyclable, environment-friendly and simple way to directly split water ...
I. G. Foulds,
INTRODUCTION: Micro Electro Mechanical Systems (MEMS) are fabricated with an in-plane fabrication technology. Out-of-plane structures can be designed to be assembled to provide thermal and electrical isolation from the substrate [1 -3]. These isolations can potentially improve the performance of a range of MEMS devices by decreasing any unwanted coupling effects or parasitic losses from the dev...
Piezoelectric bimorph elements are versatile and inexpensive electromechanical transducers which may be used to construct fast mechanical stimulators and finely controlled micromanipulators. The mechanical stimulators described provide continuously graded displacements ranging from nanometers to about a millimeter, or forces equivalent to 0-7 g. Appropriately designed units can produce small st...
Stephen P. Beeby,
This paper reports a bimorph piezoelectric vibration energy harvester incorporating multiple PZT layers. The advantage of a multi-layer generator is that it produces a higher power than a single-layer generator having the same total thickness. In addition, a lower voltage is required to polarize a multi-layer generator reducing the risk of breakdown during polarization. Moreover, the optimum re...
Dan O. Popa,
Byoung Hun Kang,
John T. Wen,
Harry E. Stephanou,
Thermal bimorphs are a popular actuation technology in MEMS (Micro-Electro-Mechanical Systems). Their operating principle is based on differential thermal expansion induced by Joule heating. Thermal bimorphs, and other thermal flexture actuators have been used in many applications, from microgrippers, to micro-optical mirrors. In most cases openloop control is used due to difficulties in fabric...
A multi-walled carbon nanotube (MWNT) bimorph nanoactuator has been modeled, fabricated and characterized. A thin aluminum film was uniformly deposited on the sidewalls of MWNTs using a pulsed laser deposition method to create the bimorph nanostructure. For a temperature change from 290 to 690 K with measured dimensions of 100 +/- 20 nm for the MWNT diameter, 40 +/- 10 nm for the Al thickness, ...
We apply robust control techniques to an adaptive optics system including a dynamic model of the deformable mirror. The dynamic model of the mirror is a modification of the usual plate equation. We propose also a state-space approach to model the turbulent phase. A continuous time control of our model is suggested, taking into account the frequential behavior of the turbulent phase. An H(infini...
Karl F. Böhringer,
John W. Suh,
Gregory T. A. Kovacs,
Microelectromechanical system (MEMS) technology promises to improve performance of future spacecraft components while reducing mass, cost, and manufacture time. Arrays of microcilia actuators offer a lightweight alternative to conventional docking systems for miniature satellites. Instead of mechanical guiding structures, such a system uses a surface tiled with MEMS actuators to guide the satel...