A self-compensating fiber optic flow sensor system based on the principle of broadband white-light interferometers and cantilever beam bending is described. The fiber optic sensor system uses two fiber ferrule sensors that are bonded on either side of a cantilever beam to measure the flow rate by monitoring the air-gap changes caused by the bending of the cantilever beam. Cross sensitivity of t...

Crack tip deformations and fracture parameters in functionally graded glass-filled epoxy beams are experimentally evaluated under static and dynamic loading conditions. Beams with unidirectional, monotonic elastic gradients and cracks along the gradient are examined. SEN samples with increasing or decreasing Young’s modulus ahead of the crack tip are studied in symmetric four-point bending and ...

This paper explores the structure, composition, and mechanical properties of porcupine fish spines for the first time. The spine was found to be composed of nanocrystalline hydroxyapatite, protein (collagen), and water using X-ray diffraction, energy-dispersive X-ray spectroscopy, and thermogravimetric analysis. Microstructures have mineralized fibrillar sheets in the longitudinal direction and...

Title of dissertation: ADVANTAGEOUS UTILIZATION OF NONLINEAR PHENOMENA IN MICRO-STRUCTURES AND MACRO-STRUCTURES Andrew James Dick, Doctor of Philosophy, 2007 Dissertation directed by: Professor Balakumar Balachandran and Professor C. Daniel Mote, Jr. Department of Mechanical Engineering Within this work, the nonlinear oscillations of various beam-like structures are studied. Methods are develop...

A voltage regulator is developed to extend the operation range of a electrostatic actuator using a displacement feedback. The feedback actuator system can be used for continuous position tracking of step, ramp, or harmonic voltage signals. The electrostatic actuator is composed of a micro-cantilever beam electrode above a fixed electrode. The voltage difference between the two electrodes is reg...

The atomic force microscope (AFM) has become an essential tool for the measurement of surface characteristics of diverse materials on a microand nanoscale level [1]. The resolution of measurements for the AFM cantilever is related to its vibration sensitivity. Many researchers have much interest in studying the resonant frequency and sensitivity analysis of AFM cantilevers [2 4]. Cracks may be ...

The development of strong, tough, and damage-tolerant ceramics requires nano/microstructure design to utilize toughening mechanisms operating at different length scales. The toughening mechanisms so far known are effective in micro-scale, then, they require the crack extension of more than a few micrometers to increase the fracture resistance. Here, we developed a micro-mechanical test method u...

This study investigated the feasibility of the micro powder blasting technique for the micro fabrication of sensor structures using the Pyrex glass to replace the existing silicon-based acceleration sensor fabrication processes. As the preliminary experiments, the effects of the blasting pressure, the mass flow rate of abrasive and the number of nozzle scanning times on erosion depth of the Pyr...

A working model has been developed which can be used to significantly increase the accuracy of cantilever deflection measurements using optical beam techniques (used in cantilever-based sensors and atomic force microscopes), while simultaneously simplifying their use. By using elementary geometric optics and standard vector analysis it is possible, without any fitted or adjustable parameters, t...