Digital Commons Network^™

A Review Of Tunable Wavelength Selectivity Of Metamaterials In Near-Field And Far-Field Radiative Thermal Transport, Yanpei Tian, Alok Ghanekar, Matt Ricci, Mikhail Hyde, Otto J. Gregory, Yi Zheng

Mechanical, Industrial & Systems Engineering Faculty Publications

Radiative thermal transport of metamaterials has begun to play a significant role in thermal science and has great engineering applications. When the key features of structures become comparable to the thermal wavelength at a particular temperature, a narrowband or wideband of wavelengths can be created or shifted in both the emission and reflection spectrum of nanoscale metamaterials. Due to the near-field effect, the phenomena of radiative wavelength selectivity become significant. These effects show strong promise for applications in thermophotovoltaic energy harvesting, nanoscale biosensing, and increased energy efficiency through radiative cooling in the near future. This review paper summarizes the recent …

A System Combining Force And Vision Sensing For Automated Screw Removal On Laptops, Nicholas M. Difilippo, Musa Jouaneh

Mechanical, Industrial & Systems Engineering Faculty Publications

This brief investigates the performance of an automated robotic system, which uses a combination of vision and force sensing to remove screws from the back of laptops. This robotic system uses two webcams, one that is fixed over the robot and the other mounted on the robot, as well as a sensor-equipped (SE) screwdriver. Experimental studies were conducted to test the performance of the SE screwdriver and vision system. The parameters that were varied included the internal brightness settings on the webcams, the method in which the workspace was illuminated, and color of the laptop case. A localized light source …

An Inexpensive Microfluidic Pdms Chip For Visual Detection Of Biofilm-Forming Bacteria, Rico Kolossa, Assem Abolmaaty, D.M.L. Meyer, Zongqin Zhang

Mechanical, Industrial & Systems Engineering Faculty Publications

Aims: Design and assembly of an inexpensive microfluidic PDMS chip for visual detection of cell adhesion and biofilm formation.

Study Design: Three different styles of microchannels (2.6, 5.0, and 11.5 μl volumes) were designed, fabricated and tested for adhesion and biofilm formation in a microfluidic system. The pressure drop measurements system includes a bio-Ferrograph connected to the PDMS microchannel via a syringe and a pressure transducer.

Methodology: Microfluidic chips were fabricated using Polydimethylsiloxane (PDMS) by means of soft lithography. Different cell densities of E.coli K12 cells were introduced to investigate adhesion and biofilm formation at different time …

Lead-Free Solder Pull-Off Stress Comparison Of A Novel Bump Pull Method With Conventional Hot/Cold Bump Pull Methods, Gregory A. Turner, D.M.L. Meyer

Mechanical, Industrial & Systems Engineering Faculty Publications

A novel method for directly testing the adhesion strength of three lead-free solders was developed and compared with conventional methods. The Isotraction Bump Pull method utilizes a combination of favorable qualities of the Cold and Hot Bump Pull tests. Solder bumps were generated onto copper printed circuit board substrates using an in-house-fabricated solder bump-on-demand generator. The method uses polymer epoxy to encapsulate solder bumps under uniform tractions, and tested under tension for pull-off stresses. Maximum pull-off stresses for the novel method are: 18MPa (Sn-3.5Ag), 16MPa (SAC 305) and 22MPa (Sn-0.7Cu) and fall at the low end in the literature comparisons. …

A Minimal Mechanics Model For Mechanosensing Of Substrate Rigidity Gradient In Durotaxis, Bahador Marzban, Xin Yi, Hongyan Yuan

Mechanical, Industrial & Systems Engineering Faculty Publications

Durotaxis refers to the phenomenon in which cells can sense the spatial gradient of the substrate rigidity in the process of cell migration. A conceptual two-part theory consisting of the focal adhesion force generation and mechanotransduction has been proposed previously by Lo et al. to explain the mechanism underlying durotaxis. In the present work, we are concerned with the first part of the theory: how exactly is the larger focal adhesion force generated in the part of the cell adhering to the stiffer region of the substrate? Using a simple elasticity model and by assuming the cell adheres to the …

Wear Of Ultra High Molecular Weight Polyethylene Against Synthetic Sapphire As Bearing Coating For Total Joint Replacements, Kevin D. Gemmell Jr., D.M.L. Meyer

Mechanical, Industrial & Systems Engineering Faculty Publications

Materials commonly found in hip replacements are a polymer paired with metals or alloys. Tribological behavior of polyethylene bearing surfaces against synthetic sapphire are compared against other bearing combinations to evaluate sapphire as a viable means to lower the incidence of revision surgery by mitigating production of wear debris. Sapphire disks against polyethylene plates were tested utilizing a tribometer. The polyethylene wear rate was found to be 22.6mm³ per year, less than the 40-80mm³ per year typically found in traditional hip replacements. A power law function is presented correlating a decreasing friction coefficient as polyethylene volume loss increases …