In this paper, we analyze the effect of stress-fiber inclusion on the stiffness of an actin random network. To do this, use a discrete random network model to analyze the elastic response of this system in terms of apparent Young’s modulus. First, we showed that for a flat-ended cylindrical AFM indenter the total indentation force has a linear relation with the indentation depth and the indente...

In vitro, animal cells are mostly cultured on a gel substrate. It was recently shown that substrate stiffness affects cellular behaviors in a significant way, including adhesion, differentiation, and migration. Therefore, an accurate method is needed to characterize the modulus of the substrate. In situ microscopic measurements of the gel substrate modulus are based on Hertz contact mechanics, ...

Depth from defocus (DfD) and stereo matching are two most studied passive depth sensing schemes. The techniques are essentially complementary: DfD can robustly handle repetitive textures that are problematic for stereo matching whereas stereo matching is insensitive to defocus blurs and can handle large depth range. In this paper, we present a unified learning-based technique to conduct hybrid ...

Indentation techniques for assessing fracture toughness are attractive due to the simplicity and expediency of experiments, and because they potentially allow the characterization of both local and bulk fracture properties. Unfortunately, rarely have such techniques been proven to give accurate fracture toughness values. This is a concern, as such techniques are seeing increasing usage in the s...

A study has been made of the deformation field in plane-strain indentation of metals with a flat punch. Deformation field parameters such as velocity and strain rate have been measured using the technique of particle image velocimetry. For this purpose, images of the indentation region were recorded in situ during the deformation process, and motion of ‘asperities’ specially introduced onto a s...

A systematic study of the mechanical deformation and failure of transparent ceramic aluminum oxynitride (AlON) has been conducted using a depth-sensitive nanoindentation technique combined with transmission electron microscopy (TEM) and Raman spectroscopy. Although discrete displacement bursts appear in the load–depth profiles at high applied forces, a detectable high-pressure phase transition ...

A novel noncontact indentation system with the combination of an air jet and optical coherence tomography (OCT) was presented in this paper for the quantitative measurement of the mechanical properties of soft tissues. The key idea of this method is to use a pressure-controlled air jet as an indenter to compress the soft tissue in a noncontact way and utilize the OCT signals to extract the defo...

Planar accelerating millimeter-wave structures have been studied during the last few years at Argonne National Laboratory in collaboration with Technical University of Berlin. The cavity structures are intended to be manufactured by using x-ray lithography microfabrication technology. A complete structure consists of two identical planar half structures put together face-to-face. Since microfab...

A new stiffness measurement method is proposed that utilizes the lateral deformation profile of an object under indentation. The system consists of a force measurement module between a pair of equidistant touch sensing modules. Unique feature of the method is that by adjusting the touch module separation, indenter protrusion, and spring constant of the force sensing module, one can choose a des...