Nanoscale Measurement Techniques of Three-Dimensional Ferroelectric Polarization Using Scanning Nonlinear Dielectric Microscopy

Surface measurement using three-dimensional stylus instruments is a relatively new technique that offers numerous advantages over more traditional profilometry methods. The information generated is, unlike profile measurement, less subjective and more statistical providing additional insight into the surface structure. One application of surface measurement that has encountered problems when using the profilometry method is that of grinding wheel characterisation. The wheel surface texture (topography) and the conditions under which it is generated have a profound effect upon the grinding performance as characterised by the grinding forces, power consumption, temperature, and surface integrity of components. A detailed knowledge of the nature of the topography of the grinding wheel would provide further insight into surface interactions between the wheel and workpiece as well as enabling improved control of the grinding process in general. In this paper four diamond grinding wheels of 91 and 181 micron grit size were subjected to differing dressing conditions to produce varying final wheel topographies. Three-dimensional surface measurement techniques were employed to quantitatively characterise the topographic change and provide an aerial estimation of the number of cutting grains. The results demonstrate that the techniques can distinguish between a worn and dressed wheel. In addition, the parametric values generated from the various surfaces can aid the user in determining when re-dressing is required.

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Three-dimensional Force Perception of Robotic Bipolar Forceps for Brain Tumor Resection

Journal of Medical Devices ◽

10.1115/1.4051361 ◽

2021 ◽

Author(s):

Xiu-Heng Zhang ◽

Heng Zhang ◽

Zhen Li ◽

Gui-Bin Bian

Keyword(s):

Brain Tumor ◽

Real Time ◽

Force Measurement ◽

Measurement Techniques ◽

Tumor Resection ◽

Three Dimensional ◽

Contact Forces ◽

Surgical Instruments ◽

Force Perception ◽

Brain Tumor Resection

Abstract Three-dimensional force perception is critically important in the enhancement of human force perception to minimize brain injuries resulting from excessive forces applied by surgical instruments in robot-assisted brain tumor resection. And surgeons are not responsive enough to interpret tool-tissue interaction forces. In previous studies, various force measurement techniques have been published. In neurosurgical scenarios, there are still some drawbacks to these presented approaches to forces perception. Because of the narrow, and slim configuration of bipolar forceps, three-dimensional contact forces on forceps tips is not easy to be traced in real-time. Five fundamental acts of handling bipolar forceps are poking, opposing, pressing, opening, and closing. The first three acts independently correspond to the axial force of z, x, y. So, in this paper, typical interactions between bipolar forceps and brain tissues have been analyzed. A three-dimensional force perception technique to collect force data on bipolar forceps tips by installing three Fiber Bragg Grating Sensors (FBGs) on each prong of bipolar forceps in real-time is proposed. Experiments using a tele-neurosurgical robot were performed on an in-vitro pig brain. In the experiments, three-dimensional forces were tracked in real-time. It is possible to experience forces at a minimum of 0.01 N. The three-dimensional force perception range is 0-4 N. The calibrating resolution on x, y, and z, is 0.01, 0.03, 0.1 N, separately. According to our observation, the measurement accuracy precision is over 95%.

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Modern Geodetic Measurement Techniques in Gravimetric Studies on the Example of Gypsum Karst in the Siesławice Region

E3S Web of Conferences ◽

10.1051/e3sconf/20183503002 ◽

2018 ◽

Vol 35 ◽

pp. 03002 ◽

Cited By ~ 1

Author(s):

Sławomir Porzucek ◽

Monika Łój ◽

Karolina Matwij ◽

Wojciech Matwij

Keyword(s):

Laser Scanning ◽

Measurement Techniques ◽

Three Dimensional ◽

Digital Terrain Model ◽

Field Studies ◽

Surface Zone ◽

Three Dimensional Model ◽

Geodetic Measurement ◽

Near Surface ◽

Gypsum Karst

In the region of Siesławice (near Busko-Zdrój, Poland) there are unique phenomena of gypsum karst. Atmospheric factors caused numerous gypsum outcrops, canals and underground voids. The article presents the possibility of using non-invasive gravimetric surveys supplemented with geodetic measurements to illustrate karst changes occurring around the void. The use of modern geodetic measurement techniques including terrestrial and airborne laser scanning enables to generate a digital terrain model and a three-dimensional model of voids. Gravimetric field studies allowed to map the anomalies of the gravitational field of the near-surface zone. Geodetic measurement results have made it possible to accurately determine the terrain correction that supplemented the gravimetric anomaly information. Geophysical interpretation indicate the presence of weathered rocks in the near surface zone and fractures and loosened zones located surround the karst cave.

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Three-Dimensional Mirror Surface Measurement Based on Local Blur Analysis of Phase Measuring Deflectometry System

Traitement du signal ◽

10.18280/ts.370508 ◽

2020 ◽

Vol 37 (5) ◽

pp. 763-771

Author(s):

Hongyu Sun ◽

Le Wang ◽

Zhan Song ◽

Geng Chen

Keyword(s):

Measurement Techniques ◽

Three Dimensional ◽

Block Matching ◽

Surface Measurement ◽

Mirror Surface ◽

Reconstruction Accuracy ◽

Surface Reflection ◽

Block Matching Algorithm ◽

Reflective Mirror ◽

Spatially Varying

Despite the marked progress in recent years, structured light-based three-dimensional (3D) measurement techniques still have difficulty in capturing mirror surface reflection. The accuracy of 3D reconstruction for mirror objects should be further improved to adapt to the high reflectivity and curvature of such objects. To improve the stripe definition and reconstruction accuracy of highly reflective mirror objects, this paper analyzes the local blur of defocus stripes in phase measuring deflectometry (PMD) system, and presents a method to analyze the spatially varying defocusing and de-blurring, with the aid of a 3D block matching algorithm, thereby focusing on defocus stripes. Experimental results show that the proposed method can achieve micron-level reconstruction accuracy of standard flat mirrors, and detect the defects on highly reflective mirror objects at a high precision.

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Basic Study on High-density Ferroelectric Data Storage Using Scanning Nonlinear Dielectric Microscopy

MRS Proceedings ◽

10.1557/proc-748-u5.5 ◽

2002 ◽

Vol 748 ◽

Cited By ~ 1

Author(s):

Yoshiomi Hiranaga ◽

Kenjiro Fujimoto ◽

Yasuo Wagatsuma ◽

Yasuo Cho ◽

Atsushi Onoe ◽

...

Keyword(s):

Data Storage ◽

Scanning Probe Microscopy ◽

High Density ◽

Scanning Probe ◽

Ferroelectric Polarization ◽

Domain Formation ◽

Basic Study ◽

Polarization Distribution ◽

Nonlinear Dielectric ◽

Probe Microscopy

ABSTRACTScanning Nonlinear Dielectric Microscopy (SNDM) is the method for observing ferroelectric polarization distribution, and now, its resolution has become to the sub-nanometer order, which is much higher than other scanning probe microscopy (SPM) methods for the same purpose. Up to now, we have studied high-density ferroelectric data storage using this microscopy. In this study, we have conducted fundamental experiments of nano-sized inverted domain formation in LiTaO3 single, and successfully formed inverted dot array with the density of 1.5 Tbit/inch2.

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Dielectric Metrology VIA Microwave Tomography: Present and Future

MRS Proceedings ◽

10.1557/proc-347-259 ◽

1994 ◽

Vol 347 ◽

Cited By ~ 21

Author(s):

J.Ch. Bolomey ◽

N. Joachimowicz

Keyword(s):

Inverse Scattering ◽

A Priori ◽

Scattering Problem ◽

Measurement Techniques ◽

Three Dimensional ◽

Inverse Scattering Problem ◽

Dielectric Characterization ◽

Sample Shape ◽

Three Dimensional Configuration ◽

Characterization Of Materials

ABSTRACTUntil now, the measurement techniques used for the dielectric characterization of materials require severe limitations in terms of sample shape, size and homogeneity. This paper considers the dielectric permittivity measurement as a non-linear inverse scattering problem. Such an approach allows to identify the quantities to be measured and suggests possible experimental arrangements. The problem is shown to be significantly simplified if the shape of the material is known and if some a priori knowledge of the averaged value of the permittivity in the material under test is available. Two test cases have been selected to illustrate the state of the art in solving such inverse problems. The first one consists of a two-dimensional configuration which is applicable to cylindrical objects, and the second one to a vector three-dimensional configuration applicable, for instance, to cubic samples. The main limitations of such an inverse scattering approach are discussed and expected improvements in the near future are analysed.

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