Computer Simulation of Three-Dimensional Chip Kinematics in Machining

Manufacturing ◽  
2002 ◽  
Author(s):  
Ning Fang
Keyword(s):  
Mathematical Formulation ◽  
Three Dimensional ◽  
Research Area ◽  
Cnc Machining ◽  
Helical Axis ◽  
Flow Angle ◽  
On Chip ◽  
Cartesian Coordinate ◽  
Inclined Angle ◽  
Side Flow

Effective chip control is an essential requirement of modern automatic and computer numerically controlled (CNC) machining operations. This paper asserts that the study of chip control can be divided into three branches—chip dynamics, chip kinematics, and chip breaking mechanics—each having different research emphasis. Chip kinematics is becoming a promising research area, serving as an essential bridge between the other two branches. In developing the mathematical formulation of chip kinematics, this paper introduces three patterns of chip curl, i.e., up-, side-, and lateral-curl, followed by the establishment of a Cartesian coordinate system. Chip form is measured by three geometric parameters: the resultant radius R of chip curl, the pitch P of the chip helix, and the inclined angle θ of the helical axis to the helical surface. It is revealed that the final chip form is determined by four governing variables: chip up-, side-, and lateral-curl radii (Ru, Rs, and Rl) and chip side-flow angle (ηs). The effect of Ru, Rs, Rl, and ηs on chip forms is investigated. A set of new chip kinematical equations and computer-simulated chip forms are also established in this paper.

Kinematic Characterization of Chip Lateral-Curl—The Third Pattern of Chip Curl in Machining

2002 ◽  
Vol 124 (3) ◽  
pp. 667-675 ◽  
Author(s):  
Ning Fang
Keyword(s):  
Theoretical Analysis ◽  
Computer Simulations ◽  
Vector Analysis ◽  
Flow Angle ◽  
The Third ◽  
On Chip ◽  
Machining Operations ◽  
Side Flow

Two patterns of chip curl, namely up- and side-curl, have been widely recognized in machining operations. This paper presents the third pattern of chip curl that is called lateral-curl. The rotating axis of chip lateral-curl is perpendicular to the rotating axes of up- and side-curl. The essential differences are illustrated between the chip lateral-curl concept and the “chip-twisting” concept presented in other related studies. Based on an analytical vector analysis, a new kinematic characterization is presented for the natural (or born) lateral-curl of the chip that is associated with flat-faced tool machining. It is demonstrated that chip forms (or shapes) can be determined by four governing variables: the chip up-, lateral-, and side-curl radii and the chip side-flow angle. A method to indirectly measure the chip lateral-curl radius is presented. The effect of chip lateral-curl on chip forms is investigated through cutting tests, theoretical analysis, and computer simulations.

A THREE-DIMENSIONAL GEOLOGIC CONCEPTUAL MODEL BENEATH THE IDAHO NATIONAL LAB’S GEOTHERMAL RESOURCE RESEARCH AREA

2016 ◽  
Author(s):  
James T. St. Clair ◽  
◽  
Michael Janis ◽  
Robert K. Podgorney ◽  
Michael McCurry ◽  
...  
Keyword(s):  
Conceptual Model ◽  
Three Dimensional ◽  
Research Area ◽  
Geothermal Resource ◽  
Resource Research

scholarly journals Electromechanically reconfigurable optical nano-kirigami

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Shanshan Chen ◽  
Zhiguang Liu ◽  
Huifeng Du ◽  
Chengchun Tang ◽  
Chang-Yin Ji ◽  
...  
Keyword(s):  
Near Infrared ◽  
Large Range ◽  
Three Dimensional ◽  
High Contrast ◽  
Si Substrate ◽  
High Modulation ◽  
Gold Nanostructure ◽  
Infrared Wavelengths ◽  
On Chip ◽  
Nano Electromechanical System

AbstractKirigami, with facile and automated fashion of three-dimensional (3D) transformations, offers an unconventional approach for realizing cutting-edge optical nano-electromechanical systems. Here, we demonstrate an on-chip and electromechanically reconfigurable nano-kirigami with optical functionalities. The nano-electromechanical system is built on an Au/SiO2/Si substrate and operated via attractive electrostatic forces between the top gold nanostructure and bottom silicon substrate. Large-range nano-kirigami like 3D deformations are clearly observed and reversibly engineered, with scalable pitch size down to 0.975 μm. Broadband nonresonant and narrowband resonant optical reconfigurations are achieved at visible and near-infrared wavelengths, respectively, with a high modulation contrast up to 494%. On-chip modulation of optical helicity is further demonstrated in submicron nano-kirigami at near-infrared wavelengths. Such small-size and high-contrast reconfigurable optical nano-kirigami provides advanced methodologies and platforms for versatile on-chip manipulation of light at nanoscale.

scholarly journals Brain capillary structures of schizophrenia cases and controls show a correlation with their neuron structures

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Rino Saiga ◽  
Masayuki Uesugi ◽  
Akihisa Takeuchi ◽  
Kentaro Uesugi ◽  
Yoshio Suzuki ◽  
...  
Keyword(s):  
Blood Vessels ◽  
Structural Parameters ◽  
Three Dimensional ◽  
Superior Temporal Gyrus ◽  
Anterior Cingulate ◽  
Dimensional Structure ◽  
Constant Diameter ◽  
The Mean ◽  
Cartesian Coordinate ◽  
Micrometer Scale

AbstractBrain blood vessels constitute a micrometer-scale vascular network responsible for supply of oxygen and nutrition. In this study, we analyzed cerebral tissues of the anterior cingulate cortex and superior temporal gyrus of schizophrenia cases and age/gender-matched controls by using synchrotron radiation microtomography or micro-CT in order to examine the three-dimensional structure of cerebral vessels. Over 1 m of cerebral blood vessels was traced to build Cartesian-coordinate models, which were then used for calculating structural parameters including the diameter and curvature of the vessels. The distribution of vessel outer diameters showed a peak at 7–9 μm, corresponding to the diameter of the capillaries. Mean curvatures of the capillary vessels showed a significant correlation to the mean curvatures of neurites, while the mean capillary diameter was almost constant, independent of the cases. Our previous studies indicated that the neurites of schizophrenia cases are thin and tortuous compared to controls. The curved capillaries with a constant diameter should occupy a nearly constant volume, while neurons suffering from neurite thinning should have reduced volumes, resulting in a volumetric imbalance between the neurons and the vessels. We suggest that the observed structural correlation between neurons and blood vessels is related to neurovascular abnormalities in schizophrenia.

scholarly journals An Overview on the Rheology, Mechanical Properties, Durability, 3D Printing, and Microstructural Performance of Nanomaterials in Cementitious Composites

Materials ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 2950
Author(s):  
Hongwei Song ◽  
Xinle Li
Keyword(s):  
Mechanical Properties ◽  
3D Printing ◽  
Three Dimensional ◽  
Cementitious Materials ◽  
Research Area ◽  
Cementitious Composites ◽  
Split Tensile Strength ◽  
Contour Crafting ◽  
Wide Range ◽  
Active Research

The most active research area is nanotechnology in cementitious composites, which has a wide range of applications and has achieved popularity over the last three decades. Nanoparticles (NPs) have emerged as possible materials to be used in the field of civil engineering. Previous research has concentrated on evaluating the effect of different NPs in cementitious materials to alter material characteristics. In order to provide a broad understanding of how nanomaterials (NMs) can be used, this paper critically evaluates previous research on the influence of rheology, mechanical properties, durability, 3D printing, and microstructural performance on cementitious materials. The flow properties of fresh cementitious composites can be measured using rheology and slump. Mechanical properties such as compressive, flexural, and split tensile strength reveal hardened properties. The necessary tests for determining a NM’s durability in concrete are shrinkage, pore structure and porosity, and permeability. The advent of modern 3D printing technologies is suitable for structural printing, such as contour crafting and binder jetting. Three-dimensional (3D) printing has opened up new avenues for the building and construction industry to become more digital. Regardless of the material science, a range of problems must be tackled, including developing smart cementitious composites suitable for 3D structural printing. According to the scanning electron microscopy results, the addition of NMs to cementitious materials results in a denser and improved microstructure with more hydration products. This paper provides valuable information and details about the rheology, mechanical properties, durability, 3D printing, and microstructural performance of cementitious materials with NMs and encourages further research.

scholarly journals High-Performance On-Chip Silicon Beamsplitter Based on Subwavelength Metamaterials for Enhanced Fabrication Tolerance

Nanomaterials ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 1304
Author(s):  
Raquel Fernández de Cabo ◽  
David González-Andrade ◽  
Pavel Cheben ◽  
Aitor V. Velasco
Keyword(s):  
Integrated Circuits ◽  
Fundamental Mode ◽  
High Performance ◽  
Three Dimensional ◽  
High Sensitivity ◽  
Power Splitting ◽  
Excess Loss ◽  
Power Splitters ◽  
On Chip ◽  
Efficient Power

Efficient power splitting is a fundamental functionality in silicon photonic integrated circuits, but state-of-the-art power-division architectures are hampered by limited operational bandwidth, high sensitivity to fabrication errors or large footprints. In particular, traditional Y-junction power splitters suffer from fundamental mode losses due to limited fabrication resolution near the junction tip. In order to circumvent this limitation, we propose a new type of high-performance Y-junction power splitter that incorporates subwavelength metamaterials. Full three-dimensional simulations show a fundamental mode excess loss below 0.1 dB in an ultra-broad bandwidth of 300 nm (1400–1700 nm) when optimized for a fabrication resolution of 50 nm, and under 0.3 dB in a 350 nm extended bandwidth (1350–1700 nm) for a 100 nm resolution. Moreover, analysis of fabrication tolerances shows robust operation for the fundamental mode to etching errors up to ± 20 nm. A proof-of-concept device provides an initial validation of its operation principle, showing experimental excess losses lower than 0.2 dB in a 195 nm bandwidth for the best-case resolution scenario (i.e., 50 nm).

A new efficient multi‐task applications mapping for three‐dimensional Network‐on‐Chip based MPSoC

2021 ◽  
Author(s):  
Khadidja Gaffour ◽  
Mohammed Kamel Benhaoua ◽  
Abou El Hassan Benyamina ◽  
Amit Kumar Singh
Keyword(s):  
Three Dimensional ◽  
Network On Chip ◽  
Dimensional Network ◽  
On Chip

On the Flexural-Torsional Behavior of a Straight Elastic Beam Subject to Terminal Moments

1993 ◽  
Vol 60 (2) ◽  
pp. 498-505 ◽  
Author(s):  
Z. Tan ◽  
J. A. Witz
Keyword(s):  
Coordinate System ◽  
Cross Section ◽  
Equilibrium Equation ◽  
Three Dimensional ◽  
Circular Cross Section ◽  
Elastic Beam ◽  
Cartesian Coordinate System ◽  
Kinematic Constraints ◽  
Torsional Behavior ◽  
Cartesian Coordinate

This paper discusses the large-displacement flexural-torsional behavior of a straight elastic beam with uniform circular cross-section subject to arbitrary terminal bending and twisting moments. The beam is assumed to be free from any kinematic constraints at both ends. The equilibrium equation is solved analytically with the full expression for curvature to obtain the deformed configuration in a three-dimensional Cartesian coordinate system. The results show the influence of the terminal moments on the beam’s deflected configuration.

The Use of Photogrammetry in Piping Design

1983 ◽  
Vol 197 (2) ◽  
pp. 125-138 ◽  
Author(s):  
P A Bracewell ◽  
U R Klement
Keyword(s):  
Information Retrieval ◽  
Mathematical Formulation ◽  
Three Dimensional ◽  
Cost Effective ◽  
Process Industry ◽  
Process Plant ◽  
Definition Of ◽  
High Degree ◽  
Positional Data

Piping design for ‘revamp’ projects in the process industry requires the retrieval of large amounts of ‘as-built’ data from existing process plant installations. Positional data with a high degree of accuracy are required. Photogrammetry, the science of measurement from photographs, was identified in Imperial Chemical Industries plc (ICI) as a suitable tool for information retrieval. The mathematical formulation enabling the definition of three-dimensional positions from photographic information is described. The process of using ICI's photogrammetric system for the definition of complete objects such as structures and pipes is illustrated. The need for specialized photogrammetric software for design purposes is explained. A case study describing how the photogrammetric system has been applied is described and graphical outputs from this exercise are shown. It is concluded that this particular photogrammetric system has proved to be a cost effective and accurate tool for the retrieval of ‘as-built’ information.

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