scholarly journals Reconfigurable Trusses of Nonlinear Morphing Elements

2018 ◽  
Author(s):  
Chrysoula Aza ◽  
Alberto Pirrera ◽  
Mark Schenk
Keyword(s):  
Double Helix ◽  
Nonlinear Stiffness ◽  
Helical Pitch ◽  
Reconfigurable Mechanisms ◽  
Wide Range ◽  
Stiffness Characteristics ◽  
Constituent Elements

Reconfigurable mechanisms are capable of changing their behavior during operation and perform different tasks through changes of their configuration. A compliant, multistable, reconfigurable mechanism is introduced which consists of nonlinear morphing elements assembled in a truss-like configuration. These constituent elements are made of composite strips assembled to form a double-helix and exhibit tailorable nonlinear stiffness characteristics, including bistability. The mechanism’s behavior can be tailored by tuning the inherent properties of the helical components, leading to a wide range of responses. This work explores the reconfigurability of the mechanism, based on the ability to change the helical pitch and the resulting stiffness.

Nonlinear stiffness characteristics of the annular ligament

2014 ◽  
Vol 136 (4) ◽  
pp. 1756-1767 ◽  
Author(s):  
M. Lauxmann ◽  
A. Eiber ◽  
F. Haag ◽  
S. Ihrle
Keyword(s):  
Annular Ligament ◽  
Nonlinear Stiffness ◽  
Stiffness Characteristics

scholarly journals Design of the designershoes with the use of innovative technologies

2020 ◽  
Vol 80 (4) ◽  
pp. 115-121
Author(s):  
J. Mazina ◽  
◽  
L. Shokorova ◽  
I. Chechevatkin ◽  
Keyword(s):  
Experimental Models ◽  
Age Group ◽  
Technical Data ◽  
Innovative Technologies ◽  
Wide Range ◽  
Rational Understanding ◽  
Functional Features ◽  
Smart Things ◽  
Constituent Elements ◽  
Further Development

The article discusses methods for creating smart things, using the example of the use of innovative technologies in the field of materials for clothing and footwear. The factors of form formation are substantiated by the example of the preferences of an individual customer who forms its image through accessories and shoes. The author considers the factors of shaping, based on the special functional features of shoes in connection with ergonomic factors. The designer is able to foresee the factor of transformability in modern footwear, changes in functional qualities, appearance, and design features of new footwear. As a result, on the basis of these transformations, to get a new emotional image and a new form. The shape of the shoe becomes a factor for transformations at the request of the customer. The article discusses the functional tasks of this shoe, plastic characteristics, technical and design tasks. As research methods, the article proposes variants of experimental models with possible stages of transformation, presents preliminary technical data, conducts a comparative analysis with innovative footwear samples of famous world designers, and makes assumptions about the development of this model in the future. An experimental method was used during the study. A shoe shape was developed, which took into account the preferences of the age group of 12-16 years old, relying on this category of consumers, we were able to go beyond the rational understanding of shoes as a functional form and gave it the meaning of a fantastic image, which allowed us to consider the form in the semantic and artistic context dictated by this age group of consumers. In addition, investing in this model the concept of "smart shoes", we considered not only the ability of modification and transformation by rearranging replaceable parts, the possibility of designing and reincarnating from one form to another, combining the constituent elements of the shoe into one whole, but also the development of the creative potential of the consumer, who at its own discretion can rebuild the structure and, in fact, as a designer itself, form a new model. The article makes assumptions about its further development in various fields of activity. For example, medicine, sports, art, etc. Considering the introduction of new materials, we relied on discoveries in the field of nanotechnology and considered among the possible features of this model the change in color on the basis, the reaction of materials to light, temperature, etc. The project is aimed at creating such shoes that will be developed for a wide range of consumers thanks to the wide range of possibilities contained in the design of the form and the features of modern materials.

scholarly journals Reading M87's DNA: A Double Helix Revealing a Large-scale Helical Magnetic Field

2021 ◽  
Vol 923 (1) ◽  
pp. L5
Author(s):  
Alice Pasetto ◽  
Carlos Carrasco-González ◽  
José L. Gómez ◽  
José-Maria Martí ◽  
Manel Perucho ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Large Scale ◽  
Double Helix ◽  
High Sensitivity ◽  
Polarization Degree ◽  
Very Large Array ◽  
Wide Range ◽  
Helical Magnetic Field ◽  
Helical Configuration ◽  
The Magnetic Field

Abstract We present unprecedented high-fidelity radio images of the M87 jet. We analyzed Jansky Very Large Array broadband full-polarization radio data from 4 to 18 GHz. The observations were taken with the most extended configuration (A configuration), which allows the study of the emission of the jet up to kiloparsec scales with a linear resolution of ∼10 pc. The high sensitivity and resolution of our data allow us to resolve the jet width. We confirm a double-helix morphology of the jet material between ∼300 pc and ∼1 kpc. We found a gradient of the polarization degree with a minimum at the projected axis and maxima at the jet edges and a gradient in the Faraday depth with opposite signs at the jet edges. We also found that the behavior of the polarization properties along the wide range of frequencies is consistent with internal Faraday depolarization. All of these characteristics strongly support the presence of a helical magnetic field in the M87 jet up to 1 kpc from the central black hole, although the jet is most likely particle-dominated at these large scales. Therefore, we propose a plausible scenario in which the helical configuration of the magnetic field has been maintained to large scales thanks to the presence of Kelvin–Helmholtz instabilities.

Nonlinear Response of a Dynamic System due to Oscillatory Flow

1987 ◽  
Vol 109 (4) ◽  
pp. 345-356 ◽  
Author(s):  
Y. M. Huang ◽  
C. M. Krousgrill ◽  
A. K. Bajaj
Keyword(s):  
Harmonic Balance ◽  
Nonlinear Response ◽  
Oscillatory Flow ◽  
Nonlinear Stiffness ◽  
Method Of Averaging ◽  
Secondary Resonances ◽  
Incremental Harmonic Balance ◽  
Nonzero Mean ◽  
Stiffness Characteristics ◽  
Solution Formulation

The dynamic response of a structure exhibiting nonlinear stiffness characteristics and excited by a nonzero mean oscillatory fluid flow is investigated. Both the method of averaging and a multi-frequency incremental harmonic balance approach are used in understanding the primary and secondary resonances in the response. Several parameter studies are presented where the results of these two methods are compared with those obtained by numerical integration and are discussed in detail. The results point to the need for a multi-frequency solution formulation for accurate representation of the response offset and to the difficulties of using the standard method of averaging formulation for investigation of secondary resonances in the response of this system.

scholarly journals Predicting Nonlinear Stiffness, Motion Range, and Load-Bearing Capability of Leaf-Type Isosceles-Trapezoidal Flexural Pivot Using Comprehensive Elliptic Integral Solution

2020 ◽  
Vol 2020 ◽  
pp. 1-11
Author(s):  
Aimei Zhang ◽  
Yanjie Gou ◽  
Xihui Yang
Keyword(s):  
Elliptic Integral ◽  
Integral Solution ◽  
Leaf Spring ◽  
Nonlinear Stiffness ◽  
Load Bearing ◽  
Large Rotation ◽  
Leaf Type ◽  
Proposed Model ◽  
Motion Range ◽  
Stiffness Characteristics

A leaf-type isosceles-trapezoidal flexural (LITF) pivot consists of two leaf springs that are situated in the same plane and intersect at a virtual center of motion outside the pivot. The LITF pivot offers many advantages, including large rotation range and monolithic structure. Each leaf spring of a LITF pivot subject to end loads is deflected into an S-shaped configuration carrying one or two inflection points, which is quite difficult to model. The kinetostatic characteristics of the LITF pivot are precisely modeled using the comprehensive elliptic integral solution for the large-deflection problem derived in our previous work, and the strength-checking method is further presented. Two cases are employed to verify the accuracy of the model. The deflected shapes and nonlinear stiffness characteristics within the range of the yield strength are discussed. The load-bearing capability and motion range of the pivot are proposed. The nonlinear finite element results validate the effectiveness and accuracy of the proposed model for LITF pivots.

First Integration Steps of Cu-based DNA Nanowires for interconnections

2016 ◽  
Vol 2016 (DPC) ◽  
pp. 000650-000679 ◽  
Author(s):  
Christophe Brun ◽  
Corentin Carmignani ◽  
Cheikh Tidiane-Diagne ◽  
Simona Torrengo ◽  
Pierre-Henri Elchinger ◽  
...  
Keyword(s):  
Silicon Oxide ◽  
Double Helix ◽  
Electrical Characterization ◽  
Good Control ◽  
Electrical Performance ◽  
Oxide Surface ◽  
Copper Nanowires ◽  
Wide Range ◽  
Lift Off ◽  
Metallization Process

In the wide range of emergent nanotechnologies, DNA-based microelectronics has shown an important potential for components miniaturization and auto-assembling approaches applicable to future silicon-based electronic circuits [1]. In order to pursue the Moore's law, interconnections must be indeed addressed at the nanoscale, with a good control of their size, location and electrical & thermal performances. With its natural auto-assembling property, its 2-nm-double-helix diameter and its several metallization possibilities, DNA is a promising candidate to build bio-inspired electronic components [1]. DNA has been first metallized by Erez Braun in 1998 using a silver electroless method [2]. Since 1998, several groups have worked on DNA metallization using different chemistries with metals such as Pd, Pt, Au, Ag and Cu [3]. Most of these works have presented electrical and morphological characterizations of few metallic nanowires. However, in order to initiate DNA-based-nanowires integration on silicon technologies, we must start to implement nanowires on silicon at wafer scale. We have thus developed a platform based on silicon technologies providing morphological and electrical characterizations of copper nanowires built from DNA [4]. This platform will allow us to simultaneously characterize a large number of nanowires, returning a statistic of their electrical performance, and thus allowing the optimization of the copper nanowire metallization process. Two main approaches are proposed to fabricate and contact a large number of copper nanowires with metallic electrodes in order to study their electrical behavior. In both approaches, a linear 16-μm-length DNA phage is used. The first approach consists in aligning DNA wires on a hydrophobic silicon oxide surface by a method called DNA combing. On a second time, aligned DNA wires are all metallized by electroless process [4]. 5-nm-diameter copper nanowires have been so far achieved by this method and focus on improving the metallization process is currently at stake. Finally, Ti/Au electrodes are fabricated on the nanowires by a classical lift-off process in order to electrically connect them. The advantage of this approach is the very accurate nanowires alignment and their homogeneity over the surface. However, the low number of aligned nanowires per surface unit (10–20μm−2) and the high electrical resistance of each (>kohms) makes the electrical characterization quite complex. On the other side, the second approach consists in fabricating the Ti/Au electrodes first and then aligning or randomly depositing the copper nanowires at their surface. Same protocols are used to align and metallize the DNA nanowires for both approaches. The advantage of this second approach is a higher nanowire density deposited on the electrodes. However, a higher contact resistance and a lower control of nanowires alignment are obtained. Both approaches are currently explored and permit to explore a wide range of parameters for copper nanowires metallization process improvement.

Effect of Negative Stiffness Content on the Periodic Motion of Nonlinearly Coupled Oscillators

2021 ◽  
Vol 16 (11) ◽  
Author(s):  
Mohammad A. Al-Shudeifat
Keyword(s):  
Coupled Oscillators ◽  
Dynamical Behavior ◽  
Negative Stiffness ◽  
Nonlinear Frequency ◽  
Nonlinear Stiffness ◽  
Nonlinear Coupling ◽  
Nonlinear Dynamical ◽  
Wide Range ◽  
Coupling Force ◽  
Linear And Nonlinear

Abstract The linear and nonlinear stiffness coupling forces in dynamical oscillators are usually dominated by positive stiffness components. Therefore, plotting the resultant force in y-axis with respect to the change in displacement in x-axis results in an odd symmetry in the first and third quadrants of the xy-plane. However, the appearance of negative stiffness content in coupling elements between dynamical oscillators generates a force that can be dominated by an odd symmetry in the second and fourth quadrants. The underlying nonlinear dynamical behavior of systems employing this kind of force has not been well-studied in the literature. Accordingly, the considered system here is composed of two linear oscillators that are nonlinearly coupled by a force of which the negative stiffness content is dominant. Therefore, the underlying dynamical behavior of the considered system in physical and dimensionless forms is studied on the frequency-energy plots where many backbone curves of periodic solution have been obtained. It is found that within a wide range of nonlinear frequency levels, the nonlinear coupling force is dominated by a strong negative stiffness content at the obtained frequency-energy plots backbones.

Electrooptic Materials Requirements for Optical Information Processing and Computing

1991 ◽  
Vol 228 ◽  
Author(s):  
Praveen Asthana ◽  
Edward Herbulock ◽  
Zaheed Karim ◽  
Chris Kyriakakis ◽  
Gregory P. Nordin ◽  
...  
Keyword(s):  
Information Processing ◽  
Optical Information ◽  
Computing Systems ◽  
Optical Information Processing ◽  
Wide Range ◽  
Critical Issues ◽  
Photorefractive Materials ◽  
Holographic Interconnections ◽  
Constituent Elements ◽  
Important Constituent

ABSTRACTPhotorefractive materials comprise an important category of electrooptic materials, and are important constituent elements in a wide range of devices designed specifically for use in optical information processing and computing systems. Critical issues affecting the development and applicability of photorefractive materials are examined from the perspective of photonic neural network implementations that incorporate photorefractive volume holographic interconnections.

Sign in / Sign up

Export Citation Format

Share Document