A Mechanical Hand-Like Functional Surface Capable of Efficiently Grasping and Non-Destructively Releasing Droplets

The technological (deposition rate, coating composition) and functional (surface roughness, microhardness) characteristics of chemical composite coatings Ni—Cu—P—Cr2O3 obtained from weakly acidic and slightly alkaline solutions are compared. It is shown that coatings deposited from slightly alkaline solution contain slightly less phosphorus and chromium oxide than coatings deposited from weakly acid solution (2...3 % wt. phosphorus and up to 3.4 % wt. chromium oxide), formed at higher rate (24...25 microns per 1 hour of deposition at temperature of 80 °C), are characte rized by lower roughness and increased microhardness. The Vickers microhardness at 0.05 N load of composite coatings obtained from slightly alkaline solution and heat-treated at 400 °C for 1 hour is 13.5...15.2 GPa, which is higher than values for coatings deposited made of weakly acidic solution. The maximum microhardness of coatings is achieved at concentration 20 g/l of Cr2O3 particles. The technology of chemical deposition of Ni—Cu—P—Cr2O3 coatings formed in slightly alkaline solution is promising for obtaining of materials with increased hardness and wear resistance.

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Stoichiometric composition of thin-film surface structures and its influence on the functional characteristics as regards gyroscopic devices

Voprosy Materialovedeniya ◽

10.22349/1994-6716-2019-100-4-78-90 ◽

2020 ◽

pp. 78-90

Author(s):

M. A. Tit ◽

S. N. Belyaev

Keyword(s):

Thin Film ◽

Titanium Nitride ◽

Niobium Carbide ◽

Structural Phase ◽

Stoichiometric Composition ◽

Film Surface ◽

Surface Structures ◽

Functional Surface ◽

Base Surface ◽

Thin Film Surface

This article considers the research results of the effect of stoichiometry on the properties of titanium nitride thin-film coatings of the float and electrostatic gyroscopes. It presents the results of tests of such mechanical and optical characteristics of titanium nitride thin-film structures as microhardness, resistance to wear and friction, and image contrast determined by the reflection coefficients of a titanium nitride base surface and a raster pattern formed by local laser oxidation. When making a rotor of a cryogenic gyroscope, the prospects of use and technological methods for the formation of functional surface structures of niobium carbide and nitride are considered. It is shown that during the formation of coatings of the required composition, the most important is the thermodynamic estimation of possible interactions. These interactions allow us to accomplish the structural-phase modification of the material, which is determined by the complex of possible topochemical reactions leading to the formation of compounds, including non-stoichiometric composition.

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A simplified model of a multi-jointed mechanical finger calibrated with experimental data by vision system

Proceedings of the Institution of Mechanical Engineers Part K Journal of Multi-body Dynamics ◽

10.1177/1464419320955115 ◽

2021 ◽

Vol 235 (1) ◽

pp. 164-175

Author(s):

C Cosenza ◽

V Niola ◽

S Savino

Keyword(s):

Experimental Data ◽

Vision System ◽

Control Strategies ◽

Image Correlation ◽

Robotic Hand ◽

Prosthetic Device ◽

Prosthetic Hands ◽

Mechanical Hand ◽

Free Mode ◽

Mechanical Finger

The development of suitable models for mechanical fingers, whether they are part of prosthetic device or of a robotic hand, is a powerful tool to predict the behaviour of their components since the early stages of design, especially for underactuated mechanisms. Experimental data can improve the reliability of such models and promote their application to build proper control strategies especially for prosthetic hands. Here, we have developed a multi-jointed model of a mechanical finger. The finger is part of the Federica hand: an underactuated mechanical hand that was conceived for prosthetic purpose. The model accounts for friction phenomena in the finger and it is tuned with experimental data acquired through a digital image correlation device. The model allowed us to write kinematics relations of the phalanges and evaluate finger configurations in relation to the closure velocity. Moreover, it was possible to estimate the tendon force and the work analysis occurring during the closure tasks, both in free mode and in presence of objects.

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Functional surface microstructures inspired by nature – From adhesion and wetting principles to sustainable new devices

Progress in Materials Science ◽

10.1016/j.pmatsci.2021.100823 ◽

2021 ◽

pp. 100823

Author(s):

Eduard Arzt ◽

Haocheng Quan ◽

Robert M. McMeeking ◽

René Hensel

Keyword(s):

Functional Surface ◽

Surface Microstructures ◽

New Devices

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Antireflective and Superhydrophilic Structure on Graphite Written by Femtosecond Laser

Micromachines ◽

10.3390/mi12030236 ◽

2021 ◽

Vol 12 (3) ◽

pp. 236

Author(s):

Rui Lou ◽

Guangying Li ◽

Xu Wang ◽

Wenfu Zhang ◽

Yishan Wang ◽

...

Keyword(s):

Femtosecond Laser ◽

Near Infrared ◽

High Efficiency ◽

Electronic Devices ◽

Sample Surface ◽

Graphite Surface ◽

Hazardous Substances ◽

Functional Surface ◽

Nano Structures ◽

Average Reflectance

Antireflection and superhydrophilicity performance are desirable for improving the properties of electronic devices. Here, we experimentally provide a strategy of femtosecond laser preparation to create micro-nanostructures on the graphite surface in an air environment. The modified graphite surface is covered with abundant micro-nano structures, and its average reflectance is measured to be 2.7% in the ultraviolet, visible and near-infrared regions (250 to 2250 nm). The wettability transformation of the surface from hydrophilicity to superhydrophilicity is realized. Besides, graphene oxide (GO) and graphene are proved to be formed on the sample surface. This micro-nanostructuring method, which demonstrates features of high efficiency, high controllability, and hazardous substances zero discharge, exhibits the application for functional surface.

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A general process for in situ formation of functional surface layers on ceramics

Nature ◽

10.1038/416064a ◽

2002 ◽

Vol 416 (6876) ◽

pp. 64-67 ◽

Cited By ~ 100

Author(s):

Toshihiro Ishikawa ◽

Hiroyuki Yamaoka ◽

Yoshikatsu Harada ◽

Teruaki Fujii ◽

Toshio Nagasawa

Keyword(s):

Functional Surface ◽

Surface Layers ◽

General Process ◽

In Situ Formation

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Homozygous Cys89Tyr CD59 deficiency allows non-functional surface localization of CD59

Immunobiology ◽

10.1016/j.imbio.2016.06.222 ◽

2016 ◽

Vol 221 (10) ◽

pp. 1224

Author(s):

Netanel Karbian ◽

Yael Eshed-Eisenbach ◽

Ori Peles ◽

Dror Mevorach

Keyword(s):

Functional Surface ◽

Surface Localization

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Investigation of Binding Modes and Functional Surface of Scorpion Toxins ANEP to Sodium Channels 1.7

Toxins ◽

10.3390/toxins9120387 ◽

2017 ◽

Vol 9 (12) ◽

pp. 387 ◽

Cited By ~ 3

Author(s):

Yongbo Song ◽

Zeyu Liu ◽

Qi Zhang ◽

Chunming Li ◽

Wei Jin ◽

...

Keyword(s):

Sodium Channels ◽

Binding Modes ◽

Scorpion Toxins ◽

Functional Surface

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Unitary Micro-Patterning Structure-Induced Hydrophobic Silicon Surface

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.239-242.2524 ◽

2011 ◽

Vol 239-242 ◽

pp. 2524-2527

Author(s):

Si Si Liu ◽

Chao Hui Zhang ◽

Han Bing Zhang

Keyword(s):

Inductively Coupled Plasma ◽

Silicon Surface ◽

Scale Effects ◽

Silicon Surfaces ◽

Functional Surface ◽

Inductively Coupled ◽

Cassie State ◽

Micro Patterning ◽

Pillar Arrays ◽

The Relationship

The relationship between the wettability and the roughness structure on silicon surface is studied. The unitary microscale square pillar arrays are fabricated by the way of inductively coupled plasma (ICP). The wettability of water droplets on the silicon surface is changed from hydrophilic to hydrophobic only by introducing microscale pillarlike structure. Furthermore, the scale effects of the unitary rough structure on hydrophobicity are investigated. For those silicon surfaces with a fixed pillar height, the relatively larger scale of grooves leads the droplets wettability state to unstable Cassie state and the contact angle will initially get larger and then decrease with the increase of groove width. The research could provide further insights into the design of functional surface with controllable roughness-induced hydrophobic.

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