Gli autori desiderano ringraziare Ryan Tung per la sua assistenza e discussioni tecniche utili. Gli autori desiderano inoltre ringraziare l&#39;assistenza e il supporto dello staff tecnico Birck Nanotechnology Center. Questo lavoro è stato sostenuto dalla Defense Advanced Research Projects Agency sotto la Purdue Microonde riconfigurabile Evanescent-Mode cavità Filtri di studio. E anche da NNSA Centro di Pronostico affidabilità, integrità e capacità di sopravvivenza dei microsistemi e Dipartimento di Energia sotto Award Numero DE-FC5208NA28617. Le opinioni, pareri, e / o risultanze contenute in questo documento / presentazione sono quelle degli autori / presentatori e non devono essere interpretate come rappresentare le opinioni politiche o ufficiali, sia espressa o implicita, della Defense Advanced Research Projects Agency o il Dipartimento della Difesa.

<ol>
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Gli autori non hanno nulla da rivelare.

Bassa tensione residua Au deposizione di film e un rilascio secco con XeF 2 sono componenti criticamente nella fabbricazione di successo del dispositivo. Attuatori frangente campo elettrostatico forniscono forze relativamente basse rispetto al parallelo-piastra attuatori di campo. MEMS tipici sottili sollecitazioni a film di&gt; 60 MPa si tradurrà in tensioni elevate dell&#39;azionamento che può potenzialmente compromettere l&#39;affidabilità del EFFA MEMS. Per questo motivo la ricetta galvanica è accurat...

Sistemi microelettromeccanici (MEMS) utilizzano diversi meccanismi di attuazione per raggiungere spostamento meccanico. Le più popolari sono termale, piezoelettrico, magnetostatico, ed elettrostatiche. Per tempo di commutazione brevi, attuazione elettrostatica è la tecnica più popolare 1, 2. In pratica, i disegni meccanici critica smorzati offrono il miglior compromesso tra tempo di salita iniziale e tempo di assestamento. Dopo l&#39;applicazione della polarizzazione CC e azionare la membrana verso l&#39;elettrodo di pull-down, il tempo di assestamento non è un problema significativo in quanto la membrana si scatto verso il basso e rispettare l&#39;elettrodo di attuazione rivestito dielettrica. Diverse applicazioni hanno beneficiato del suddetto disegno di attuazione elettrostatica 3 - 8. Tuttavia, la presenza del elettrodo rivestito tendina dielettrico rende l&#39;attuatore suscettibile di ricarica dielettrico e attrito statico. Le membrane MEMS possono utilizzare un uprogettazione meccanica nderdamped per ottenere un veloce tempo di salita iniziale. Un esempio di progettazione meccanica sottosmorzato è il frangente campo elettrostatico azionato (EFFA) MEMS. Questa topologia ha esposto molto meno vulnerabilità di meccanismi di rottura tipici che affliggono i disegni elettrostatici basati 9-20. L&#39;assenza del controelettrodo parallelo e di conseguenza il campo elettrico parallelo e perciò questi MEMS sono naturalmente chiamati &quot;frangente campo&quot; azionato (Figura 1). Per la progettazione EFFA, l&#39;elettrodo di pull-down è suddiviso in due elettrodi separati che sono posizionati lateralmente compensate alla membrana in movimento, eliminando completamente la sovrapposizione tra le parti mobili e fisse del dispositivo. Tuttavia, la rimozione del substrato da sotto la membrana mobile riduce significativamente il film compressione smorzamento componente aumentando così il tempo di assestamento. Figura 2B è un esempio del tempo di assestamento in risposta a standard polarizzazione passo. Transitoria, o DC-dinamica applicate polarizzazione in tempo reale può essere usato per migliorare il tempo di assestamento 20-26. Figure 2C e 2D qualitativamente illustrano come una forma d&#39;onda variabile nel tempo può annullare efficacemente la suoneria. Attività di ricerca precedenti utilizzano metodi numerici per calcolare la tensione precisa e tempi di polarizzazione in ingresso per migliorare il tempo di commutazione. Il metodo in questo lavoro utilizza compatte espressioni in forma chiusa per il calcolo dei parametri della forma d&#39;onda di polarizzazione in ingresso. Inoltre, il lavoro precedente focalizzata sulla piastra di azionamento parallelo. Mentre le strutture sono progettate per essere sottosmorzato, squeeze-film di smorzamento è ancora disponibile in questa configurazione. Il metodo di attuazione presentata in questo lavoro è frangente campo di attuazione. In questa configurazione squeeze-film di smorzamento viene effettivamente eliminato. Questo rappresenta un caso estremo in cui lo smorzamento meccanico della trave MEMS è molto bassa. Questo documento descrive come fabbricare il dev EFFA MEMSgelati ed eseguire la misura per convalidare sperimentalmente il concetto di forma d&#39;onda.

<table border="0" cellpadding="0" cellspacing="0" width="746">
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:251px;">Chemical</td>
			<td style="width:163px;">Company</td>
			<td style="width:137px;">Catalogue number</td>
			<td style="width:195px;">Comments (optional)</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Buffered oxide etchant</td>
			<td>Mallinckrodt Baker</td>
			<td>1178</td>
			<td>Silicon dioxide etch, Ti etch</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Acetone</td>
			<td>Mallinckrodt Baker</td>
			<td>5356</td>
			<td>wafer clean</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Isopropyl alcohol</td>
			<td>Honeywell</td>
			<td>BDH-140</td>
			<td>wafer clean</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Hexamethyldisilizane</td>
			<td>Mallinckrodt Baker</td>
			<td>5797</td>
			<td>adhesion promoter</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Microposit SC 1827 Positive Photoresist</td>
			<td>Shipley Europe Ltd</td>
			<td>44090</td>
			<td>Pattern, electroplating</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Microposit MF-26A developer</td>
			<td>Shipley Europe Ltd</td>
			<td>31200</td>
			<td>Develop SC 1827</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Tetramethylammonium hydroxide</td>
			<td>Sigma-Aldrich</td>
			<td>334901</td>
			<td>Bulk Si etch</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Hydrofluroic acid</td>
			<td>Sciencelab.com</td>
			<td>SLH2227</td>
			<td>Silicon dioxide etch</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Sulfuric acid</td>
			<td>Sciencelab.com</td>
			<td>SLS2539</td>
			<td>wafer clean</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Hydrogen peroxide</td>
			<td>Sciencelab.com</td>
			<td>SLH1552</td>
			<td>Wafer clean</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Transene Sulfite Gold TSG-250</td>
			<td>Transense</td>
			<td>110-TSG-250</td>
			<td>Au electroplating solution</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Baker PRS-3000 Positive Resist Stripper</td>
			<td>Mallinckrodt Baker</td>
			<td>6403</td>
			<td>Photoresist stripper</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Gold etchant type TFA</td>
			<td>Transense</td>
			<td>060-0015000</td>
			<td>Au etch</td>
		</tr>
	</tbody>
</table>

real-time dc-dynamic biasing method for switching time improvement in severely underdamped fringing-field electrostatic mems actuators

Meccanicamente MEMS elettrostatico frangente campo sottosmorzato attuatori sono ben noti per il loro funzionamento commutazione veloce in risposta ad un gradino unitario tensione di polarizzazione in ingresso. Tuttavia, il compromesso per le prestazioni di commutazione migliorata è un tempo relativamente lungo assestamento per raggiungere ogni altezza gap in risposta a varie tensioni applicate. Transient applicata forme d&#39;onda di polarizzazione sono impiegati per facilitare i tempi di commutazione ridotti per elettrostatiche MEMS frangente campo attuatori con fattori di alta qualità meccaniche. Rimozione del substrato sottostante dell&#39;attuatore frangente campo crea l&#39;ambiente a basso smorzamento meccanico necessario per testare efficacemente il concetto. La rimozione del substrato sottostante ha anche un miglioramento sostanziale delle prestazioni affidabilità del dispositivo con riferimento a guasti dovuti a fenomeni di incollaggio. Sebbene polarizzazione DC-dinamica è utile per migliorare il tempo di assestamento, la slew rate richiesti per i dispositivi tipici MEMS possono collocare requisiti aggressivi sulla carica pumps per completamente integrata disegni on-chip. Inoltre, ci possono essere sfide che integrano la rimozione del substrato passo verso la CMOS commerciali fasi di elaborazione back-end-of-line. Validazione sperimentale di attuatori fabbricati dimostra un miglioramento di 50 volte nel tempo di commutazione rispetto al passo polarizzazione risultati convenzionali. Rispetto ai calcoli teorici, i risultati sperimentali sono in buon accordo.

La configurazione in Figura 4 viene utilizzata per catturare la flessione rispetto al momento le caratteristiche dei ponti MEMS. Utilizzando il vibrometro laser Doppler nella sua modalità di misurazione continua, i parametri di tensione e di tempo precisi possono essere risultate una minima oscillazione del fascio per l&#39;altezza desiderata gap. La Figura 5 illustra un esempio di deflessione del fascio corrispondente all&#39;altezza 60 V gap. Si è visto che la quasi totalità delle ...

Watch this Scientific Journal Video about Real-Time DC-dynamic Biasing Method for Switching Time Improvement in Severely Underdamped Fringing-field Electrostatic MEMS Actuators at JoVE.com

Real-Time DC-dynamic Biasing Method for Switching Time Improvement in Severely Underdamped Fringing-field Electrostatic MEMS Actuators

Il design robusto dispositivo di frange di campo elettrostatico attuatori MEMS risultati in condizioni di smorzamento squeeze film intrinsecamente bassi e lunghi tempi di assestamento durante l&#39;esecuzione di operazioni di commutazione con passo polarizzazione convenzionale. Commutazione miglioramento del tempo con forme d&#39;onda DC-dinamici in tempo reale riduce il tempo di assestamento di frange campo MEMS attuatori durante le transizioni tra up-to-down e down-to-up Stati.

Real-Time DC-dinamica Metodo di polarizzazione per il tempo di commutazione miglioramento Severamente sottosmorzato frangente campo elettrostatico MEMS Attuatori

Mechanically underdamped electrostatic fringing-field MEMS actuators are well known for their fast switching operation in response to a unit step input ...

real-time-dc-dynamic-biasing-method-for-switching-time-improvement

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Engineering

10.2K Views.  University of California, Davis.  Il design robusto dispositivo di frange di campo elettrostatico attuatori MEMS risultati in condizioni di smorzamento squeeze film intrinsecamente bassi e lunghi tempi di assestamento durante l'esecuzione di operazioni di commutazione con passo polarizzazione convenzionale. Commutazione miglioramento del tempo con forme d'onda DC-dinamici in tempo reale riduce il tempo di assestamento di frange campo MEMS attuatori durante le transizioni tra up-to-down e down-to-...

Video: Real-Time DC-dynamic Biasing Method for Switching Time Improvement in Severely Underdamped Fringing-field Electrostatic MEMS Actuators

Fabrication Process of Silicone-based Dielectric Elastomer Actuators

This contribution demonstrates the fabrication process of dielectric elastomer transducers (DETs). DETs are stretchable capacitors consisting of an elastomeric dielectric membrane sandwiched between two compliant electrodes. The large actuation strains of these transducers when used as actuators (over 300% area strain) and their soft and compliant nature has been exploited for a wide range of applications, including electrically tunable optics, haptic feedback devices, wave-energy harvesting, deformable cell-culture devices, compliant grippers, and propulsion of a bio-inspired fish-like airship. In most cases, DETs are made with a commercial proprietary acrylic elastomer and with hand-applied electrodes of carbon powder or carbon grease. This combination leads to non-reproducible and slow actuators exhibiting viscoelastic creep and a short lifetime. We present here a complete process flow for the reproducible fabrication of DETs based on thin elastomeric silicone films, including casting of thin silicone membranes, membrane release and prestretching, patterning of robust compliant electrodes, assembly and testing. The membranes are cast on flexible polyethylene terephthalate (PET) substrates coated with a water-soluble sacrificial layer for ease of release. The electrodes consist of carbon black particles dispersed into a silicone matrix and patterned using a stamping technique, which leads to precisely-defined compliant electrodes that present a high adhesion to the dielectric membrane on which they are applied.

This manuscript shows the fabrication process for the manufacture of dielectric elastomer soft actuators based on silicone membranes. The three key stages of production are presented in detail: blade casting of thin silicone membranes; pad printing of compliant electrodes; and the assembly of all the components.

Fabbricazione Processo di base di silicone elastomero dielettrici Attuatori

This contribution demonstrates the fabrication process of dielectric elastomer transducers (DETs). DETs are stretchable capacitors consisting of an ...

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Ingegneria

Compact Lens-less Digital Holographic Microscope for MEMS Inspection and Characterization

A micro-electro-mechanical-system (MEMS) is a widely used component in many industries, including energy, biotechnology, medical, communications, and automotive. However, effective inspection and characterization metrology systems are needed to ensure the functional reliability of MEMS. This study presents a system based on digital holography as a tool for MEMS metrology. Digital holography has gained increasing attention in the past 20 years. With the fast development and decreasing cost of sensor arrays, resolution of such systems has increased broadening potential applications. Thus, it has attracted attention from both research and industry sides as a potential reliable tool for industrial metrology. Indeed, by recording the interference pattern between an object beam (which contains sample height information) and a reference beam on a CCD camera, one can retrieve the quantitative phase information of an object. However, most of digital holographic systems are bulky and thus not easy to implement on industry production lines. The novelty of the system presented is that it is lens-less and thus very compact. In this study, it is shown that the Compact Digital Holographic Microscope (CDHM) can be used to evaluate several characteristics typically consider as criteria in MEMS inspections. The surface profiles of MEMS in both static and dynamic conditions are presented. Comparison with AFM is investigated to validate the accuracy of the CDHM.

We present a compact reflection digital holographic system (CDHM) for inspection and characterization of MEMS devices. A lens-less design using a diverging input wave providing natural geometrical magnification is demonstrated. Both static and dynamic studies are presented.

Lens-meno compatta digitale olografico microscopio per MEMS di ispezione e caratterizzazione

A micro-electro-mechanical-system (MEMS) is a widely used component in many industries, including energy, biotechnology, medical, communications, and ...

Free-form Light Actuators &#8212; Fabrication and Control of Actuation in Microscopic Scale

Liquid crystalline elastomers (LCEs) are smart materials capable of reversible shape-change in response to external stimuli, and have attracted researchers&#39; attention in many fields. Most of the studies focused on macroscopic LCE structures (films, fibers) and their miniaturization is still in its infancy. Recently developed lithography techniques, e.g., mask exposure and replica molding, only allow for creating 2D structures on LCE thin films. Direct laser writing (DLW) opens access to truly 3D fabrication in the microscopic scale. However, controlling the actuation topology and dynamics at the same length scale remains a challenge.
In this paper we report on a method to control the liquid crystal (LC) molecular alignment in the LCE microstructures of arbitrary three-dimensional shape. This was made possible by a combination of direct laser writing for both the LCE structures as well as for micrograting patterns inducing local LC alignment. Several types of grating patterns were used to introduce different LC alignments, which can be subsequently patterned into the LCE structures. This protocol allows one to obtain LCE microstructures with engineered alignments able to perform multiple opto-mechanical actuation, thus being capable of multiple functionalities. Applications can be foreseen in the fields of tunable photonics, micro-robotics, lab-on-chip technology and others.

Free-form Light Actuators &amp;#8212; Fabrication and Control of Actuation in Microscopic Scale

Here, we fabricate 3D polymeric micro/nano structures in which both the shape and the molecular alignment can be engineered with nanometer scale accuracy by the use of direct laser writing. Light induced deformation of several types of liquid crystalline elastomer microstructures can be controlled in the microscopic scale.

Free-forma Attuatori Light - Fabbricazione e Controllo di attuazione in scala microscopica

Liquid crystalline elastomers (LCEs) are smart materials capable of reversible shape-change in response to external stimuli, and have attracted ...

Fabrication of 3D Carbon Microelectromechanical Systems (C-MEMS)

A wide range of carbon sources are available in nature, with a variety of micro-/nanostructure configurations. Here, a novel technique to fabricate long and hollow glassy carbon microfibers derived from human hairs is introduced. The long and hollow carbon structures were made by the pyrolysis of human hair at 900 &#176;C in a N2 atmosphere. The morphology and chemical composition of natural and pyrolyzed human hairs were investigated using scanning electron microscopy (SEM) and electron-dispersive X-ray spectroscopy (EDX), respectively, to estimate the physical and chemical changes due to pyrolysis. Raman spectroscopy was used to confirm the glassy nature of the carbon microstructures. Pyrolyzed hair carbon was introduced to modify screen-printed carbon electrodes ; the modified electrodes were then applied to the electrochemical sensing of dopamine and ascorbic acid. Sensing performance of the modified sensors was improved as compared to the unmodified sensors. To obtain the desired carbon structure design, carbon micro-/nanoelectromechanical system (C-MEMS/C-NEMS) technology was developed. The most common C-MEMS/C-NEMS fabrication process consists of two steps: (i) the patterning of a carbon-rich base material, such as a photosensitive polymer, using photolithography; and (ii) carbonization through the pyrolysis of the patterned polymer in an oxygen-free environment. The C-MEMS/NEMS process has been widely used to develop microelectronic devices for various applications, including in micro-batteries, supercapacitors, glucose sensors, gas sensors, fuel cells, and triboelectric nanogenerators. Here, recent developments of a high-aspect ratio solid and hollow carbon microstructures with SU8 photoresists are discussed. The structural shrinkage during pyrolysis was investigated using confocal microscopy and SEM. Raman spectroscopy was used to confirm the crystallinity of the structure, and the atomic percentage of the elements present in the material before and after pyrolysis was measured using EDX.

Fabrication of 3D Carbon Microelectromechanical Systems C-MEMS

Long and hollow glassy carbon microfibers were fabricated based on the pyrolysis of a natural product, human hair. The two fabrication steps of carbon microelectromechanical and carbon nanoelectromechanical systems, or C-MEMS and C-NEMS, are: (i) photolithography of a carbon-rich polymer precursor and (ii) pyrolysis of the patterned polymer precursor.

Fabbricazione di sistemi microelettromeccanici a carbonio 3D (C-MEMS)

A wide range of carbon sources are available in nature, with a variety of micro-/nanostructure configurations. Here, a novel technique to fabricate long ...

Design and Characterization Methodology for Efficient Wide Range Tunable MEMS Filters

Here, we demonstrate the advantages of the laser Doppler vibrometer (LDV) over conventional techniques (the network analyzer), as well as the techniques to create an application-based microelectromechanical systems (MEMS) filter and how to use it efficiently (i.e., tuning the tuning-capability and avoiding both failure and stiction). LDV enables crucial measurements that are impossible with the network analyzer, such as higher mode detection (highly sensitive biosensor application) and resonance measurement for very small devices (fast prototyping). Accordingly, LDV was used to characterize the frequency tuning range and resonance frequency at different modes of the MEMS filters built for this study. This wide range frequency tuning mechanism is based simply on Joule heating from the embedded heaters and relatively high thermal stress with respect to the temperature of a fixed-fixed beam. However, we demonstrate that another limitation of this method is the resulting high thermal stress, which can burn the devices. Further improvement was achieved and shown for the first time in this study, such that the tuning capability was increased by 32% through an increase in the applied DC bias voltage (25 V to 35 V) between the two adjacent beams. This important finding eliminates the need for the extra Joule heating at the wider frequency tuning range. Another possible failure is through stiction and requirement of structure optimization: We propose a simple and easy technique of low frequency square wave signal application that can successfully separate the beams and eliminates the need for the more sophisticated and complicated methods given in the literature. The above findings necessitate a design methodology, and so we also provide an application-based design.

A protocol for a fixed-fixed beam design using a laser Doppler vibrometer (LDV), including the measurement of frequency tuning, modification of tuning capability, and avoidance of device failure and stiction, is presented. The superiority of the LDV method over the network analyzer is demonstrated due to its higher mode capability.

Progettazione e nella metodologia di caratterizzazione per efficiente ampio intervallo sintonizzabile MEMS filtri

Here, we demonstrate the advantages of the laser Doppler vibrometer (LDV) over conventional techniques (the network analyzer), as well as the techniques ...

Fabrication of Soft Pneumatic Network Actuators with Oblique Chambers

Soft pneumatic network actuators have become one of the most promising actuation devices in soft robotics which benefits from their large bending deformation and low input. However, their monotonous bending motion form in two-dimensional (2-D) space keeps them away from wide applications. This paper presents a detailed fabrication method of soft pneumatic network actuators with oblique chambers, to explore their motions in three-dimensional (3-D) space. The design of oblique chambers enables actuators with tunable coupled bending and twisting capabilities, which gives them the possibility to move dexterously in flexible manipulators, to become biologically inspired robots and medical devices. The fabrication process is based on the molding method, including the silicone elastomer preparation, chamber and base parts fabrication, actuator assembly, tubing connections, checks for leaks, and actuator repair. The fabrication method guarantees the rapid manufacturing of a series of actuators with only a few modifications in the molds. The test results show the high quality of the actuators and their prominent bending and twisting capabilities. Experiments of the gripper demonstrate the advantages of the development in adapting to objects with different diameters and providing sufficient friction.

Here we present a fabrication method of soft pneumatic network actuators with oblique chambers. The actuators are capable of generating coupled bending and twisting motions, which broadens their application in soft robotics.

Fabbricazione di morbida rete pneumatica attuatori con obliquo Chambers

Soft pneumatic network actuators have become one of the most promising actuation devices in soft robotics which benefits from their large bending ...

Optimized Sealing Process and Real-Time Monitoring of Glass-to-Metal Seal Structures

Residual stress is an essential factor to keeping the hermeticity and robustness of a glass-to-metal seal structure. The purpose of this report is to demonstrate a novel protocol to characterize and measure residual stress in a glass-to-metal seal structure without destroying the insulation and hermeticity of sealing materials. In this research, a femto-laser inscribed fiber Bragg grating sensor is used. The glass-to-metal seal structure that is measured consists of a metal shell, sealing glass, and Kovar conductor. To make the measurements worthwhile, the specific heat treatment of metal-to-glass seal (MTGS) structure is explored to obtain the model with best hermeticity. Then, the FBG sensor is embedded into the path of sealing glass and becomes well-fused with the glass as the temperature cools to RT. The Bragg wavelength of FBG shifts with the residual stress generated in sealing the glass. To calculate the residual stress, the relationship between Bragg wavelength shift and strain is applied, and the finite element method is also used to make the results reliable. The online monitoring experiments of residual stress in sealing glass are carried out at different loads, such as high temperature and high pressure, to broaden functions of this protocol in harsh environments.

Key procedures to optimize the sealing process and achieve real-time monitoring of the metal-to-glass seal (MTGS) structure are described in detail. The embedded fiber Bragg grating (FBG) sensor is designed to achieve online monitoring of temperature and high-level residual stress in the MTGS with simultaneous environmental pressure monitoring.

Processo di sigillamento ottimizzato e monitoraggio in tempo reale delle strutture sigillanti vetro-metallo

Residual stress is an essential factor to keeping the hermeticity and robustness of a glass-to-metal seal structure. The purpose of this report is to ...

Rapid Manufacturing of Thin Soft Pneumatic Actuators and Robots

This protocol describes a method for rapid manufacturing of soft pneumatic actuators and robots with an ultrathin form factor using a heat press and a laser cutter machine. The method starts with the lamination of thermoplastic polyurethane (TPU) sheets using a heat press for 10 min at the temperature of ~93 &#176;C. Next, the parameters of the laser cutter machine are optimized to produce a rectangular balloon with maximum burst pressure. Using the optimized parameters, the soft actuators are laser cut/welded three times sequentially. Next, a dispensing needle is attached to the actuator, allowing it to be inflated. The effect of geometrical parameters on the deflection of the actuator are studied systematically by varying the channel width and length. Finally, the performance of the actuator is characterized using an optical camera and a fluid dispenser. Conventional fabrication methods of soft pneumatic actuators based on silicone molding are time consuming (several hours). They also result in strong but bulky actuators, which limits the actuator&#8217;s applications. Moreover, microfabrication of thin pneumatic actuators is both time-consuming and expensive. The proposed manufacturing method in the current work resolves these issues by introducing a fast, simple, and cost-effective fabrication method of ultrathin pneumatic actuators.

This protocol describes a method for rapid manufacturing of soft pneumatic actuators and robots with a thin form factor. The fabrication method starts with lamination of thermoplastic polyurethane (TPU) sheets followed by laser cutting/welding of a two-dimensional pattern to form actuators and robots.

Produzione rapida di attuatori e robot pneumatici sottili e morbidi

This protocol describes a method for rapid manufacturing of soft pneumatic actuators and robots with an ultrathin form factor using a heat press and a ...

In Situ Transmission Electron Microscopy with Biasing and Fabrication of Asymmetric Crossbars Based on Mixed-Phased a-VOx

Resistive switching crossbar architecture is highly desired in the field of digital memories due to low cost and high-density benefits. Different materials show variability in resistive switching properties due to the intrinsic nature of the material used, leading to discrepancies in the field because of underlying operation mechanisms. This highlights a need for a reliable technique to understand mechanisms using nanostructural observations. This protocol explains a detailed process and methodology of in&#160;situ nanostructural analysis as a result of electrical biasing using transmission electron microscopy (TEM). It provides visual and reliable evidence of underlying nanostructural changes in real time memory operations. Also included is the methodology of fabrication and electrical characterizations for asymmetric crossbar structures incorporating amorphous vanadium oxide. The protocol explained here for vanadium oxide films can be easily extended to any other materials in a metal-dielectric-metal sandwiched structure. Resistive switching crossbars are predicted to serve the programmable logic and neuromorphic circuits for next-generation memory devices, given the understanding of the operation mechanisms. This protocol reveals the switching mechanism in a reliable, timely, and cost-effective way in any type of resistive switching materials, and thereby predicts the device&#39;s applicability.

In Situ Transmission Electron Microscopy with Biasing and Fabrication of Asymmetric Crossbars Based on Mixed-Phased a-VOx

Presented here is a protocol for analyzing nanostructural changes during in&#160;situ biasing with transmission electron microscopy (TEM) for a stacked metal-insulator-metal structure. It has significant applications in resistive switching crossbars for the next generation of programmable logic circuits and neuromimicking hardware, to reveal their underlying operation mechanisms and practical applicability.

Microscopia elettronica a trasmissione in situ con distorsione e fabbricazione di traverse asimmetriche basate su a -VO x afasemista

Resistive switching crossbar architecture is highly desired in the field of digital memories due to low cost and high-density benefits. Different ...

Fabrication of Carbon-Based Ionic Electromechanically Active Soft Actuators

Ionic electromechanically active capacitive laminates are a type of smart material that move in response to electrical stimulation. Due to the soft, compliant and biomimetic nature of this deformation, actuators made of the laminate have received increasing interest in soft robotics and (bio)medical applications. However, methods to easily fabricate the active material in large (even industrial) quantities and with a high batch-to-batch and within-batch repeatability are needed to transfer the knowledge from laboratory to industry. This protocol describes a simple, industrially scalable and reproducible method for the fabrication of ionic carbon-based electromechanically active capacitive laminates and the preparation of actuators made thereof. The inclusion of a passive and chemically inert (insoluble) middle layer (e.g., a textile-reinforced polymer network or microporous Teflon) distinguishes the method from others. The protocol is divided into five steps: membrane preparation, electrode preparation, current collector attachment, cutting and shaping, and actuation. Following the protocol results in an active material that can, for example, compliantly grasp and hold a randomly shaped object as demonstrated in the article.

This article describes a fast and simple manufacturing process of ionic electromechanically active composite materials for actuators in biomedical, biomimetic and soft robotics applications. The key fabrication steps, their importance for the actuators&#39; final properties, and some of the main characterization techniques are described in detail.

Fabbricazione di attuatori morbidi ionici ad attività in carbonio

Ionic electromechanically active capacitive laminates are a type of smart material that move in response to electrical stimulation. Due to the soft, ...