9,083 Results Found

The actuation of silicone/ethanol soft composite material-actuators is based on the phase change of ethanol upon heating, followed by the expansion of the whole composite, exhibiting high actuation stress and strain. However, the low thermal conducti...

The mechanism of the inchworm motor, which overcomes the intrinsic displacement and force limitations of MEMS electrostatic actuators, has undergone constant development in the past few decades. In this work, the electrostatic actuation unit cell (AU...

Twisted polymer fibre actuators provide high torsional rotation from stimulated volume expansion, induced either by chemical fuelling, thermal stimulation, or electrochemical charging. One key limitation of these actuators is the irreversibility of t...

Small-scale, out-of-plane actuators can enable tactile interfaces; however, achieving sufficient actuator force and displacement can require larger actuators. In this work, 2-mm² out-of-plane microactuators were created, and were demonstrated to outp...

Compared with traditional rigid robots, soft robots have high flexibility, low stiffness, and adaptability to unstructured environments, and as such have great application potential in scenarios such as fragile object grasping and human machine inter...

As a key enabler for future aviation technology, the use of servo electromechanical actuation offers new opportunities to transition innovative structural concepts, such as biomimicry morphing structures, from basic research to new commercial aircraf...

Previous work has shown that floor slabs make up most of the material mass of building structures and are typically made of reinforced concrete. Considering the associated resource consumption and greenhouse gas emissions, new approaches are needed i...

Actuators intended for human–machine interaction systems are usually designed to be mechanically compliant. Conventional actuators are not suitable for this purpose due to typically high stiffness. Advanced powered prosthetic and orthotic devic...

Novel miniature-scale bistable actuators are developed, which consist of two antagonistically coupled buckling shape memory alloy (SMA) beams. Two SMA films are designed as buckling SMA beams, whose memory shapes are adjusted to have opposing bucklin...

Performance of the shape memory alloy (SMA) coil spring actuator in cyclic actuation as an artificial muscle is strongly related to the mechanical design of the coil geometry. This paper proposes a practical design method for improving the frequency...

Artificial muscle actuator has been devoted to replicate the function of biological muscles, playing an important part of an emerging field at inter-section of bionic, mechanical, and material disciplines. Most of these artificial muscles possess the...

In order to provide a simplified and low-cost solution of the terminal for a distributed actuation system, this paper proposes an electro-hydrostatic actuator (EHA) based on the linear drive principle. The proposed actuator is directly driven by a li...

The engineering of actuation systems for active exoskeletons presents a significant challenge due to the stringent demands for mass reduction and compactness, coupled with complex specifications for actuator dynamics and stroke length. This challenge...

Electroactive polymer (EAP) actuators are an example of a novel soft material device that can be used for several applications including artificial muscles and lenses. The field of EAPs can be broken down into a few fields; however, the field that wi...

A computational study was conducted on flows over an NACA0015 airfoil with dielectric barrier discharge (DBD) plasma. The separated flows were controlled by a DBD plasma actuator installed at the 5% chord position from the leading edge, where operate...

The versatility of the form factors of thermal shape memory alloys (SMA) in combination with their unique actuation and sensing abilities allow for the design and construction of innovative multifunctional systems. Despite the considerable number of...

The microvalve is one of the most important components in microfluidics. With decades of development, the microvalve has been widely used in many industries such as life science, chemical engineering, chip, and so forth. This paper presents a compreh...

We present the design, simulation, and characterization of a magnetic shape-memory alloy (MSMA) film actuator that transitions from bistable switching to resonant self-actuation when subjected to a stationary heat source. The actuator design comprise...

Morphing aircraft offer superior properties as compared to non-morphing aircraft. They can achieve this by adapting their shape depending on the requirements of various conflicting flight conditions. These shape changes are often associated with larg...

Controllable deformation of liquid metal by electrocapillary actuation (ECA) is empirically characterized in fluidic channels at the sub-millimeter-length scale. In 100-µm-deep channels of varying widths, the Galinstan liquid metal could move at velo...

Exoskeletons are robots that closely interact with humans and that are increasingly used for different purposes, such as rehabilitation, assistance in the activities of daily living (ADLs), performance augmentation or as haptic devices. In the last f...

This paper studies the working principles of antagonistic magneto-rheological (MR) actuators, i.e., a combination of an electric motor and a pair of MR clutches in an antagonistic configuration, for compliant actuation in robotics. The study focuses...

Within the framework of the Clean Sky-JTI (Joint Technology Initiative) project, the design and technological demonstration of a novel wing flap architecture were addressed. Research activities were carried out to substantiate the feasibility of morp...

The effect of stress depolarization will cause actuation function degradation of a piezoelectric actuator, which can eventually trigger function failure of the piezoelectric smart structure system. In the present study, we experimentally demonstrate...

Ionic polymer metal composites (IPMCs) with various thicknesses of 1, 2, 4, and 6 nafion films (denoted as 1-film, 2-film, 4-film and 6-film, respectively) are fabricated, and their characterization and actuation performances are then investigated. T...

Currently, energy demand is more significant than ever due to population growth and advances in recent technologies. In order to supply more energy while maintaining a healthy environment, renewable energy resources are employed. This paper proposes...

Soft robots, which exhibit distinguishing features in terms of compliance, adaptability, and safety, have been expansively adopted in various niche applications. For soft robots, innovative actuators have been designed based on smart materials enabli...

This study investigated the electrochemical actuation behavior of nanoporous material during the capacitive process. The length change of nanoporous gold (npg) was in situ investigated in a liquid environment using the dilatometry technique. The mech...

Untethered, controllable, mobile microrobots have been proposed for numerous applications, ranging from micro-manipulation, in vitro tasks (e.g., operation of microscale biological substances) to in vivo applications (e.g., targeted drug delivery; br...

Objective: A modeling and simulation tool, OpenSim, was used to determine the optimal relationship between actuator stiffness and actuation timing of a passive ankle exoskeleton for reducing metabolic costs during walking. We hypothesized that the ab...

Vast applications and services have been enabled as the number of mobile or sensing devices with communication capabilities has grown. However, managing the devices, integrating networks or combining services across different networks has become a ne...

Increasing performance in modern hydraulics is achieved by a close investigation of possible enhancements of its components. Prior research has pointed out that electromechanical actuators can form suitable alternatives to hydraulically piloted contr...

In this study, a numerical investigation is conducted on combustion-driven pulsed-jet actuation to control the flow around a lifting surface. Based on relevant experimental measurements and computations, high-speed jets are generated from the impulsi...

Similar to biological muscles, the actuator materials can function as artificial muscles by directly converting an external stimulus in the form of electrical or chemical energy into a mechanical response through the reversible changes in material di...

In heterogeneous wireless networked control systems (WNCSs), the age of information (AoI) of the actuation update and actuation update cost are important performance metrics. To reduce the monetary cost, the control system can wait for the availabili...

This work presents the results of the experimental and theoretical study of the static pull-in of tilting actuation executed by a hybrid levitation micro-actuator (HLMA) based on the combination of inductive levitation and electrostatic actuation. A...

The hydrostatic actuation system based on linear actuators improves the complex piston force and long transmission path of the traditional electro-hydrostatic actuator (EHA). However, new nonlinear factors in the linear actuator and direct-driven pis...

Millions of electrostatically actuatable micromirror arrays have been arranged in between windowpanes in inert gas environments, enabling active daylighting in buildings for illumination and climatization. MEMS smart windows can reduce energy consump...

In films of conducting polymers, the electrochemical reaction(s) drive the simultaneous variation of different material properties (reaction multifunctionality). Here, we present a parallel study of actuation-sensing-energy storage triple functionali...

In this paper, we report a novel laterally actuated Radio Frequency (RF) Microelectromechanical Systems (MEMS) switch, which is based on a combination of electrothermal actuation and electrostatic latching hold. The switch takes the advantages of bot...

A nature-inspired musculoskeletal system is designed and developed to examine the principle of nonlinear elastic energy storage–release for robotic applications. The musculoskeletal system architecture consists of elastically rigid segments and...

Dielectric elastomers (DEs) represent a class of electroactive polymers that deform due to electrostatic attraction between oppositely charged electrodes under a varying electric field. Over the last couple of decades, DEs have garnered considerable...

Operators of mobile platforms that employ hydraulic actuation, such as excavators, seek more efficient power transfer from source to load. Pump-controlled architectures achieve greater efficiency than valve-controlled architectures but exhibit poor t...

Hydrogel is a type of soft smart material and is responsive to stimuli. In the development of actuation in hydrogel, electrical actuation features a fast and universal strategy which is favored in the engineering system. Due to the difficulty in dire...

The graphene nanosheets (GNS)/polydimethylsiloxane (PDMS) composite films with out-of-plane dielectric actuation behavior were prepared through a layer-by-layer spin coating process. The GNS-PDMS/PDMS composite films with 1~3 layers of GNS-PDMS films...

Jamming is a popular and versatile soft robotic mechanism, enabling new systems to be developed that can achieve high stiffness variation with minimal volume variation. Numerous applications have been reported, including deep-sea sampling, industrial...

The lower limb exoskeleton investigated in this work actively supports the knee and hip and is intended to provide full motion support during gait. Parallel elastic actuators are integrated into the hip joints to improve the energy efficiency in gait...

The present contribution aims to analyze and highlight the potential of piezoelectric materials in actuation and sensing duties, obtaining reliable high-precision outcomes in cutting-edge applications including medical interventions. This involves hi...

The current research focuses on modeling the lift response due to dynamic (time-varying) “burst-type” actuation on a stalled airfoil. Here, the “burst-type” actuation refers to the synthetic jet (generated from the actuator) that is used for flow sep...

In this paper, we report a method of implementing a universal volumetric haptic actuation platform which can be adapted to fit a wide variety of visual displays with flat surfaces. This platform aims to enable the simulation of the 3D features of inp...