Electromechanical Actuators (electromechanical + actuator)

Distribution by Scientific Domains


Selected Abstracts


Investigating static and dynamic characteristics of electromechanical actuators (EMA) with MATLAB GUIs

COMPUTER APPLICATIONS IN ENGINEERING EDUCATION, Issue 2 2010
Gursel Sefkat
Abstract This paper deals with the design of an electromechanical device considering some prescribed performance requirements, and static and dynamic analysis of this device are carried out. In studying the transient response of such a system, as part of dynamic analysis, two methods mostly used finite element method (FEM) and finite differences method (FDM). However, these methods need much CPU time. In this work, a computer simulator program is developed for an EMA. This technique is implemented in the MATLAB-Simulink environment and tested for different design tasks such as electromagnetic valves or electromechanical brakes etc. Furthermore, by using GUIDE tools within MATLAB, a simple useful and user-friendly GUI structure is developed to provide a visual approach to design and analysis process. © 2009 Wiley Periodicals, Inc. Comput Appl Eng Educ 18: 383,396, 2010; Published online in Wiley InterScience (www.interscience.wiley.com); DOI 10.1002/cae.20279 [source]


High Breakdown Field Dielectric Elastomer Actuators Using Encapsulated Polyaniline as High Dielectric Constant Filler

ADVANCED FUNCTIONAL MATERIALS, Issue 19 2010
Martin Molberg
Abstract A novel method allowing rapid production of reliable composites with increased dielectric constant and high dielectric strength for dielectric elastomer actuators (DEA) is reported. The promising approach using composites of conductive particles and insulating polymers generally suffers from low breakdown fields when applied to DEA devices. The present publication shows how to overcome this deficiency by using conductive polyaniline (PANI) particles encapsulated into an insulating polymer shell prior to dispersion. PANI particles are encapsulated using miniemulsion polymerization (MP) of divinylbenzene (DVB). The encapsulation process is scaled up to approximately 20 g particles per batch. The resulting particles are used as high dielectric constant (,,) fillers. Composites in a polydimethylsiloxane (PDMS) matrix are prepared and the resulting films characterized by dielectric spectroscopy and tensile tests, and evaluated in electromechanical actuators. The composite films show a more than threefold increase in ,,, breakdown field strengths above 50 V ,m,1, and increased strain at break. These novel materials allow tuning the actuation strain or stress output and have potential as materials for energy harvesting. [source]


Shipboard Fluid System Diagnostic Indicators Using Non-Intrusive Load Monitoring

NAVAL ENGINEERS JOURNAL, Issue 2 2007
GREGORY R. MITCHELL
Field studies have demonstrated that it is possible to evaluate the state of many shipboard systems by analyzing the electrical power that is drawn by electromechanical actuators. This paper demonstrates how a device known as a non-intrusive load monitor (NILM) uses only electrical power data to detect several critical faults in shipboard fluid systems. Using the example of reverse-osmosis units installed aboard the US Coast Guard's Medium Endurance Cutters, it is shown that the NILM can provide ship's force with a highly reliable real-time system monitoring capability. [source]


Millimetre-scale bubble-like dielectric elastomer actuators

POLYMER INTERNATIONAL, Issue 3 2010
Federico Carpi
Abstract Hydrostatic coupling has recently been reported as a means to improve the versatility and safety of electromechanical actuators based on dielectric elastomers (DEs). Hydrostatically coupled DE actuators rely on an incompressible fluid that mechanically couples a DE-based active part to a passive part interfaced to the load. The work reported here was aimed at developing millimetre-scale bubble-like versions of such transducers. Silicone-made oil-filled actuators were manufactured as both single units and arrays of parallel elements. Bubbles had a base diameter of 6 mm and were driven up to a voltage of 2.25 kV, applied across a silicone film with a thickness of 42 µm. Active relative displacements and stresses up to 18% and 2.2 kPa, respectively, were recorded with static driving. Dynamic investigations reported a ,3 dB bandwidth of the order of 100 Hz and a resonance frequency of about 250 Hz. Millimetre-scale hydrostatically coupled DE actuators might play a useful role in several fields of application. Among them, we are currently exploring novel tactile displays and cutaneous stimulators, made of wearable, distributed and flexible devices. Although further miniaturization is required for high-resolution uses, this technology holds promise to properly combine performance with safe and compliant interfaces with users, low specific weight, no acoustic noise and low cost. Copyright © 2009 Society of Chemical Industry [source]