scholarly journals Study on Transformer JED Cap Actuation Systems in the Field of Very Strong Electromagnetic Disturbances

2020 ◽  
Vol 11 (4) ◽  
pp. 45-60
Author(s):  
Andrzej M. FARYŃSKI ◽  
Tomasz BRODNIEWICZ ◽  
Jarosłąw DĘBIŃSKI ◽  
Łukasz SŁONKIEWICZ ◽  
Radosław SZYMAŃSKI ◽  
...  
Keyword(s):  
Outer Diameter ◽  
Actuation System ◽  
Electric Current Pulses ◽  
Current Conductor ◽  
External Electromagnetic Fields ◽  
Current Axis ◽  
Institute Of Technology ◽  
Actuation Systems ◽  
Electromagnetic Disturbances ◽  
Open Core

This work presents the results of research on the influence of strong external electromagnetic fields on the operation of JED spark caps activated by transformer systems. The tests were carried out in order to determine the conditions of safe use of JED caps installed in control systems of generators producing electric current pulses using the principle of an explosive magnetic field cumulation [1]. For this purpose, the measurements of the voltages induced in the transformer JED spark cap actuation system were performed using sinusoidal external current with an amplitude of 10 kA for a period of 15 microseconds. This current flowed at a distance from d = 10 mm to d = 40 mm from the axis of the ferrite cores of the applied transformers: a closed core with an outer diameter of 20 mm, an inner diameter of 10 mm and a height of 10 mm and an open core with a diameter of 6 mm and a length of 25 mm. The transformers used in Air Force Institute of Technology (AFIT) were placed alternately parallel and perpendicular to the axis of the current conductor. In the case of a transformer with a cylindrical open core perpendicular to the current axis, the induced voltages significantly exceeded the values at which the caps were activated (about 2 kV) and became lower than these values at d of about 40 mm. Toroidal closed cores provided induced voltages of up to 200 V (10 times lower) for all configurations tested. The measurements were performed using a system and methods developed at AFIT.

Design, modeling, and analysis of wedge-based actuator with application to clutch-to-clutch shift

2017 ◽  
Vol 232 (9) ◽  
pp. 1149-1166
Author(s):  
Fengyu Liu ◽  
Li Chen ◽  
Jian Yao ◽  
Chunhao Lee ◽  
Chi-kuan Kao ◽  
...  
Keyword(s):  
Dynamic Models ◽  
Fast Response ◽  
Physical Structure ◽  
Modeling And Analysis ◽  
Shift Quality ◽  
Actuation System ◽  
Automatic Transmissions ◽  
Potential Alternative ◽  
Low Efficiency ◽  
Actuation Systems

Clutch-to-clutch shift technology is a key enabler for fast and smooth gear shift process for multi gear transmissions. However, conventional hydraulic actuation systems for clutches have drawbacks of low efficiency, oil leakage and inadequate robustness. Electromechanical devices offer potential alternative actuators. In this paper, a novel motor driven wedge-based clutch actuator, featuring self-reinforcement, is proposed. The design concept and physical structure are thoroughly described. Dynamic models for the actuation system and vehicle powertrain are validated by experiments. Upshift and downshift processes at different engine throttle openings, clutch clearances and friction coefficients are discussed. The results show that, the self-reinforcement ratio is tested as 9.6; at the same time, the shift quality is comparable to that of the conventional hydraulic actuated clutch in automatic transmissions in terms of the shift duration (about 1 s) and vehicle jerk (<10 m/s3). Taking advantage of fast response of the actuation DC motor, the wedge-based actuator is robust dealing with uncertain clutch clearance and friction coefficient. Therefore, the wedge-based clutch actuator has potential to provide acceptable performance for clutch-to-clutch shift.

scholarly journals Non-Conventional Actuation Mechanisms used in Mechatronic systems

2018 ◽  
Vol 3 (1) ◽  
pp. 05-10
Author(s):  
Rajiv Chaudhary ◽  
◽  
Alok Kumar Singh
Keyword(s):  
Mechanical Systems ◽  
Recent Past ◽  
Mechatronic Systems ◽  
Actuation System ◽  
Prime Movers ◽  
Overall Performance ◽  
Engine System ◽  
Mechanical Elements ◽  
Actuation Systems ◽  
Mechanical Actuation

Tracking the path of development in different Engineering disciplines, it can be easily observed that, right from the primitive stage, several tools, devices, and techniques may be identified, which happened by virtue of the evolution of human intelligence, getting transformed into various engineering applications. Although, later different engineering disciplines evolved, where most of the exhaustive development could be undertaken in that discipline. Likewise, in the field of mechanical engineering to various types of mechanical systems, according to the requirement in that field, were developed, in order to provide support of mechanization. Prime movers used to be an important part of these mechanical systems, which provided energy input as well as actuation required for providing the machines the desired kinematics. Most of the mechanical systems developed has been operated by conventional engine system using one or other fuel. Apart from the actuation by mechanical means, there are other means also through which mechanical actuation with better control, flexibility, and manipulation may be utilized in mechanical systems. A different category of systems, called Mechatronic systems has been developed in the recent past, which involves the vivid scope of use of techniques, devices, and components generally used in various other engineering fields of electrical, electronics, hydraulics, and pneumatics, etc. Subsequently, there have been several inventions, design & development which have added new levels in every field. Mechanical systems have been generally composed of various mechanical elements, which are designed to follow certain kinematics. The performance of the Actuation system plays an important role in the overall performance of the mechanical systems. There are several alternative actuation systems, which are not mechanical. These actuation systems may be categorized into electrical, electronics, hydraulic and pneumatic types. The features of these actuation systems, are so peculiar, that typical kinematic movement may be manipulated that too with more precision. Better control of mechanical systems may be realized, which is otherwise difficult with mechanical systems. In this paper, an effort has been made to review the possibilities, prospects as well as scope with various actuation systems.

Theoretical Modeling for Electroactive Polymer-Ceramic Hybrid Actuation Systems

Aerospace ◽  
2004 ◽  
Author(s):  
Tian-Bing Xu ◽  
Ji Su
Keyword(s):  
Performance Optimization ◽  
High Performance ◽  
Electroactive Polymer ◽  
Actuation System ◽  
Electromechanical Responses ◽  
Electromechanical Performance ◽  
New Type ◽  
Hybrid Actuation ◽  
Actuation Systems ◽  
Further Development

An electroactive polymer-ceramic hybrid actuation system (HYBAS) was recently developed. The HYBAS demonstrates significantly-enhanced electromechanical performance by utilizing advantages of cooperative contributions of the electromechanical responses of an electrostrictive copolymer and an electroactive single crystal. The hybrid actuation system provides not only a new type of device but also a concept to utilize different electroactive materials in a cooperative and efficient method for optimized electromechanical performance. In order to develop an effective procedure to optimize the performance of a hybrid actuation system (HYBAS), a theoretical model has been developed, based on the elastic and electromechanical properties of the materials utilized in the system and on the configuration of the device. The model also evaluates performance optimization as a function of geometric parameters, including the length of the HYBAS and the thickness ratios of the constituent components. The comparison between the model and the experimental results shows a good agreement and validates the model as an effective method for the further development of high performance actuating devices or systems for various applications.

scholarly journals Large-volume air sample system for measuring <sup>34</sup>S∕<sup>32</sup>S isotope ratio of carbonyl sulfide

2019 ◽  
Vol 12 (2) ◽  
pp. 1141-1154 ◽  
Author(s):  
Kazuki Kamezaki ◽  
Shohei Hattori ◽  
Enno Bahlmann ◽  
Naohiro Yoshida
Keyword(s):  
Diurnal Variation ◽  
Isotope Ratio ◽  
Collection Efficiency ◽  
Anthropogenic Activities ◽  
Carbonyl Sulfide ◽  
Ambient Air ◽  
Spatial And Temporal Variation ◽  
Outer Diameter ◽  
Sampling System ◽  
Institute Of Technology

Abstract. Knowledge related to sulfur isotope ratios of carbonyl sulfide (OCS or COS), the most abundant atmospheric sulfur species, remains scarce. An earlier method developed for sulfur isotopic analysis for OCS using S+ fragmentation by an isotope ratio mass spectrometer is inapplicable for ambient air samples because of the large samples required (approx. 500 L of 500 pmol mol−1 OCS). To overcome this difficulty, herein we present a new sampling system for collecting approximately 10 nmol of OCS from ambient air coupled with a purification system. Salient system features are (i) accommodation of samples up to 500 L (approx. 10 nmol) of air at 5 L min−1; (ii) portability of adsorption tubes (1∕4 in. (0.64 cm) outer diameter, 17.5 cm length, approximately 1.4 cm3 volume) for preserving the OCS amount and δ34S(OCS) values at −80 ∘C for up to 90 days and 14 days; and (iii) purification OCS from other compounds such as CO2. We tested the OCS collection efficiency of the systems and sulfur isotopic fractionation during sampling. Results show precision (1σ) of δ34S(OCS) values as 0.4 ‰ for overall procedures during measurements for atmospheric samples. Additionally, this report presents diurnal variation of δ34S(OCS) values collected from ambient air at the Suzukakedai campus of the Tokyo Institute of Technology located in Yokohama, Japan. The observed OCS concentrations and δ34S(OCS) values were, respectively, 447–520 pmol mol−1 and from 10.4 ‰ to 10.7 ‰ with a lack of diurnal variation. The observed δ34S(OCS) values in ambient air differed greatly from previously reported values of δ34S(OCS) = (4.9±0.3) ‰ for compressed air collected at Kawasaki, Japan, presumably because of degradation of OCS in cylinders and collection processes for that sample. The difference of atmospheric δ34S(OCS) values between 10.5 ‰ in Japan (this study) and ∼13 ‰ recently reported in Israel or the Canary Islands indicates that spatial and temporal variation of δ34S(OCS) values is expected due to a link between anthropogenic activities and OCS cycles. The system presented herein is useful for application of δ34S(OCS) for investigation of OCS sources and sinks in the troposphere to elucidate its cycle.

Metal Hydride Fluidic Artificial Muscle Actuation System

2008 ◽  
Vol 1129 ◽  
Author(s):  
Alexandra Vanderhoff ◽  
Kwang Kim
Keyword(s):  
Reaction Kinetics ◽  
Metal Hydride ◽  
Three Dimensional ◽  
Artificial Muscle ◽  
Actuation System ◽  
Hydride Hydrogen ◽  
Actuation Devices ◽  
Fluidic Muscle ◽  
Actuation Systems ◽  
Future Work

AbstractThe study determines the feasibility of a new actuation system that couples a fluidic artificial muscle designed by Festo [1] with a metal hydride hydrogen compressor to create a compact, lightweight, noiseless system capable of high forces and smooth actuation. An initial model for the complete system is developed. The analysis is restricted in some aspects concerning the complexity of the hydriding/dehydriding chemical process of the system and the three-dimensional geometry of the reactor, but it provides a useful comparison to other actuation devices and clearly reveals the parameters necessary for optimization of the actuation system in future work. The system shows comparable work output and has the benefits of biological muscle-like properties [2] for use in robotic systems. When compared to other previously developed metal hydride actuation systems the potential for increasing the reaction kinetics and improving the overall power output of the system is revealed. A comparison of the system to common actuation devices, including a biological muscle, shows similar stress and strain relations, but a lower power and frequency range due to the slow actuation time. Improving the reaction kinetics of the system will be the first approach to enhancing the system, along with optimization of the mass and type of metal hydride used in the reactor to produce a full actuation stoke of the fluidic muscle while minimizing system weight.

A Magnetorheological Actuation System: Part I — Testing

2007 ◽  
Author(s):  
Shaju John ◽  
Jin-Hyeong Yoo ◽  
Norman M. Wereley
Keyword(s):  
Magnetic Field ◽  
Active Vibration Control ◽  
Active Material ◽  
Wheatstone Bridge ◽  
Mr Fluids ◽  
Actuation System ◽  
Hybrid Devices ◽  
Actuation Systems ◽  
Frequency Rectification ◽  
Moving Parts

There is a demand for compact hybrid actuation systems which combines actuation and valving systems in a compact package. Such self-contained actuation systems have potential applications in the field of rotorcraft (as active pitch links) and automotive engineering (as active vibration control devices). Hybrid hydraulic actuation systems, based on frequency rectification of the high frequency motion of an active material, can be used to exploit the high bandwidth of smart material to design devices with high force and stroke. Magnetorheological (MR) fluids are active fluids whose viscosity can be changed through the application of a magnetic field. By using MR fluids as the hydraulic fluid in such hybrid devices, a valving system with no moving parts can be implemented. Such a system will be attractive in rotorcraft applications with large centrifugal force loading. Thus, MR fluids can be used to control the motion of an output cylinder. The MR fluid based valves can be configured in the form of a Wheatstone bridge to produce bi-directional motion in an output cylinder by alternately applying a magnetic field in the two arms of the bridge. In this study, the actuation is performed using a compact Terfenol-D stack driven actuator. The frequency rectification of the stack motion is done using reed valves. This actuator and valve configuration form a compact hydraulic system with fluidic valves. The advantages of such systems are that part count is low, absence of moving parts and the possibility of continuous controllability of the output cylinder. By applying varying magnetic fields in the arms of the bridge (by applying different currents to the coils), the differential pressure acting on the output cylinder can be controlled. The description of the experimental setup, the tests performed and the experimental results are presented in this paper.

On the Dynamic Response of Actuation Devices in Nonlinear Dynamics Systems

2013 ◽  
Author(s):  
Jahangir Rastegar ◽  
Dake Feng
Keyword(s):  
Nonlinear Dynamics ◽  
Dynamic Response ◽  
Control Systems ◽  
Mechanical Systems ◽  
Inertial Load ◽  
Feed Forward ◽  
Feed Forward Control ◽  
Actuation System ◽  
Actuation Devices ◽  
Actuation Systems

This paper presents a study of the dynamic response of actuation devices used in mechanical systems with nonlinear dynamics such as robot manipulators. The study shows that the actuation forces/torques provided by actuation devices can be divided into two basic groups. The first group corresponds to the components of each actuator force/torque that is “actuator motion independent”. The dynamic response of this group is relatively high and limited only by the dynamic response limitations — for the case of electrically driven actuation systems — of the driving power amplifiers, electronics, computational and signal processing devices and components. The second group corresponds to those components of the actuator forces/torques that is “actuator motion dependent”. The dynamic response of this group is relatively low and dependent on the actuator effective inertial load and actuation speed. In all mechanical systems that are properly designed, the dynamic response of the first group is significantly higher than those of the second group. By separating the required actuating forces/torques into the above two groups, the dynamic response of such nonlinear dynamics systems may be determined for a given synthesized trajectory. The information can also be used to significantly increase the performance of control systems of such mechanical systems. When a feed-forward control signal is used, the performance of the system is shown to be significantly improved by generating each one of the group of components separately considering the dynamic response of the actuation system to each one of the groups of components. An example and practical methods of implementing the proposed feed-forward control for nonlinear dynamics systems are provided.

A smart hydraulic joint for future implementation in robotic structures

Robotica ◽  
2010 ◽  
Vol 28 (7) ◽  
pp. 1045-1056 ◽  
Author(s):  
J. Berring ◽  
K. Kianfar ◽  
C. Lira ◽  
C. Menon ◽  
F. Scarpa
Keyword(s):  
Mathematical Model ◽  
Experimental Tests ◽  
Flexible Joint ◽  
Actuation System ◽  
Actuation Systems ◽  
Static Behaviour

SUMMARYA hydraulic flexible joint inspired by the actuation system of spiders is investigated in this paper. Its design and characteristics are discussed and a mathematical model is developed to describe its static behaviour. Results of experimental tests are presented to validate its performance. A comparison to other hydraulic actuation systems is performed. The use of the proposed hydraulic flexible joint in adaptive robotic structures is addressed and discussed.

High Precision Hydrostatic Actuation Systems for Micro- and Nanomanipulation of Heavy Loads

2005 ◽  
Vol 128 (4) ◽  
pp. 778-787 ◽  
Author(s):  
Saeid Habibi ◽  
Richard Burton ◽  
Eric Sampson
Keyword(s):  
High Precision ◽  
Experimental Results ◽  
Positional Accuracy ◽  
Large Load ◽  
Actuation System ◽  
Heavy Loads ◽  
Actuation Systems ◽  
Laboratory Prototype ◽  
Electrohydraulic Actuator

In this paper reports on an important finding, that is, hydrostatic actuation systems are able to manipulate heavy loads with submicron precision and a large stroke. In this relation, the design of a high-precision hydrostatic actuation system referred to as the ElectroHydraulic Actuator (EHA) is presented. A laboratory prototype of this system has achieved an unprecedented level of performance by being able to move a large load of 20Kg with a precision of 100nm and a stroke of 12cm. This level of performance places the hydrostatic actuation concept in competition with piezoelectric platforms in terms of positional accuracy. Experimental results from this prototype are reported and analyzed.

The Applicability of Electrically Driven Accessories for Turboshaft Engines

1995 ◽  
Vol 117 (2) ◽  
pp. 221-226
Author(s):  
M. S. Jarvis ◽  
W. J. Ostergren ◽  
B. Smith
Keyword(s):  
Electrical Power ◽  
Particle Separation ◽  
Control Unit ◽  
Propulsion Systems ◽  
Switched Reluctance ◽  
Actuation System ◽  
Switched Reluctance Machines ◽  
Starter Generator ◽  
Actuation Systems ◽  
Variable Stator

Improved electrical power generation and actuation systems offer new design approaches for performing the engine control and accessory functions in helicopter propulsion systems. Present helicopter technology utilizes turboshaft engines with mechanically driven accessories. These accessories perform the functions of starting, fuel and lube pumping, variable stator actuation, and inlet particle separation. This paper discusses the applicability of replacing the mechanically driven accessories with their electrically driven counterparts. An electric accessory system is defined, which includes a switched reluctance starter/generator and its associated control unit; an electric pumping and actuation system; and the engine mounting for the starter/generator. A comparison between the mechanically and electrically driven accessory systems is performed on the basis of cost, weight, and reliability. Experience to date with switched reluctance machines and electrically driven turbo shaft accessory systems is summarized. The benefits of electrically driven accessories are shown and recommendations for future activity for his important technology are discussed.

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