Electromagnetic Problems Taking into Account External Power Sources

1989 ◽  
pp. 47-77
Author(s):  
M. Enokizono
Keyword(s):  
Power Sources ◽  
Electromagnetic Problems ◽  
External Power

scholarly journals Active plantar-flexion above-knee prosthesis: Concept and preliminary design

1985 ◽  
Vol 9 (3) ◽  
pp. 141-144 ◽  
Author(s):  
C. Rigas
Keyword(s):  
Lower Limb ◽  
Knee Prosthesis ◽  
Plantar Flexion ◽  
High Mass ◽  
Energy Output ◽  
Promising Alternative ◽  
Power Sources ◽  
Ankle Joints ◽  
External Power ◽  
Lower Limb Prostheses

Lower limb prostheses produced so far do not replace the function of the musculature, which provides the necessary amount and the proper distribution of energy to the ambulatory mechanism. Provision of external power to lower limb prostheses has been hindered by the fact that the large amount of energy needed at a lower limb necessitates the use of external power sources of unacceptably high mass and volume. Self energized mechanisms offer a promising alternative to the problem. Normally a large part of energy output during locomotion appears at the ankle joint. It seems therefore desirable to develop an above-knee prosthesis featuring active plantar-flexion at the ankle. Energy may be offered by a self energized system. The system, described here, accumulates energy during the passive movements of the knee and ankle joints and stores it for later use at the ankle.

scholarly journals Multifunctional above-knee prosthesis for stairs' walking

1987 ◽  
Vol 11 (3) ◽  
pp. 139-145 ◽  
Author(s):  
K. Koganezawa ◽  
H. Fujimoto ◽  
I. Kato
Keyword(s):  
Knee Joint ◽  
Ankle Joint ◽  
Stance Phase ◽  
Knee Prosthesis ◽  
Power Sources ◽  
Stair Ascent ◽  
Level Walking ◽  
External Power ◽  
Leg Prosthesis ◽  
Full Body

The multifunctional above-knee prosthesis WLP-7R (Waseda Leg Prosthesis - type 7 Refined) described in this study allows amputees to descend and ascend stairs with no external power sources. With the hydraulic circuit mounted in the shank, the ankle joint and the knee joint mutually conterbalance during stance phase in stair walking as well as level walking so that the following performances are obtained. The yielding (flexing) of the knee joint is prevented and smooth advance from stance-phase to swing-phase is realized in level walking. The gradual yielding of the knee joint and the ankle joint while sustaining full body weight is realized in stair descent. Reciprocal stepping with sound and disabled legs during stair ascent is also realised although the powerful extension of the knee joint during stance phase is not possible. The performance of the WLP-7R was examined by a walking experiment in which amputees could descend and ascend the stairs as well as walk on a flat surface after approximately one hour's training.

Design and Control of a Pneumatically Actuated Lower-Extremity Orthosis

2012 ◽  
Vol 6 (4) ◽  
Author(s):  
Sai-Kit Wu ◽  
Tad Driver ◽  
Xiangrong Shen
Keyword(s):  
Lower Extremity ◽  
High Power Density ◽  
Mechanical Device ◽  
Natural Interaction ◽  
Joint Power ◽  
Power Sources ◽  
Pneumatic Actuators ◽  
Finite State ◽  
External Power ◽  
And Control

Lower-extremity orthosis is a type of wearable mechanical device that serves a wide variety of important biomedical purposes, such as gait assistance and rehabilitative training. Due primarily to the constraints associated with actuation technology, the majority of current lower-extremity orthoses are either passive or tethered to external power sources, limiting the functionality of such devices. In this paper, the authors present the research results towards a fully mobile (i.e., untethered) powered lower-limb orthosis, leveraging the high power density of pneumatic actuators for the joint power generation. The design of the orthosis is presented, with the objectives of providing full locomotive assistance in multiple common locomotive modes and generating a minimum level of restriction to the wearer's daily activities. For the control of the orthosis, a finite-state impedance-based controller is developed, which simulates an artificial impedance in order to enable the natural interaction with the wearer. Preliminary testing on a healthy subject demonstrated that the orthosis was able to provide a natural gait and a comfortable user experience in the treadmill walking experiments.

scholarly journals Accounting power supply schemes for traction substations in the calculation of short circuits in the AC traction network

2019 ◽  
Vol 78 (1) ◽  
pp. 10-18 ◽  
Author(s):  
Yu. I. Zharkov ◽  
N. A. Popova ◽  
E. P. Figurnov
Keyword(s):  
High Voltage ◽  
Power Supply ◽  
Power Supply System ◽  
Short Circuit ◽  
Supply System ◽  
Power Sources ◽  
Traction Network ◽  
Traction Substations ◽  
External Power ◽  
External Power Supply

When calculating short-circuit currents in the AC traction network, it is assumed that each of the traction substations receives power from uncoupled external power supply sources with known resistances. In some cases, especially when powering a group of traction substations from a high-voltage power line of a longitudinal power supply, the external power supply system affects not only the magnitude of short-circuit currents, but also their redistribution between adjacent traction substations of the interstation area where this circuit is considered. Such unrecorded redistribution can have a negative effect on short circuit protection. The article considers the equivalent circuit of the traction network, taking into account resistance of the external power supply system. Particular attention is paid to the fact that in replacement circuits of direct and negative sequence value of reduced resistance of one phase of a multiwinding transformer, calculated from the short circuit voltage, does not depend on the connection scheme of its windings. It is noted that in some cases it is difficult to obtain a complete scheme of an external power supply system. Considering that the short circuit in the traction network for the external power supply system is remote, it is proposed taking into account the reference network or traction substations as power sources, from which high-voltage transmission lines power the traction substations. Resistance of the supporting substations as power sources must takes into account connected equivalent power system.Such equivalenting should be carried out by known values of currents or short-circuit powers at the inputs of the reference substation or, if such information is not available, by the rated values of the switched-off currents or powers of the switches of high-voltage line connections.The following power schemes for traction substations are considered: each from its own supporting substation, which is part of an electrically uncoupled external power supply system; from the double-circuit high-voltage line of longitudinal power supply when it is powered from different supporting substations; from the supporting network substation, the traction substation receives power from two lines, and from this the traction substations receive power from two lines in a circle pattern.These three common cases cover all the most common power schemes for traction substations. For each of them formulas are given to determine the resulting equivalent resistance of the external power supply circuit, which should be taken into account in the replacement circuit of the traction network.

scholarly journals Comparison and adaptation of operating modes of a mobile charger for electric vehicles

2021 ◽  
Vol 79 (5) ◽  
pp. 146-147
Author(s):  
G.M. Ryazapov ◽  
Y.V. Zhukova
Keyword(s):  
Electric Vehicles ◽  
Voltage Versus ◽  
Power Sources ◽  
Operating Modes ◽  
Advantages And Disadvantages ◽  
Charge Current ◽  
Current Curve ◽  
External Power ◽  
Mobile Charger

The article deals with the operating modes of a mobile charger for electric vehicles and their external power sources adaptation. Mains voltage-versus-charge current curve is given. Besides, the authors of the article consider important advantages and disadvantages of the charger operating modes.

scholarly journals Magnetorheological Elastomer-Based Self-Powered Triboelectric Nanosensor for Monitoring Magnetic Field

Nanomaterials ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 2815
Author(s):  
Dong Wan ◽  
Ningchen Ma ◽  
Taochuang Zhao ◽  
Xiaojing Cui ◽  
Zhaosu Wang ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Fast Response ◽  
Magnetic Sensor ◽  
Triboelectric Nanogenerator ◽  
Magnetorheological Elastomer ◽  
Field Range ◽  
Power Sources ◽  
Electrostatic Induction ◽  
External Power ◽  
Self Powered

The adaptable monitoring of the ubiquitous magnetic field is of great importance not only for scientific research but also for industrial production. However, the current detecting techniques are unwieldly and lack essential mobility owing to the complex configuration and indispensability of the power source. Here, we have constructed a self-powered magnetic sensor based on a subtle triboelectric nanogenerator (TENG) that consists of a magnetorheological elastomer (MRE). This magnetic sensor relies on triboelectrification and electrostatic induction to produce electrical signals in response to the MRE’s deformation induced by the variational magnetic field without using any external power sources. The fabricated magnetic sensor shows a fast response of 80ms and a desirable sensitivity of 31.6 mV/mT in a magnetic field range of 35–60 mT as well as preliminary vectorability enabled by the multichannel layout. Our work provides a new route for monitoring dynamic magnetic fields and paves a way for self-powered electric-magnetic coupled applications.

scholarly journals Biodegradable triboelectric nanogenerator as a life-time designed implantable power source

2016 ◽  
Vol 2 (3) ◽  
pp. e1501478 ◽  
Author(s):  
Qiang Zheng ◽  
Yang Zou ◽  
Yalan Zhang ◽  
Zhuo Liu ◽  
Bojing Shi ◽  
...  
Keyword(s):  
Life Time ◽  
Power Source ◽  
Inorganic Materials ◽  
Triboelectric Nanogenerator ◽  
Long Term Effects ◽  
Power Sources ◽  
Work Cycle ◽  
External Power ◽  
Pulsed Electrical Field

Transient electronics built with degradable organic and inorganic materials is an emerging area and has shown great potential for in vivo sensors and therapeutic devices. However, most of these devices require external power sources to function, which may limit their applications for in vivo cases. We report a biodegradable triboelectric nanogenerator (BD-TENG) for in vivo biomechanical energy harvesting, which can be degraded and resorbed in an animal body after completing its work cycle without any adverse long-term effects. Tunable electrical output capabilities and degradation features were achieved by fabricated BD-TENG using different materials. When applying BD-TENG to power two complementary micrograting electrodes, a DC-pulsed electrical field was generated, and the nerve cell growth was successfully orientated, showing its feasibility for neuron-repairing process. Our work demonstrates the potential of BD-TENG as a power source for transient medical devices.

The Role of Rechargeable Systems in Neuromodulation

2011 ◽  
Vol 6 (3) ◽  
pp. 187 ◽  
Author(s):  
Paul Eldridge ◽  
Brian Simpson ◽  
James Gilbart ◽  
◽  
◽  
...  
Keyword(s):  
Neuropathic Pain ◽  
Electronic Device ◽  
Electrical Power ◽  
Skin Surface ◽  
Battery Life ◽  
Power Sources ◽  
Pulse Generators ◽  
Repeated Surgery ◽  
External Power ◽  
Varied System

Neuromodulation is an effective treatment for many types of neuropathic pain but a significant limitation of any neuromodulating system is that electrical power must be conveyed in a reliable and sterile way to an implanted electronic device and transmitted to its associated electrodes. In recent decades radio-frequency-coupled devices and internal pulse generators have been developed. These were significant advances but were limited either by the need for bulky external power sources or the need for surgery at intervals to replace the internal system battery. More recently, rechargeable neuromodulatory systems have become available. These considerably improve patient convenience and mobility. After surgical implantation, the system can be charged from an antenna placed at the skin surface, avoiding the need for repeated surgery, external equipment or wires penetrating the skin. Charging can be completed within a few hours and can last for up to one month, depending on use. Battery life is up to 25 years, depending on the manufacturer. Varied system programmability and availability of high power output make rechargeable systems applicable to a range of different neurological conditions and will make these systems a valuable approach to controlling chronic neuropathic pain.

scholarly journals Acondicionamiento Pasivo de una Vivienda en la Sierra de Madrid = Passive Conditioning of a Building in Sierra of Madrid

2015 ◽  
Vol 1 (1) ◽  
pp. 7 ◽  
Author(s):  
Carlos Morón ◽  
Alfonso García ◽  
Daniel Ferrández ◽  
Kenzo Hosokawa
Keyword(s):  
Energy Saving ◽  
Building Code ◽  
External Energy ◽  
Power Sources ◽  
Improve Efficiency ◽  
Current State ◽  
External Power ◽  
Rehabilitation Measures ◽  
Continental Climate

En el presente trabajo se analiza una posible solución para la rehabilitación energética de edificios situados en la Sierra de Madrid con un clima continental. Para la realización del mismo se escogió una vivienda construida en el año 1986 siguiendo las pautas de la ya derogada NTE-79. Su falta de intervención durante casi treinta años ha permitido realizar una simulación entre el estado actual y el estado posterior de la vivienda, tras haber tomado diferentes medidas de rehabilitación calificadas como pasivas, ya que no incluyen mecanismos ni dispositivos que requieran de alguna fuente alimentación externa más allá de la que nos permite el entorno en el cual se encuentra ubicado nuestro edificio. Se pretende demostrar que el empleo de soluciones de rehabilitación que no requieran de un consumo de energía externo, también pueden servir para mejorar la calificación energética de las viviendas actuales de manera más económica y que permita alcanzar el horizonte 2020 europeo para la mejora de la eficiencia energética. Las soluciones propuestas en este documento han ido encaminadas a cumplir con el actual Código Técnico de la Edificación, en su apartado de Ahorro de Energía recientemente modificado CTE-DB HE. Al final, se representan los resultados con la mejora en la calificación obtenida tras la puesta a punto de las medidas simuladas.  AbstractIn this work a possible solution to the energy rehabilitation of buildings located in Sierra of Madrid, with a continental climate, is analyzed. To execute this study, a 1986 building was chosen following the NTE-79 (which is currently repealed) guidelines. Its lack of intervention for nearly 30 years lets us make a simulation between the current state of the building and the subsequent one. The simulation was done after having taking different rehabilitation measures, classified as passives, because they do not include mechanisms or devices that required any external power sources beyond the ones that the environment, where our building is located, offer to us. It is pretended to demonstrate that the use of rehabilitation solutions do not required an external energy consume. It can also improve the energy rating of current building more cheaply, and allows reaching the European 2020 goal to improve efficiency energy. The suggested solutions we have described in this paper have been conducted to comply with the technical building code, specifically with its recently modified section, CTE-DB HE Energy Saving Section. Finally, the results are represented including the rating improvement after the development of the simulated measurements.    

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