4,592 research outputs found
Neuro-fuzzy modeling of multi-field surface neuroprostheses for hand grasp
154 p.Las neuroprótesis aplican pulsos eléctricos a los nervios periféricos con el objetivo de sustituir funciones motrices/sensoriales perdidas, dando asistencia e influyendo positivamente en la rehabilitación motriz de personas con disfunciones motrices causadas por trastornos neurológicos. La complejidad de la neuroanatomía del antebrazo y la mano, su dimensionalidad, las diversas tareas no-cíclicas, la variabilidad de movimientos entre sujetos y la reducida selectividad de las neuroprótesis superficiales, ha dado lugar al diseño de un número reducido de neuroprótesis orientadas a agarres básicos. La posibilidad de hacer más selectiva la estimulación mediante los electrodos multi-campo, junto con el conocimiento sobre la incomodidad y los movimientos que genera la aplicación de la estimulación eléctrica funcional (FES por sus siglas en inglés) en miembro superior, podrían ser base fundamental para el desarrollo de neuroprótesis de agarre más avanzadas. La presente tesis describe un análisis de incomodidad como resultado de FES en el miembro superior, y propone modelos neuro-difusos para neuroprótesis de agarre tanto para personas sanas como para personas con trastornos neurológicos. El conocimiento generado respecto a la incomodidad puede ser utilizado como guía para desarrollar aplicaciones de FES de miembro superior más cómodas. Del mismo modo, los modelos propuestos en esta tesis pueden ser utilizados para apoyar el diseño y la validación de sistemas de control avanzados en neuroprótesis dirigidas a la función de agarre.Tecnalia; Intelligent Control Research Grou
Torque Control
This book is the result of inspirations and contributions from many researchers, a collection of 9 works, which are, in majority, focalised around the Direct Torque Control and may be comprised of three sections: different techniques for the control of asynchronous motors and double feed or double star induction machines, oriented approach of recent developments relating to the control of the Permanent Magnet Synchronous Motors, and special controller design and torque control of switched reluctance machine
Advances in power quality analysis techniques for electrical machines and drives: a review
The electric machines are the elements most used at an industry level, and they represent the major power consumption of the productive processes. Particularly speaking, among all electric machines, the motors and their drives play a key role since they literally allow the motion interchange in the industrial processes; it could be said that they are the medullar column for moving the rest of the mechanical parts. Hence, their proper operation must be guaranteed in order to raise, as much as possible, their efficiency, and, as consequence, bring out the economic benefits. This review presents a general overview of the reported works that address the efficiency topic in motors and drives and in the power quality of the electric grid. This study speaks about the relationship existing between the motors and drives that induces electric disturbances into the grid, affecting its power quality, and also how these power disturbances present in the electrical network adversely affect, in turn, the motors and drives. In addition, the reported techniques that tackle the detection, classification, and mitigations of power quality disturbances are discussed. Additionally, several works are reviewed in order to present the panorama that show the evolution and advances in the techniques and tendencies in both senses: motors and drives affecting the power source quality and the power quality disturbances affecting the efficiency of motors and drives. A discussion of trends in techniques and future work about power quality analysis from the motors and drives efficiency viewpoint is provided. Finally, some prompts are made about alternative methods that could help in overcome the gaps until now detected in the reported approaches referring to the detection, classification and mitigation of power disturbances with views toward the improvement of the efficiency of motors and drives.Peer ReviewedPostprint (published version
An investigation into motor pools and their applicability to a biologically inspired model of ballistic voluntary motor action
This study investigates the properties of motor pools in the human motor control
system. The simulations carried out as part of this study used two biologically
inspired neuronal models to simulate networks with properties similar to those
observed in the human motor system (Burke, 1991). The Synchronous neuronal
model developed as part of this study explicitly models the input/output spike train
and frequency relationship of each neuron. The motor pool simulations were carried
out using the INSIGHT TOO simulation software developed as part of this study.
INSIGHT TOO is a flexible neural design tool that allows the visual interactive
design of network connectivity and has the power of a node specification language
similar to that of BASIC that allows multi-layer, multi-model networks to be
simulated. The simulations have shown that the motor pools are capable of
reproducing commonly observed physiological properties during normal voluntary
reaching movements. As a result of these findings a theoretical model of ballistic
voluntary motor action was proposed called the Recruitment Model.
The Recruitment model utilises the "recruitment" principle known to exist in motor
pools and applies this distributed processing methodology to the higher levels of
motor action to explain how complex structures similar to the human skeletal
system might be controlled. A simple version of the Recruitment Model is simulated
showing an animation of a running "stick man". This simulation demonstrates some
of the principles necessary to solve problems relating to synergy formation
Bridging the gap between emotion and joint action
Our daily human life is filled with a myriad of joint action moments, be it children playing, adults working together (i.e., team sports), or strangers navigating through a crowd. Joint action brings individuals (and embodiment of their emotions) together, in space and in time. Yet little is known about how individual emotions propagate through embodied presence in a group, and how joint action changes individual emotion. In fact, the multi-agent component is largely missing from neuroscience-based approaches to emotion, and reversely joint action research has not found a way yet to include emotion as one of the key parameters to model socio-motor interaction. In this review, we first identify the gap and then stockpile evidence showing strong entanglement between emotion and acting together from various branches of sciences. We propose an integrative approach to bridge the gap, highlight five research avenues to do so in behavioral neuroscience and digital sciences, and address some of the key challenges in the area faced by modern societies
Control Theory in Engineering
The subject matter of this book ranges from new control design methods to control theory applications in electrical and mechanical engineering and computers. The book covers certain aspects of control theory, including new methodologies, techniques, and applications. It promotes control theory in practical applications of these engineering domains and shows the way to disseminate researchers’ contributions in the field. This project presents applications that improve the properties and performance of control systems in analysis and design using a higher technical level of scientific attainment. The authors have included worked examples and case studies resulting from their research in the field. Readers will benefit from new solutions and answers to questions related to the emerging realm of control theory in engineering applications and its implementation
Identification and development of microgrids emergency control procedures
Tese de doutoramento. Engenharia Electrotécnica e de Computadores. Faculdade de Engenharia. Universidade do Porto. 200
A Review of Control Techniques for Wind Energy Conversion System
Wind energy is the most efficient and advanced form of renewable energy (RE) in recent decades, and an effective controller is required to regulate the power generated by wind energy. This study provides an overview of state-of-the-art control strategies for wind energy conversion systems (WECS). Studies on the pitch angle controller, the maximum power point tracking (MPPT) controller, the machine side controller (MSC), and the grid side controller (GSC) are reviewed and discussed. Related works are analyzed, including evolution, software used, input and output parameters, specifications, merits, and limitations of different control techniques. The analysis shows that better performance can be obtained by the adaptive and soft-computing based pitch angle controller and MPPT controller, the field-oriented control for MSC, and the voltage-oriented control for GSC. This study provides an appropriate benchmark for further wind energy research
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