????????? ????????? ????????? ???????????? ????????? ?????? ?????? ??? ?????? ??????

Department of Mechanical EngineeringThe potential danger of invisible hazardous substance leakage accident is increasing, such as hazardous chemical leakage accidents in industrial complexes, potential risks of aging nuclear power plants, and international chemical terrorism threats. In particular, hazardous chemical, biological, or radioactive substances leaked into the atmosphere cause irreversible damage to nature, and there is a risk of human damage if prompt action is not taken. Therefore, estimating the emission source and the amount of invisible hazardous substances is required to minimize human casualties and increase public safety. As the risk of hazardous material leakage and potential terrorism increases in random places, it is difficult using traditional systems such as pre-installed ground sensors in a specific area. This thesis proposes autonomous search method for estimating the source of hazardous materials using a mobile sensor attached to an unmanned aerial vehicle (UAV). Since the mobile sensor can be freely deployed to any arbitrary places, it is possible to monitor a wider area with a relatively low cost. Besides, this approach is an unmanned autonomous system, so it has the advantage of minimizing secondary human casualties that may additionally occur during search. The source term estimation (STE) using mobile sensors is considered to be a challenging problem because the sensor measurements from atmospheric gas dispersion are sparse, intermittent, and time-varying due to the turbulence and the sensor noise. Thus, Bayesian inference-based estimation technique, sequential Monte Carlo method (i.e., particle filter), is used to estimate the source by using the inaccurate measurements which is easily influenced by air turbulence and sensor noise in this thesis. The autonomous search algorithms using information theory are also proposed. In the proposed algorithms, the information entropy (i.e., uncertainty of estimation) is calculated by using information theory and the agent choose the action to move to the next sensing location that can minimize the expected uncertainty. In other words, the proposed information-theoretic search algorithm is reward-based decision making approaches that use information entropy as a reward. The receding horizon and Gaussian mixture model clustering approaches are adopted to improve the search performance in various environment. Since the time required to compute all of the respective rewards increases as the number of action candidates increases, the policy-based autonomous source term search and estimation algorithm is proposed using deep neural network and reinforcement learning approach to determine efficient search path considering continuous action space. Furthermore, this thesis proposes a cooperative search method for multiple unmanned mobile vehicles based on game theory. The inaccuracy of sensor measurement values can be reduced by using multiple mobile sensors with the fusion approach, so the source of hazardous substances can be quickly estimated. The negotiation based on the game theory can improve the group search performance for source term estimation and search. Finally, to verify the performance of the proposed algorithm, numerical simulation and flight test results using an actual gas measurement sensor and multicopter drone are presented.ope

Compensating for model uncertainty in the control of cooperative field robots

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2002.Includes bibliographical references (p. 113-123).Current control and planning algorithms are largely unsuitable for mobile robots in unstructured field environment due to uncertainties in the environment, task, robot models and sensors. A key problem is that it is often difficult to directly measure key information required for the control of interacting cooperative mobile robots. The objective of this research is to develop algorithms that can compensate for these uncertainties and limitations. The proposed approach is to develop physics-based information gathering models that fuse available sensor data with predictive models that can be used in lieu of missing sensory information. First, the dynamic parameters of the physical models of mobile field robots may not be well known. A new information-based performance metric for on-line dynamic parameter identification of a multi-body system is presented. The metric is used in an algorithm to optimally regulate the external excitation required by the dynamic system identification process. Next, an algorithm based on iterative sensor planning and sensor redundancy is presented to enable field robots to efficiently build 3D models of their environment. The algorithm uses the measured scene information to find new camera poses based on information content. Next, an algorithm is presented to enable field robots to efficiently position their cameras with respect to the task/target. The algorithm uses the environment model, the task/target model, the measured scene information and camera models to find optimum camera poses for vision guided tasks. Finally, the above algorithms are combined to compensate for uncertainties in the environment, task, robot models and sensors. This is applied to a cooperative robot assembly task in an unstructured environment.(cont.) Simulations and experimental results are presented that demonstrate the effectiveness of the above algorithms on a cooperative robot test-bed.by Vivek Anand Sujan.Ph.D

Manipulador aéreo con brazos antropomórficos de articulaciones flexibles

[Resumen] Este artículo presenta el primer robot manipulador aéreo con dos brazos antropomórficos diseñado para aplicarse en tareas de inspección y mantenimiento en entornos industriales de difícil acceso para operarios humanos. El robot consiste en una plataforma aérea multirrotor equipada con dos brazos antropomórficos ultraligeros, así como el sistema de control integrado de la plataforma y los brazos. Una de las principales características del manipulador es la flexibilidad mecánica proporcionada en todas las articulaciones, lo que aumenta la seguridad en las interacciones físicas con el entorno y la protección del propio robot. Para ello se ha introducido un compacto y simple mecanismo de transmisión por muelle entre el eje del servo y el enlace de salida. La estructura en aluminio de los brazos ha sido cuidadosamente diseñada de forma que los actuadores estén aislados frente a cargas radiales y axiales que los puedan dañar. El manipulador desarrollado ha sido validado a través de experimentos en base fija y en pruebas de vuelo en exteriores.Ministerio de Economía y Competitividad; DPI2014-5983-C2-1-

La philosophie naturelle d'Aristote et le problème contemporain de l'inscription corporelle de l'esprit

En raison du progrès soutenu des sciences expérimentales et des technologies de l’information, plusieurs chercheurs en neurosciences affirment que nous sommes plus près que jamais de montrer la façon dont la physiologie et l’organisation du cerveau produisent les fonctions supérieures du système nerveux. Ainsi, des scientifiques de renom ont commencé à formuler des hypothèses, à construire des théories et à développer des modèles de simulation numérique en vue d’expliquer l’apparition de la conscience à partir des mécanismes de signalisation neuronale et de la modification adaptative des circuits nerveux cérébraux. Les philosophes aussi cherchent maintenant à formuler la solution au problème de l’explication de l’unité du corps et de l’esprit sur les bases de ces connaissances. Mais étant donné que cette approche implique la compréhension des phénomènes mentaux en termes de phénomènes physiques, leur réflexion conduit, en général, soit à une description réductionniste de l’esprit, soit à un dualisme de propriétés. C’est pourquoi certains d’entre eux ont proposé récemment de chercher dans la philosophie naturelle d’Aristote la direction que devrait emprunter cette recherche. Pourtant, plusieurs des arguments avancés par ces savants contemporains à l’appui de leurs thèses comportent des erreurs de principe, de compréhension ou de méthode qui mettent sérieusement en doute la solidité de leurs propositions. Cette recherche analyse en détail ces arguments dans le dessein de faire ressortir les principales difficultés et de les enlever pour juger d’une façon plus éclairée de la vraie contribution de ces connaissances à notre compréhension de l’unité naturelle que forment le corps et l’esprit. Sa démarche se divise en trois étapes principales. La première vise à prendre connaissance de l’état actuel de la recherche expérimentale en neurobiologie, la deuxième évalue deux modèles représentatifs de la recherche théorique des neurosciences et la troisième se propose de parvenir à comprendre le plus exactement possible la façon dont Aristote rend compte de l’unité du corps et de l’esprit. Trois observations générales résultent de cet examen. Premièrement, qu’en réalité la neurobiologie ne cherche pas à comprendre l’aspect phénoménal des fonctions supérieures du cerveau, mais uniquement leurs fondements neuraux, car elle est consciente de ses limites naturelles en tant que science expérimentale. Deuxièmement, que les arguments avancés par ces modèles théoriques de la conscience en faveur de la compréhension biologique des fonctions supérieures du système nerveux se servent principalement de l’altération du sens des mots du vocabulaire associé à la cognition pour accomplir le passage des phénomènes biologiques aux phénomènes mentaux, proposant essentiellement de comprendre ces derniers comme le résultat d’une inférence statistique accomplie par la signalisation neuronale grâce à la structuration adaptative des circuits nerveux. Troisièmement, que la philosophie naturelle d’Aristote accomplit réellement l’unité du corps et de l’esprit, mais qu’elle ne parvient pas à expliquer cette unité à partir des mécanismes de la perception et du mouvement de l’animal, mais plutôt à partir des principes qui fondent son étude de la nature, et que les objections formulées à ses arguments découlent d’une lecture fragmentaire ou biaisée de ses écrits et d’une compréhension superficielle ou erronée de ses concepts fondamentaux de sa philosophie. Ces observations permettent de conclure que la tâche de la philosophie de la nature n’est pas celle d’accommoder sa réflexion concernant l’unité que forment ensemble le corps, l’âme et l’esprit aux résultats des sciences expérimentales, mais celle de formuler des principes aptes à unifier les différents aspects de la réalité sur lesquels portent ces différentes sciences.The steady progress of experimental science and information technologies has led several researchers in the neurosciences to affirm that we are now closer than ever to disclosing the way in which the physiological organisation of the brain produces the higher functions of the nervous system. Consequently, these renowned scientists have proposed hypotheses, elaborated theories and developed numerical simulation models in order to explain the emergence of consciousness from the mechanics of neural signaling and the adaptation of the brain’s neural circuits. Philosophers are currently also seeking the solution to the problem of explaining the unity of body and mind on the basis of this knowledge. But as this approach implies describing mental phenomena in terms of the underlying physical phenomena, their reflections generally lead either to a reductionist description of the mind or to a dualist theory. For this reason, certain of them have recently proposed that such research should look for inspiration in the natural philosophy of Aristotle. However, several of the arguments advanced by these contemporary researchers in the support of their theses are flawed by errors of principle, of comprehension or of method, which place serious doubt upon the solidity of their propositions. In the present dissertation these arguments are placed under detailed scrutiny in order to pinpoint the main difficulties and discard them, allowing a clearer evaluation of the true contribution of these propositions to our understanding of the natural unity formed by body and the mind. This project is divided into three major sections. The first is intended to present the current state of experimental research in neurobiology; the second evaluates two representative models from current theoretical research in neuroscience; and the third endeavours to come to as exact an understanding as possible of the way in which Aristotle treats the unity of the body and the soul, to which the intellect v i belongs in the particular case of man and whose concept does not exactly match the contemporary concept of mind. There are three general observations that can be drawn from this examination. Firstly, in reality neurobiology does not seek to explain the phenomenal aspects of the brain’s higher functions, only their neurological bases, because as an experimental science it is bound by natural limits. Secondly, the arguments put forth by theoretical models of consciousness in favour of a biological understanding of the higher neurological functions are mainly based on the alteration of the meaning of words associated with cognition in order to make the transition from biological to mental phenomena. These phenomena would then be understood essentially as the result of statistical inference accomplished by neuronal signaling, made possible by the adaptive restructuring of neural circuits. Thirdly, Aristotle’s natural philosophy truly succeeds in uniting body and soul, but his explanation of this unity is not founded on the mechanisms of perception and movement in the animal, but rather on the principles underlying his study of nature, and the objections that have been raised against his arguments have been based on fragmentary or biased readings of his writings, and on an erroneous or superficial understanding of the fundamental concepts of his philosophy. These observations allow us to draw the conclusion that the proper task of the philosophy of nature is not to accommodate its reflections concerning the unity of body, soul and spirit to the results of experimental science, but rather that of formulating the principles that unify the different aspects of reality upon which the different sciences are based

Integrative (Synchronisations-)Mechanismen der (Neuro-)Kognition vor dem Hintergrund des (Neo-)Konnektionismus, der Theorie der nichtlinearen dynamischen Systeme, der Informationstheorie und des Selbstorganisationsparadigmas

Der Gegenstand der vorliegenden Arbeit besteht darin, aufbauend auf dem (Haupt-)Thema, der Darlegung und Untersuchung der Lösung des Bindungsproblems anhand von temporalen integrativen (Synchronisations-)Mechanismen im Rahmen der kognitiven (Neuro-)Architekturen im (Neo-)Konnektionismus mit Bezug auf die Wahrnehmungs- und Sprachkognition, vor allem mit Bezug auf die dabei auftretende Kompositionalitäts- und Systematizitätsproblematik, die Konstruktion einer noch zu entwickelnden integrativen Theorie der (Neuro-)Kognition zu skizzie-ren, auf der Basis des Repräsentationsformats einer sog. „vektoriellen Form“, u.z. vor dem Hintergrund des (Neo-)Konnektionismus, der Theorie der nichtlinearen dynamischen Systeme, der Informationstheorie und des Selbstorganisations-Paradigmas