141 research outputs found

    Visual Servoing in Robotics

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    Visual servoing is a well-known approach to guide robots using visual information. Image processing, robotics, and control theory are combined in order to control the motion of a robot depending on the visual information extracted from the images captured by one or several cameras. With respect to vision issues, a number of issues are currently being addressed by ongoing research, such as the use of different types of image features (or different types of cameras such as RGBD cameras), image processing at high velocity, and convergence properties. As shown in this book, the use of new control schemes allows the system to behave more robustly, efficiently, or compliantly, with fewer delays. Related issues such as optimal and robust approaches, direct control, path tracking, or sensor fusion are also addressed. Additionally, we can currently find visual servoing systems being applied in a number of different domains. This book considers various aspects of visual servoing systems, such as the design of new strategies for their application to parallel robots, mobile manipulators, teleoperation, and the application of this type of control system in new areas

    Intuitive Instruction of Industrial Robots : A Knowledge-Based Approach

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    With more advanced manufacturing technologies, small and medium sized enterprises can compete with low-wage labor by providing customized and high quality products. For small production series, robotic systems can provide a cost-effective solution. However, for robots to be able to perform on par with human workers in manufacturing industries, they must become flexible and autonomous in their task execution and swift and easy to instruct. This will enable small businesses with short production series or highly customized products to use robot coworkers without consulting expert robot programmers. The objective of this thesis is to explore programming solutions that can reduce the programming effort of sensor-controlled robot tasks. The robot motions are expressed using constraints, and multiple of simple constrained motions can be combined into a robot skill. The skill can be stored in a knowledge base together with a semantic description, which enables reuse and reasoning. The main contributions of the thesis are 1) development of ontologies for knowledge about robot devices and skills, 2) a user interface that provides simple programming of dual-arm skills for non-experts and experts, 3) a programming interface for task descriptions in unstructured natural language in a user-specified vocabulary and 4) an implementation where low-level code is generated from the high-level descriptions. The resulting system greatly reduces the number of parameters exposed to the user, is simple to use for non-experts and reduces the programming time for experts by 80%. The representation is described on a semantic level, which means that the same skill can be used on different robot platforms. The research is presented in seven papers, the first describing the knowledge representation and the second the knowledge-based architecture that enables skill sharing between robots. The third paper presents the translation from high-level instructions to low-level code for force-controlled motions. The two following papers evaluate the simplified programming prototype for non-expert and expert users. The last two present how program statements are extracted from unstructured natural language descriptions

    Medical robots with potential applications in participatory and opportunistic remote sensing: A review

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    Among numerous applications of medical robotics, this paper concentrates on the design, optimal use and maintenance of the related technologies in the context of healthcare, rehabilitation and assistive robotics, and provides a comprehensive review of the latest advancements in the foregoing field of science and technology, while extensively dealing with the possible applications of participatory and opportunistic mobile sensing in the aforementioned domains. The main motivation for the latter choice is the variety of such applications in the settings having partial contributions to functionalities such as artery, radiosurgery, neurosurgery and vascular intervention. From a broad perspective, the aforementioned applications can be realized via various strategies and devices benefiting from detachable drives, intelligent robots, human-centric sensing and computing, miniature and micro-robots. Throughout the paper tens of subjects, including sensor-fusion, kinematic, dynamic and 3D tissue models are discussed based on the existing literature on the state-of-the-art technologies. In addition, from a managerial perspective, topics such as safety monitoring, security, privacy and evolutionary optimization of the operational efficiency are reviewed

    Nature-inspired algorithms for solving some hard numerical problems

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    Optimisation is a branch of mathematics that was developed to find the optimal solutions, among all the possible ones, for a given problem. Applications of optimisation techniques are currently employed in engineering, computing, and industrial problems. Therefore, optimisation is a very active research area, leading to the publication of a large number of methods to solve specific problems to its optimality. This dissertation focuses on the adaptation of two nature inspired algorithms that, based on optimisation techniques, are able to compute approximations for zeros of polynomials and roots of non-linear equations and systems of non-linear equations. Although many iterative methods for finding all the roots of a given function already exist, they usually require: (a) repeated deflations, that can lead to very inaccurate results due to the problem of accumulating rounding errors, (b) good initial approximations to the roots for the algorithm converge, or (c) the computation of first or second order derivatives, which besides being computationally intensive, it is not always possible. The drawbacks previously mentioned served as motivation for the use of Particle Swarm Optimisation (PSO) and Artificial Neural Networks (ANNs) for root-finding, since they are known, respectively, for their ability to explore high-dimensional spaces (not requiring good initial approximations) and for their capability to model complex problems. Besides that, both methods do not need repeated deflations, nor derivative information. The algorithms were described throughout this document and tested using a test suite of hard numerical problems in science and engineering. Results, in turn, were compared with several results available on the literature and with the well-known Durand–Kerner method, depicting that both algorithms are effective to solve the numerical problems considered.A Optimização é um ramo da matemática desenvolvido para encontrar as soluções óptimas, de entre todas as possíveis, para um determinado problema. Actualmente, são várias as técnicas de optimização aplicadas a problemas de engenharia, de informática e da indústria. Dada a grande panóplia de aplicações, existem inúmeros trabalhos publicados que propõem métodos para resolver, de forma óptima, problemas específicos. Esta dissertação foca-se na adaptação de dois algoritmos inspirados na natureza que, tendo como base técnicas de optimização, são capazes de calcular aproximações para zeros de polinómios e raízes de equações não lineares e sistemas de equações não lineares. Embora já existam muitos métodos iterativos para encontrar todas as raízes ou zeros de uma função, eles usualmente exigem: (a) deflações repetidas, que podem levar a resultados muito inexactos, devido ao problema da acumulação de erros de arredondamento a cada iteração; (b) boas aproximações iniciais para as raízes para o algoritmo convergir, ou (c) o cálculo de derivadas de primeira ou de segunda ordem que, além de ser computacionalmente intensivo, para muitas funções é impossível de se calcular. Estas desvantagens motivaram o uso da Optimização por Enxame de Partículas (PSO) e de Redes Neurais Artificiais (RNAs) para o cálculo de raízes. Estas técnicas são conhecidas, respectivamente, pela sua capacidade de explorar espaços de dimensão superior (não exigindo boas aproximações iniciais) e pela sua capacidade de modelar problemas complexos. Além disto, tais técnicas não necessitam de deflações repetidas, nem do cálculo de derivadas. Ao longo deste documento, os algoritmos são descritos e testados, usando um conjunto de problemas numéricos com aplicações nas ciências e na engenharia. Os resultados foram comparados com outros disponíveis na literatura e com o método de Durand–Kerner, e sugerem que ambos os algoritmos são capazes de resolver os problemas numéricos considerados

    Decoding Digital Culture with Science Fiction: Hyper-Modernism, Hyperreality, and Posthumanism

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    How do digital media technologies affect society and our lives? Through the cultural theory hypotheses of hyper-modernism, hyperreality, and posthumanism, Alan N. Shapiro investigates the social impact of Virtual/Augmented Reality, AI, social media platforms, robots, and the Brain-Computer Interface. His examination of concepts of Jean Baudrillard and Katherine Hayles, as well as films such as Blade Runner 2049, Ghost in the Shell, Ex Machina, and the TV series Black Mirror, suggests that the boundary between science fiction narratives and the »real world« has become indistinct. Science-fictional thinking should be advanced as a principal mode of knowledge for grasping the world and digitalization

    Computational Methods for Medical and Cyber Security

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    Over the past decade, computational methods, including machine learning (ML) and deep learning (DL), have been exponentially growing in their development of solutions in various domains, especially medicine, cybersecurity, finance, and education. While these applications of machine learning algorithms have been proven beneficial in various fields, many shortcomings have also been highlighted, such as the lack of benchmark datasets, the inability to learn from small datasets, the cost of architecture, adversarial attacks, and imbalanced datasets. On the other hand, new and emerging algorithms, such as deep learning, one-shot learning, continuous learning, and generative adversarial networks, have successfully solved various tasks in these fields. Therefore, applying these new methods to life-critical missions is crucial, as is measuring these less-traditional algorithms' success when used in these fields

    Haptics: Science, Technology, Applications

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    This open access book constitutes the proceedings of the 12th International Conference on Human Haptic Sensing and Touch Enabled Computer Applications, EuroHaptics 2020, held in Leiden, The Netherlands, in September 2020. The 60 papers presented in this volume were carefully reviewed and selected from 111 submissions. The were organized in topical sections on haptic science, haptic technology, and haptic applications. This year's focus is on accessibility

    Kinematics and Robot Design II (KaRD2019) and III (KaRD2020)

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    This volume collects papers published in two Special Issues “Kinematics and Robot Design II, KaRD2019” (https://www.mdpi.com/journal/robotics/special_issues/KRD2019) and “Kinematics and Robot Design III, KaRD2020” (https://www.mdpi.com/journal/robotics/special_issues/KaRD2020), which are the second and third issues of the KaRD Special Issue series hosted by the open access journal robotics.The KaRD series is an open environment where researchers present their works and discuss all topics focused on the many aspects that involve kinematics in the design of robotic/automatic systems. It aims at being an established reference for researchers in the field as other serial international conferences/publications are. Even though the KaRD series publishes one Special Issue per year, all the received papers are peer-reviewed as soon as they are submitted and, if accepted, they are immediately published in MDPI Robotics. Kinematics is so intimately related to the design of robotic/automatic systems that the admitted topics of the KaRD series practically cover all the subjects normally present in well-established international conferences on “mechanisms and robotics”.KaRD2019 together with KaRD2020 received 22 papers and, after the peer-review process, accepted only 17 papers. The accepted papers cover problems related to theoretical/computational kinematics, to biomedical engineering and to other design/applicative aspects

    Mental and sensorimotor extrapolation fare better than motion extrapolation in the offset condition

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    Evidence for motion extrapolation at motion offset is scarce. In contrast, there is abundant evidence that subjects mentally extrapolate the future trajectory of weak motion signals at motion offset. Further, pointing movements overshoot at motion offset. We believe that mental and sensorimotor extrapolation is sufficient to solve the problem of perceptual latencies. Both present the advantage of being much more flexible than motion extrapolatio

    The philosophy of religion of Henri Bergson

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    Bergson's philosophy of religion is not to be understood apart from the philosophical insights and the conception of philosophic method developed in his earlier works, written more than twenty-five years before the publication of his book on morality and religion.Bergson believed that the work of any philosopher springs from a single fundamental insight, which he then repeats and develops in various ways. In his own case this fundamental insight is the apprehension of the distinction between time as measured and conceived and time as conscious lived duration. This is the theme of his earliest work, Time and Free Will, where the distinction leads Bergson to a denial that the concepts of the understanding can contain or account for the realities of consciousness or of movement and change. Consciousness cannot be described in terms of the succession of conscious states, and movement and change can only be apprehended by the same kind of intuition as that by which we are aware of conscious lived duration, in which the past is in some sense contained in the present.This central intuition of the enduring active self of consciousness is further developed in the study of memory and perception in Matter and Memory. The study of memory is central to the traditional problem of the union of body and mind, and leads to a conception of brain and body as the instruments by which mind and memory are limited, concentrated, and made present to the world.In various essays, and in the book Creative Evolution, the distinction between intelligence and intuition suggested by duration is worked out. The concepts and language of the intelligence can only apprehend a reality in terms of universale, or general ideas, an intuition is necessary to grasp a reality as it is in itself, by a kind of sympathy with it. All reality is continuity and change, and while the concepts of intelligence are necessary to thought and its expression, only intuition can grasp the real. This inability of intelligence to represent reality is illustrated in the study of the phenomena of life in Creative Evolution, which suggests a vision of reality as a whole as a manifestation of a vital creative impetus.Bergson's "vitalist" cosmology is suggested rather than worked out as a metaphysical system, and the thesis suggests that it is not necessary to interpret Bergson in a vitalist sense. The characteristics of life or the vital impetus are indicative of the activity of the knowing mind in apprehending the reality of life, and are a further characterization of the method of intuition.It is in the context of following out the implications of the "discovery" of duration and in the development of the method of intuition that the problem of ethics and religion arose for Bergson. This study is undertaken in order to complete his account of immediate experience by the examination of specifically human, social, experience, but the terms in which Bergson set himself the problem determine to a large extent the nature of his answer to it. His distinctions between closed and open morality and static and dynamic religion are valuable in showing the social realities which underlie moral obligation and religious rites and beliefs, and also in indicating the dynamic role of religion in social change. Bergson is less successful in his examination of religious experience as such, in which mysticism is given a central place. Mystical experience is interpreted as the fullest expression of the creative intuition of life, but in such a manner as to offer no clear criteria for distinguishing the object of religious experience from the world or life itself. Bergson does not distinguish between metaphysical intuition and specifically religious experience largely because of his failure to move beyond the organic categories of Creative Evolution to an appreciation of the nature of distinctively personal experience.Bergson's chief value for the philosophy of religion is in his method of description of immediate experience. His basic intuition of duration yields an insight into the nature of life and mind as essentially creative which is of permanent interest for epistemology and the interpretation of religion, and his distinction between intelligence and intuition emphasizes the role of imagination in metaphysical and theological statement
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