1,720,963 research outputs found
Comunicazione e Interazione per Robot Mobili: dal Laboratorio all'Industria
No full textComunicare e interagire con un robot sono compiti fondamentali per far sì che il robot agisca come desiderato sia in scenari di ricerca che industriali. In questa tesi, abbiamo sviluppato diversi metodi per interagire con i robot in molte applicazioni. La teleoperazione diretta consente all'utente di spostare direttamente il robot utilizzando un dispositivo per imporre il movimento del robot. Abbiamo studiato una nuova metodologia per consentire a un utente di teleoperare un sistema robotico in modo naturale. L'approccio proposto non richiede alcun dispositivo specifico ma si basa su oggetti di uso comune come uno smartwatch. Utilizzando questo approccio, è possibile interagire con un robot mobile in modo intuitivo spostando l'avambraccio dell'utente. La collaborazione uomo-robot è fondamentale quando si devono svolgere compiti cooperativi, come nel progetto TIREBOT. Il progetto TIREBOT consiste nella progettazione meccanica e nel controllo collaborativo di TIREBOT, un assistente robotico che aiuta gli operatori dell'officina nel processo di sostituzione delle ruote. L'operatore può interagire con il robot utilizzando un'interfaccia basata su gesti o tramite teleoperazione. Il robot capisce quando l'utente vuole collaborare e quando invece accade qualcosa di imprevisto. Nel primo scenario, l'utente è autorizzato ad avvicinarsi al robot. Nel secondo caso il robot deve allontanarsi dall'utente per mantenere la sicurezza. Le applicazioni industriali quali le attività agricole possono richiedere molto sforzo e causare una serie di lesioni e malattie, pertanto può essere utile lasciare che il robot faccia il duro lavoro. In questo campo, abbiamo sviluppato due diversi sistemi robotici. Il primo è un sistema autonomo a basso costo che può navigare attraverso un vigneto mentre raccoglie immagini di uva per fornire una stima della produzione. Il secondo sistema è un robot per la raccolta delle mele. Il robot può identificare le mele nella scena, avvicinarsi alla mela per afferrarla e staccarla dall'albero. Durante l'esecuzione dell'attività desiderata, l'essere umano non è l'unico agente con cui il robot deve interagire. Esso infatti deve interagire con altri robot per raggiungere l'obiettivo desiderato. Nei sistemi multi-robot le interconnessioni passive tra agenti vengono spesso sfruttate per ottenere un comportamento cooperativo desiderato stabile in modo robusto. Noi sfruttiamo il concetto di energy tank per costruire una nuova interconnessione generalizzata che consenta di imporre qualsiasi tipo di accoppiamento dinamico tra due sistemi passivi in modo flessibile preservando la passività dell'intero sistema accoppiato.Communicating and interacting with a robot are critical tasks in order to make the robot act as desired both in research and industrial scenarios. In this thesis, we developed different methods to interact with robots in many applications. Direct teleoperation allows the user to directly move the robot using some device to impose the motion of the robot. We studied a novel methodology for letting a user teleoperate a robotic system in a natural manner. The proposed approach does not require any specific device but relies on commonly used objects as a smartwatch. Using this approach, it is possible to interact with a mobile robot in an intuitive way by moving the user's forearm. Human-robot collaboration is fundamental when a cooperative tasks has to be done, as in the TIREBOT project. The TIREBOT project consists of the mechanical design and the collaborative control of TIREBOT, a robotic assistant helping tire workshop operators in the wheel replacement process. The operator can interact with the robot using either a gesture based interface or by teleoperation. The robot understands when the user wants to collaborate and when something else happens. In the first scenario, the user is allowed to get close to the robot. In the second case the robot has to move away from the user in order to keep the safety. Industrial applications as agricultural tasks can be labor intensive and can lead to a variety of injuries and illnesses, therefore it can be useful to let the robot do the hard work. In this field, we developed two different robotic systems. The first one is a low-cost autonomous system which can navigate through a vineyard while collecting grape pictures in order to provide a yield estimation. The second system is an apple harvesting robot. The robot can identify the apples in the scene, approach the apple to grasp and detach it from the tree. During the execution of the desired task, the human is not the only agent the robot has to interact with. It has to interact to other robots in order to achieve the desired goal. In multi-robot systems passive interconnections among agents are often exploited to achieve a desired and robustly stable cooperative behavior. We exploit the concept of energy tank for building a novel generalized interconnection that allows to impose any kind of dynamic coupling between two passive systems in a flexible way while preserving the passivity of the overall coupled system
On the Use of Energy Tanks for Multi-Robot Interconnection
No full textIn multi-robot systems passive interconnections among agents are often exploited to achieve a desired and robustly stable cooperative behavior. Nevertheless, the passivity constraint limits the kinds of behaviors that can be achieved. In this paper, we exploit the concept of energy tank for building a novel generalized interconnection that allows to impose any kind of dynamic coupling between two passive systems in a flexible way while preserving the passivity of the overall coupled system. The proposed strategy is validated by simulations and experiments
A Low-Cost Navigation Strategy for Yield Estimation in Vineyards
No full textAccurate yield estimation is very important for improving the vineyard management, the quality of the grapes and the health of the vines. The most common systems use RGB image processing for achieving a good estimation. In order to collect images, robots or farming vehicles can be equipped with a RGB camera. In this paper, we propose a low-cost autonomous system which can navigate through a vineyard while collecting grape pictures in order to provide a yield estimation. Our system uses only a laser scanner to detect the row and follows it until its end, then it navigates towards the next one, exploiting the knowledge of the vineyard. The navigation algorithm was tested both in simulation and in a real environment with good results. Furthermore, a yield estimation of two different grape varieties is presented
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
TIREBOT: A collaborative robot for the tire workshop
No full textCollaborative robots allow to relieve humans from tedious and/or tiring tasks while leaving to the operator high-level activities, where their expertise is needed. In this paper the mechanical design and the collaborative control of TIREBOT, a robotic assistant helping tire workshop operators in the wheel replacement process, is illustrated. The effectiveness of TIREBOT is validated in a real tire-workshop. Furthermore, the possibility of using TIREBOT as an autonomous personal forklift has been validated in an industrial scenario
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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