A flexible navigation system for autonomous robots operating in heterogeneous environments

Dissertação para obtenção do Grau de Mestre em Engenharia Electrotécnica e de Computadores

Robots and humans as co-workers? The human-centred perspective of work with autonomous systems

The design of work organisation systems with automated equipment is facing new challenges and the emergence of new concepts. The social aspects that are related with new concepts on the complex work environments (CWE) are becoming more relevant for that design. The work with autonomous systems implies options in the design of workplaces. Especially that happens in such complex environments. The concepts of “agents”, “co-working” or “human-centred technical systems” reveal new dimensions related to human-computer interaction (HCI). With an increase in the number and complexity of those human-technology interfaces, the capacities of human intervention can become limited, originating further problems. The case of robotics is used to exemplify the issues related with automation in working environments and the emergence of new HCI approaches that would include social implications. We conclude that studies on technology assessment of industrial robotics and autonomous agents on manufacturing environment should also focus on the human involvement strategies in organisations. A needed participatory strategy implies a new approach to workplaces design. This means that the research focus must be on the relation between technology and social dimensions not as separate entities, but integrated in the design of an interaction system.

Child programming: an adequate domain specific language for programming specific robots

Dissertação para obtenção do Grau de Mestre em Engenharia Informática

A volumetric hybrid representation for obstacle detection in all-terrain robots

This dissertation presents an approach aimed at three-dimensional perception’s obstacle detection on all-terrain robots. Given the huge amount of acquired information, the adversities such environments present to an autonomous system and the swiftness, thus required, from each of its navigation decisions, it becomes imperative that the 3-D perceptional system to be able to map obstacles and passageways in the most swift and detailed manner. In this document, a hybrid approach is presented bringing the best of several methods together, combining the lightness of lesser meticulous analyses with the detail brought by more thorough ones. Realizing the former, a terrain’s slope mapping system upon a low resolute volumetric representation of the surrounding occupancy. For the latter’s detailed evaluation, two novel metrics were conceived to discriminate the little depth discrepancies found in between range scanner’s beam distance measurements. The hybrid solution resulting from the conjunction of these two representations provides a reliable answer to traversability mapping and a robust discrimination of penetrable vegetation from that constituting real obstructions. Two distinct robotic platforms offered the possibility to test the hybrid approach on very different applications: a boat, under an European project, the ECHORD Riverwatch, and a terrestrial four-wheeled robot for a national project, the Introsys Robot.

AGNI: an API for the control of automomous service robots

With the continuum growth of Internet connected devices, the scalability of the protocols used for communication between them is facing a new set of challenges. In robotics these communications protocols are an essential element, and must be able to accomplish with the desired communication. In a context of a multi-­‐‑agent platform, the main types of Internet communication protocols used in robotics, mission planning and task allocation problems will be revised. It will be defined how to represent a message and how to cope with their transport between devices in a distributed environment, reviewing all the layers of the messaging process. A review of the ROS platform is also presented with the intent of integrating the already existing communication protocols with the ServRobot, a mobile autonomous robot, and the DVA, a distributed autonomous surveillance system. This is done with the objective of assigning missions to ServRobot in a security context.

Context classification for service robots

This dissertation presents a solution for environment sensing using sensor fusion techniques and a context/environment classification of the surroundings in a service robot, so it could change his behavior according to the different rea-soning outputs. As an example, if a robot knows he is outdoors, in a field environment, there can be a sandy ground, in which it should slow down. Contrariwise in indoor environments, that situation is statistically unlikely to happen (sandy ground). This simple assumption denotes the importance of context-aware in automated guided vehicles.

Towards human-like bimanual movements in anthropomorphic robots: a nonlinear optimization approach

Previously we have presented a model for generating human-like arm and hand movements on an unimanual anthropomorphic robot involved in human-robot collaboration tasks. The present paper aims to extend our model in order to address the generation of human-like bimanual movement sequences which are challenged by scenarios cluttered with obstacles. Movement planning involves large scale nonlinear constrained optimization problems which are solved using the IPOPT solver. Simulation studies show that the model generates feasible and realistic hand trajectories for action sequences involving the two hands. The computational costs involved in the planning allow for real-time human robot-interaction. A qualitative analysis reveals that the movements of the robot exhibit basic characteristics of human movements.

Contact processing within walking robots' design

Magdeburg, Univ., Fak. für Elektrotechnik und Informationstechnik, Diss., 2011

L' Ensenyament per tasques: programació d'una assignatura de traducció de l'alemany a l'espanyol

In this work we present a proposal for a course in translation from German into Spanish following the task based approach as known in second language acquisition. The aim is to improve the translation competence of translation students. We depart from the hypothesis that some students select inapropiate translation strategies when faced with certain translation problems leading them to translation errors. In order to avoid these translation errors originated by wrong application of such strategies we propose a didactic method which helps to prevent them by a) raising awareness of the different subcompetences required while translating, b) improving the ability to identify translation problems and relate them to the different subcompetences and c) enhancing the use of the most adequate strategy according to the characteristics of each problem. With regard to translation and how translation competence is acquired our work follows the communicative approach to translation theory as defended among others by Hatim & Mason (1990), Lörscher (1992) and Kiraly (1995), where translation is seen as a communicative activity which can be analized from a psycholinguistic perspective. In this sense we give operative definitions for what we understand by “translation problem”, “translation strategy”, “translation error”, “translation competence” and “translation”. Our approach to didactics adapts recent developments in Second Language Teaching within the communicative paradigm as is the task based approach by Nunan (1989) acquisition to translation. Fitting the recquirements of this pedagogic approach we present a planning for a translation course which is compatible with present translation studies.

Estudiant suite: la programació client-servidor

Treball de recerca realitzat per un alumne d’ensenyament secundari i guardonat amb un Premi CIRIT per fomentar l'esperit científic del Jovent l’any 2006. Mitjançant un programa informàtic, creat per un estudiant de batxillerat, els alumnes compartiran, a través d’internet,resums o fitxers amb informació rellevant sobre les matèries que estan estudiant sense la necessitat de coincidir en línia. El programa servidor permet donar d'alta i de baixa usuaris, control e les connexions i dels fitxers. A més a més s'encarrega d'emmagatzemar i codificar la informació (fitxers) que aporten els usuaris. El client permet l'identificació mitjançant un nom d'usuari i una contrasenya i la visualització de la informació que conté el servidor, com també permet l'aportació i modificació d'aquesta.

Extracció de tasques locals d'un itinerari protegit per arquitectures criptogràfiques

En aquest projecte s'ha realitzat una ampliació del llenguatge de protecció d'itineraris d'agents mòbils i la seva implementació per tal d'extreure'n les tasques locals. Aquestes tasques es troben encriptades dintre de l'itinerari de l'agent i descriuen el comportament que tindrà, així que és necessària una classe que les sàpiga extreure. El nostre compilador crea aquesta classe a partir de l'arquitectura d'extracció. L'hem provat amb les arquitectures simple i nested i els resultats amb itineraris reals han estat els esperats. A la pràctica, aquest projecte completa una mica més l'entorn de desenvolupament integrat d'agents mòbils MARISM-A.

Generic object classification for autonomous robots

Un dels principals problemes de la interacció dels robots autònoms és el coneixement de l'escena. El reconeixement és fonamental per a solucionar aquest problema i permetre als robots interactuar en un escenari no controlat. En aquest document presentem una aplicació pràctica de la captura d'objectes, de la normalització i de la classificació de senyals triangulars i circulars. El sistema s'introdueix en el robot Aibo de Sony per a millorar-ne la interacció. La metodologia presentada s'ha comprobat en simulacions i problemes de categorització reals, com ara la classificació de senyals de trànsit, amb resultats molt prometedors.

Modelo de un grupo de robots colaboradores cazadores

El nombre d'aplicacions dels microrobots en biomedicina creix a mesura que el seu desenvolupament avança. Entre elles hi ha les consistents a examinar cèl·lules amb microrobots cooperants. En aquest treball es presenta un prototip a escala d'aquest problema, convenientment simplificat: dos robots tracten d'agafar una pilota que representa la cèl·lula que s'examina. Com a resultat, s'ha obtingut un algorisme deliberatiu per a la resolució d'aquest problema amb robots homogenis.

Simulació d'un sistema OFDM per a canals mòbils selectius en freqüència

La següent memòria pretén recollir com simular un sistema amb modulació multiportadora; en concret OFDM, per a canals mòbils. L’estudi contempla la capa física del sistema, que s’encarrega de transmetre les cadenes de bits d’informació entre els transmissor i el receptor. L’objectiu és simular el sistema OFDM per a canals mòbils, veure com es comporta i discutir els diferents factors que influeixen en la qualitat de l’enllaç.

Sistema de missatgeria per a mòbils basat en xarxes Wi-Fi

El projecte sobre el que versa la present memòria pretén dur a terme l’anàlisi, disseny i implementació d’un sistema de missatgeria per a mòbils basat en xarxes Wi-Fi. Amb aquest propòsit, i amb posterioritat a la valoració de totes les alternatives i eines disponibles, s’ha desenvolupat una aplicació en llenguatge J2ME amb configuració CLDC 1.1 i perfil MIDP 2.0.