Orientador: Jacques Wainer / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Computação / Made available in DSpace on 2018-08-24T02:06:24Z (GMT). No. of bitstreams: 1 Pinheiro_PauloGurgel_D.pdf: 41476694 bytes, checksum: f3d5b1e2aa32aa6f00ef7ac689a261e2 (MD5) Previous issue date: 2013 / Resumo: Localização de robôs móveis é uma das áreas mais exploradas da robótica devido a sua importância para a resolução de problemas, como: navegação, mapeamento e SLAM. Muitos trabalhos apresentaram soluções envolvendo cooperação, comunicação e exploração do ambiente, onde em geral a localização é obtida através de ações randômicas ou puramente orientadas pelo estado de crença. Nesta tese, é apresentado um modelo de planejamento para localização utilizando POMDP e Localização de Markov, que indicaria a melhor ação que o robô deve efetuar em cada momento, com o objetivo de diminuir a quantidade de passos. O foco está principalmente em: i) problemas de difícil localização: onde não há landmark ou informação extra no ambiente que auxilie o robô, ii) situações de performance crítica: onde o robô deve evitar passos randômicos e o gasto de energia e, por último, iii) situações com múltiplas missões. Sabendo que um robô é projetado para desempenhar missões, será proposto, neste trabalho, um modelo onde essas missões são consideradas em paralelo com a localização. Planejar para cenários com múltiplos ambientes é um desafio devido a grande quantidade de estados que deve ser tratada. Para esse tipo de problema, será apresentado um modelo de compressão de mapas que utiliza padrões arquiteturais e de design, como: quantidade de portas, paredes ou área total de um ambiente, para condensar informações que possam ser redundantes. O modelo baseia-se na similaridade das características de desing para agrupar ambientes similares e combiná-los, gerando um único mapa representante que possui uma quantidade de estados menor que a soma total de todos os estados dos ambientes do grupo. Planos em POMDP são gerados apenas para os representantes e não para todo o mapa. Finalmente, será apresentado o modelo hierárquico onde a localização é executada em duas camadas. Na camada superior, o robô utiliza os planos POMDP e os mapas compactos para estimar a grossa estimativa de sua localização e, na camada inferior, utiliza POMDP ou Localização de Markov para a obtenção da postura mais precisa. O modelo hierárquico foi demonstrado com experimentos utilizando o simulador V-REP, e o robô Pioneer 3-DX. Resultados comparativos mostraram que o robô utilizando o modelo proposto, foi capaz de realizar o processo de localização em cenários com múltiplos ambientes e cumprir a missão, mantendo a precisão com uma significativa redução na quantidade de passos efetuados / Abstract: Mobile Robot localization is one of the most explored areas in robotics due to its importance for solving problems, such as navigation, mapping and SLAM. In this work, we are interested in solving global localization problems, where the initial pose of the robot is completely unknown. Several works have proposed solutions for localization focusing on robot cooperation, communication or environment exploration, where the robot's pose is often found by a certain amount of random actions or state belief oriented actions. In order to decrease the total steps performed, we will introduce a model of planning for localization using POMDPs and Markov Localization that indicates the optimal action to be taken by the robot for each decision time. Our focus is on i) hard localization problems, where there are no special landmarks or extra features over the environment to help the robot, ii) critical performance situation, where the robot is required to avoid random actions and the waste of energy roaming over the environment, and iii) multiple missions situations. Aware the robot is designed to perform missions, we have proposed a model that runs missions and the localization process, simultaneously. Also, since the robot can have different missions, the model computes the planning for localization as an offline process, but loading the missions at runtime. Planning for multiple environments is a challenge due to the amount of states we must consider. Thus, we also proposed a solution to compress the original map, creating a smaller topological representation that is easier and cheaper to get plans done. The map compression takes advantage of the similarity of rooms found especially in offices and residential environments. Similar rooms have similar architectural design features that can be shared. To deal with the compressed map, we proposed a hierarchical approach that uses light POMDP plans and the compressed map on the higher layer to find the gross pose, and on the lower layer, decomposed maps to find the precise pose. We have demonstrated the hierarchical approach with the map compression using both V-REP Simulator and a Pioneer 3-DX robot. Comparing to other active localization models, the results show that our approach allowed the robot to perform both localization and the mission in a multiple room environment with a significant reduction on the number of steps while keeping the pose accuracy / Doutorado / Ciência da Computação / Doutor em Ciência da Computação

[pt] Neste trabalho é abordado o problema do controle durante o período de transição de contato em manipuladores robóticos. Tipicamente é o controlador de força que deve atuar durante o período transiente, no entanto esse controlador não está preparado para lidar com o fenômeno altamente não-linear que representam os impactos e as perdas de contato. No trabalho, inicialmente é feita uma análise do desempenho e estabilidade dos controladores de força convencionais durante a transição de contato. Essa análise é baseada em modelos simplificados: um de manipulador rígido e outro de flexível. É mostrado que os impactos não originam instabilidade dinâmica mas podem deteriorar severamente o desempenho do sistema. Posteriormente, com a finalidade de obter modelos mais realistas que validassem a efetividade de novos controladores, é desenvolvido um modelo para um manipulador rígido-flexível de dois elos em que se colocam pastilhas piezoelétricas coladas ao longo do braço flexível. Também são estudados modelos de contato. Finalmente, são apresentados três novos controladores que são projetados especificamente para lidar com os impactos e perdas de contato que aparecem na transição de contato. A idéia do primeiro controlador é detectar o primeiro impacto e a partir dele reformular a trajetória que a extremidade do manipulador deverá seguir para atingir a superfície do meio com velocidade mínima, evitando assim outros impactos. O projeto deste controlador é feito usando a teoria de controle ótimo. O segundo controlador baseia-se na linearização do movimento de um manipulador flexível em torno do movimento do manipulador considerado rígido. A equação resultante é usada para projetar um controlador de posição de alta precisão que permite evitar, ou diminuir, a severidade do impacto inicial. A idéia do terceiro controlador é amortecer ativamente a parte flexível do manipulador através das pastilhas piezoelétricas que funcionam como atuadores e sensores colocados de maneira a garantir estabilidade em presença de dinâmica residual. O projeto do controlador é formulado como um problema de otimização que é resolvido através de técnicas de programação não-linear. / [en] In this work it is considered the problem of control during the contact transition period in robotic manipulators. Typically it is the force controller that acts during the transient period, however that controller is not prepared to deal effectively with impacts and losses of contact. In this work, it is initially performed an analysis of the stability and performance of conventional force controllers working during the contact transition. The analysis is based on simplified models for rigid and flexible manipulators. It is proved that the impacts do not cause dynamic instability, but they can severely degrade the system performance. Later, with the purpose of getting more realistic models to validate the effectiveness of new controllers, a model of a two-link rigid-flexible manipulator is developed considering glued piezoelectric sheets along the flexible arm. Contact models are also studied. Finally, three new controllers are presented which are designed to specifically deal with impacts and losses of contact during the contact transition period. The main idea of the first controller is to identify the first and unavoidable impact and then to reformulate the trajectory that the endeffector will follow to approach the collision surface with a minimum velocity, thus preventing new impacts. The controller is designed by using the theory of optimal control. The second controller is based on the equation of the motion of a flexible manipulator linearized around the motion of the manipulator when all the links are considered rigid. The obtained equation is used to design a high precision position controller to prevent or lessen the severity of the initial impact. The idea of the third controller is to actively damp the flexible part of the manipulator through the piezoelectric sheets that act as collocated actuators and sensors, this way the stability in presence of residual dynamics is guaranteed. The controller design is formulated as an optimization problem that is solved through nonlinear programming techniques.

Master of Science / Department of Biological & Agricultural Engineering / Daniel Flippo / Robotic vehicles have the potential to play a key role in the future of agriculture. For this to happen designs that are cost effective, robust, and easy to use will be necessary. Robotic vehicles that can pest scout, monitor crop health, and potentially plant and harvest crops will provide new ways to increase production within agriculture. At this time, the use of robotic vehicles to plant and harvest crops poses many challenges including complexity and power consumption. The incorporation of small robotic vehicles for monitoring and scouting fields has the potential to allow for easier integration of robotic systems into current farming practices as the technology continues to develop. Benefits of using unmanned ground vehicles (UGVs) for crop scouting include higher resolution and real time mapping, measuring, and monitoring of pest location density, crop nutrient levels, and soil moisture levels. The focus of this research is the ability of a UGV to scout pest populations and pest patterns to complement existing scouting technology used on UAVs to capture information about nutrient and water levels. There are many challenges to integrating UGVs in conventionally planted fields of row crops including intra-row and inter-row maneuvering. For intra-row maneuvering; i.e. between two rows of corn, cost effective sensors will be needed to keep the UGV between straight rows, to follow contoured rows, and avoid local objects. Inter-row maneuvering involves navigating from long straight rows to the headlands by moving through the space between two plants in a row. Oftentimes headland rows are perpendicular to the row that the UGV is within and if the crop is corn, the spacing between plants can be as narrow as 5”. A vehicle design that minimizes or eliminates crop damage when inter-row maneuvering occurs will be very beneficial and allow for earlier integration of robotic crop scouting into conventional farming practices. Using three fixed HC-SR04 ultrasonic sensors with LabVIEW programming proved to be a cost effective, simple, solution for intra-row maneuvering of an unmanned ground vehicle through a simulated corn row. Inter-row maneuvering was accomplished by designing a transformable tracked vehicle with the two configurations of the tracks being parallel and linear. The robotic vehicle operates with tracks parallel to each other and skid steering being the method of control for traveling between rows of corn. When the robotic vehicle needs to move through narrow spaces or from one row to the next, two motors rotate the frame of the tracks to a linear configuration where one track follows the other track. In the linear configuration the vehicle has a width of 5 inches which allows it to move between corn plants in high population fields for minimally invasive maneuvers. Fleets of robotic vehicles will be required to perform scouting operations on large fields. Some robotic vehicle operations will require coordination between machines to complete the tasks assigned. Simulation of the path planning for coordination of multiple machines was studied within the context of a non-stationary traveling salesman problem to determine optimal path plans.

Durante o processo de desenvolvimento de software a atividade de teste pode contribuir com a melhoria de qualidade, produtividade e redução de custos, por meio da aplicação de técnicas e critérios de teste. Esses instrumentos viabilizam a detecção de defeitos, minimizando a quantidade de falhas no produto final. Durante o desenvolvimento de sistemas robóticos móveis, técnicas VST (Virtual Simulation Tools/Technology) são enormemente utilizadas. Apesar dos testes usando simulação serem eficientes em alguns casos, eles não permitem uma sistematização da atividade de teste com relação à cobertura de código. Este projeto de doutorado contribui nessa direção, explorando essa lacuna e propondo uma abordagem de teste de integração híbrida, composta por teste funcional e estrutural, a qual explora defeitos relacionados à comunicação entre os processos do sistema robótico. Este estudo foi conduzido com base em conceitos explorados no teste de programas concorrentes, dado que os sistemas robóticos podem apresentar problemas similares aos encontrados nos programas concorrentes, como não determinismo, diferentes possibilidades de comunicação, entre outros. Durante o trabalho foi definida uma abordagem de teste de integração e critérios de cobertura aplicados a sistemas robóticos. Os estudos exploratórios conduzidos indicaram que a abordagem proposta é aplicável e pode contribuir para revelar defeitos não explorados pela simulação e técnicas de teste utilizadas anteriormente. / During the software development process the test activity contributes in terms of increased software quality, team productivity and cost reduction by application of techniques and test criteria. These mechanisms allow the defects detection, reducing the failures in the final product. In a robotic systems development context, VST techniques (Virtual Simulation Tools/Technology) are widely used. Although these approaches be efficient, in some cases they not allow great systematization of the test activity including code coverage analysis. This project explores this gap and proposes an approach for integration testing applied to robotic embedded systems, composed of functional and structural testing, looking for defects mainly related to the communication among processes of these systems. This study was initially conducted by mapping coverage criteria, defined for concurrent programs testing and exploring problems related to non-determinism, communication, and other undesired situations. During the project we defined an approach of integration testing and coverage criteria for mobile robotic systems. The exploratory case studies indicate that the proposed approach is applicable and can contributes to reveal defects not found using simulations or traditional testing of mobile robotic systems.

A robótica tem passado por uma notável evolução ao longo dos últimos anos, juntamente com um crescente interesse por parte da sociedade. Robôs não são mais exclusivamente produzidos para realizar atividades repetitivas em fábricas, eles têm sido projetados para apoiar humanos em diversos e importantes domínios de aplicação. Os sistemas robóticos utilizados para controlar tais robôs têm, portanto, se tornado maiores, mais complexos e difíceis de desenvolver. Nesse cenário, a Arquitetura Orientada a Serviços (do inglês, Service-Oriented Architecture - SOA) tem sido investigada como um promissor estilo arquitetural para o desenvolvimento de sistemas robóticos de forma mais flexível, reusável e produtiva. Embora um número considerável de Sistemas Robóticos Orientados a Serviços (do inglês, Service-Oriented Robotic Systems - SORS) já exista, grande parte deles têm sido desenvolvida de maneira ad hoc. A pouca atenção e o suporte limitado ao projeto das arquiteturas de software de SORS pode não só impedir a obtenção dos benefícios associados à adoção da SOA, mas também reduzir a qualidade dos sistemas robóticos que, frequentemente, são utilizados em contextos de segurança crítica. Essa tese tem por objetivo aprimorar o entendimento e a sistematização do projeto arquitetural de SORS. Para isso, é proposta uma taxonomia de serviços para o domínio de robótica, bem como um processo e uma arquitetura de referência para sistematizar o projeto das arquiteturas de software de SORS. Os resultados obtidos evidenciam que tanto o processo quanto a arquitetura de referência podem impactar positivamente na qualidade das arquiteturas de software de SORS e, consequentemente, contribuir para o desenvolvimento de sistemas robóticos. / Robotics has experienced an increasing evolution and interest from the society in recent years. Robots are no longer produced exclusively to perform repetitive tasks in factories, they have been designed to collaborate with humans in several important application domains. Robotic systems that control these robots are therefore becoming larger, more complex, and difficult to develop. In this scenario, Service-Oriented Architecture (SOA) has been investigated as a promising architectural style for the design of robotic systems in a exible, reusable, and productive manner. Despite the existence of a considerable amount of Service-Oriented Robotic Systems (SORS), most of them have been developed in an ad hoc manner. The little attention and limited support devoted to the design of SORS software architectures may not only hamper the benefits of SOA adoption, but also reduce the overall quality of robotic systems, which are often used in safety-critical contexts. This thesis aims at improving the understanding and systematization of SORS architectural design. It describes a taxonomy of services for the robotics domain, as well as proposes a process and a reference architecture that systematize the design of SORS software architectures. Results achieved in the evaluation studies evidence that both process and reference architecture can positively impact on the quality of SORS software architectures and, as a consequence, contribute to the development of robotic systems.

abstract: Robotic lower limb prostheses provide new opportunities to help transfemoral amputees regain mobility. However, their application is impeded by that the impedance control parameters need to be tuned and optimized manually by prosthetists for each individual user in different task environments. Reinforcement learning (RL) is capable of automatically learning from interacting with the environment. It becomes a natural candidate to replace human prosthetists to customize the control parameters. However, neither traditional RL approaches nor the popular deep RL approaches are readily suitable for learning with limited number of samples and samples with large variations. This dissertation aims to explore new RL based adaptive solutions that are data-efficient for controlling robotic prostheses. This dissertation begins by proposing a new flexible policy iteration (FPI) framework. To improve sample efficiency, FPI can utilize either on-policy or off-policy learning strategy, can learn from either online or offline data, and can even adopt exiting knowledge of an external critic. Approximate convergence to Bellman optimal solutions are guaranteed under mild conditions. Simulation studies validated that FPI was data efficient compared to several established RL methods. Furthermore, a simplified version of FPI was implemented to learn from offline data, and then the learned policy was successfully tested for tuning the control parameters online on a human subject. Next, the dissertation discusses RL control with information transfer (RL-IT), or knowledge-guided RL (KG-RL), which is motivated to benefit from transferring knowledge acquired from one subject to another. To explore its feasibility, knowledge was extracted from data measurements of able-bodied (AB) subjects, and transferred to guide Q-learning control for an amputee in OpenSim simulations. This result again demonstrated that data and time efficiency were improved using previous knowledge. While the present study is new and promising, there are still many open questions to be addressed in future research. To account for human adaption, the learning control objective function may be designed to incorporate human-prosthesis performance feedback such as symmetry, user comfort level and satisfaction, and user energy consumption. To make the RL based control parameter tuning practical in real life, it should be further developed and tested in different use environments, such as from level ground walking to stair ascending or descending, and from walking to running. / Dissertation/Thesis / Doctoral Dissertation Electrical Engineering 2020

De la mondialisation à la globalisation, de la modernité à la postmodernité, de l"humain au transhumain : - la révolution numérique et technologique fait émerger des enjeux qui imprègnent notre quotidien au-delà même de ce que le sens commun peut imaginer. La massification des données, analysée comme la résultante d'une hyper-connectivité, liée à une convergence « big data-intelligence artificielle » pose la question de sa juste utilisation et répartition entre des acteurs privés très volontaristes (GAFA) et des institutions publics pour le moins dépassées, quant aux principes d'efficacité rationnelle représentant l'une des caractéristiques des datas. Une caractéristique prédictive qui correspond donc à un besoin vital des états. Une société humaine qui disposerait des connaissances précises de sa situation, pourrait faire des choix rationnels en fonction de scénarios prédictifs et n'agirait plus de la même façon et ne se normaliserait plus de la même façon. Si nous rejetons le transhumanisme dans sa dimension idéologique, nous prenons pour acquises les dimensions conceptuelles de la théorie dite de la singularité que nous problématisons dans ce travail par une analyse de l'information propre à une démarche d'intelligence économique, au-delà même de la pensée commune et d'un consensus hérité d'une école de pensée déductive qui s'est affirmée par la démonstration et imposée par une forme d'idéologie qui existe partout, si ce n'est dans les sciences sociales. La pensée inductive, dont la caractéristique première est la corrélation à vocation prédictive, verrait l'élaboration de scénarios probabilistes multidisciplinaires, audacieux et propres à la science politique, dont l'idée principale serait de détecter et d'anticiper, à l'instar de la médecine prédictive (c'est ce que nous dit la singularité), les grandes tendances sociétales et politiques futures. Cependant, la nature de ces travaux devra faire l'objet d'une indépendance totale. Le processus d'exploitation du big data par le biais d'algorithmes, hors processus traditionnels de validation scientifique, prendra appui sur un modèle nouveau, dans lequel la démonstration de la cause prendra sans doute une dimension quantique ou synaptique dans un futur proche, analysé ainsi, comme singulier. / From past world to globalization, from modernity to postmodernity, from the human to the transhuman: - the digital and technological revolution brings out issues that permeate our daily lives beyond even what common sense can imagine. The massification of data, analyzed as the result of a hyper-connectivity, linked to a convergence "big data-artificial intelligence" raises the question of its fair use and distribution between highly voluntary private actors (GAFA) and public institutions for the least outdated, as to the principles of rational efficiency representing one of the characteristics of datas. A predictive characteristic that corresponds to a vital need of states. A human society with specific knowledge of its situation could make rational choices based on predictive scenarios and would no longer behave in the same way and no longer normalize in the same way. If we reject transhumanism in its ideological dimension, we take for granted the conceptual dimensions of the theory of singularity that we problematize in this work by an analysis of information specific to an approach of economic intelligence, even beyond of common thought and consensus inherited from a deductive school of thought that has been affirmed by demonstration and imposed by a form of ideology that exists everywhere, if not in social sciences. Inductive thinking, whose primary characteristic is predictive correlation, would see the development of probabilistic, multidisciplinary, bold and peculiar political science scenarios, the main idea of which would be to detect and anticipate, as predictive medicine (this is what singularity tells us), major societal and political future trends. However, the nature of this work will have to be fully independent. The process of exploiting big data by means of algorithms, outside traditional processes of scientific validation, will be based on a new model, in which the proof of the cause will undoubtedly take on a quantum or synaptic dimension in a near future, analyzed thus, as singular.

Organisations in the public sector are facing tough challenges and need to review alternative ways of working. Robotic process automation (RPA) is a technology that is becoming a more common way to automate processes in order to become more efficient as an organization. However, the majority of studies on RPA are focused on companies in the private sector. Through a qualitative case study, we investigate the effects that RPA has on a organisation in the public sector. This study finds effects such as time savings, liberation from tedious tasks, reduced number of employees and increased productivity. Preparation before the implementation of RPA, in particular process mapping, has proven to be a factor that has a significant impact on the outcomes. In general, RPA is perceived as something positive within the studied case. The study shows that there is potential in automating public sector processes with RPA, however there seems to be some challenges with RPA as well, such as the loss of human social interpretation when a human is replaced by a robot.

The current issue of Visceral Medicine focuses on colorectal cancer. Despite intense screening efforts, colorectal cancer still belongs to the most frequent cancers in both males and females in the EU. Particularly in rectal cancer there have been major developments in the surgical techniques over the last years that have led to a substantial reduction in local disease recurrence.

<div>This dissertation broadly focuses on autonomous condition assessment of civil infrastructures using vision-based methods, which present a plausible alternative to existing manual techniques. A region-based convolutional neural network (Faster R-CNN) is exploited for the detection of various earthquake-induced damages in reinforced concrete buildings. Four different damage categories are considered such as surface crack, spalling, spalling with exposed rebars, and severely buckled rebars. The performance of the model is evaluated on image data collected from buildings damaged under several past earthquakes taking place in different parts of the world. The proposed algorithm can be integrated with inspection drones or mobile robotic platforms for quick assessment of damaged buildings leading to expeditious planning of retrofit operations, minimization of damage cost, and timely restoration of essential services. </div><div><br></div><div> </div><div> Besides, a computer vision-based approach is presented to track the evolution of a damage over time by analysing historical visual inspection data. Once a defect is detected in a recent inspection data set, its spatial correspondences in the data collected during previous rounds of inspection are identified leveraging popular computer vision-based techniques. A single reconstructed view is then generated for each inspection round by synthesizing the candidate corresponding images. The chronology of damage thus established facilitates time-based quantification and lucid visual interpretation. This study is likely to enhance the efficiency structural inspection by introducing the time dimension into the autonomous condition assessment pipeline.</div><div><br></div><div> </div><div> Additionally, this dissertation incorporates depth fusion into a CNN-based semantic segmentation model. A 3D animation and visual effect software is exploited to generate a synthetic database of spatially aligned RGB and depth image pairs representing various damage categories which are commonly observed in reinforced concrete buildings. A number of encoding techniques are explored for representing the depth data. Besides, various schemes for fusion of RGB and depth data are investigated to identify the best fusion strategy. It was observed that depth fusion enhances the performance of deep learning-based damage segmentation algorithms significantly. Furthermore, strategies are proposed to manufacture depth information from corresponding RGB frame, which eliminates the need of depth sensing at the time of deployment without compromising on segmentation performance. Overall, the scientific research presented in this dissertation will be a stepping stone towards realizing a fully autonomous structural condition assessment pipeline.</div>