Localization of a mobile robot based on odometry and natural landmarks using extended kalman filter

SANTANA, André M.; SOUZA, Anderson A. S.; BRITTO, Ricardo S.; ALSINA, Pablo J.; MEDEIROS, Adelardo A. D. Localization of a mobile robot based on odometry and natural landmarks using extended Kalman Filter. In: INTERNATIONAL CONFERENCE ON INFORMATICS IN CONTROL, AUTOMATION AND ROBOTICS, 5., 2008, Funchal, Portugal. Proceedings... Funchal, Portugal: ICINCO, 2008.

Controle vetorial para velocidade de um motor de indução trifásico utilizando estimador filtro de Kalman

This paper describes the study, computer simulation and feasibility of implementation of vector control speed of an induction motor using for this purpose the Extended Kalman Filter as an estimator of rotor flux. The motivation for such work is the use of a control system that requires no sensors on the machine shaft, thus providing a considerable cost reduction of drives and their maintenance, increased reliability, robustness and noise immunity as compared to control systems with conventional sensors

Localization of a mobile robot based on odometry and natural landmarks using extended kalman filter

SANTANA, André M.; SOUZA, Anderson A. S.; BRITTO, Ricardo S.; ALSINA, Pablo J.; MEDEIROS, Adelardo A. D. Localization of a mobile robot based on odometry and natural landmarks using extended Kalman Filter. In: INTERNATIONAL CONFERENCE ON INFORMATICS IN CONTROL, AUTOMATION AND ROBOTICS, 5., 2008, Funchal, Portugal. Proceedings... Funchal, Portugal: ICINCO, 2008.

Real-Time Visual SLAM Using Pre - Existing Floor Lines as Landmarks and a Single Camera

SANTANA, André M.; SANTIAGO, Gutemberg S.; MEDEIROS, Adelardo A. D. Real-Time Visual SLAM Using Pre-Existing Floor Lines as Landmarks and a Single Camera. In: CONGRESSO BRASILEIRO DE AUTOMÁTICA, 2008, Juiz de Fora, MG. Anais... Juiz de Fora: CBA, 2008.

Avaliação de heterociclo do tipo mesoiônico solubilizado em sistema microemulsionado para aplicação em dutos

The efficiency of inhibition to corrosion of steel AISI 1018 of surfactant coconut oil saponified (SCO) and heterocyclic type mesoionics (1,3,4-triazólio-2-tiolato) in systems microemulsionados (SCO-ME and SCO-ME-MI) Of type O/A (rich in water emulsion) region with the work of Winsor IV. The systems microemulsionados (SCO-ME and SCO-ME-MI) were evaluated with a corrosion inhibitor for use in saline 10,000 ppm of chloride enriched with carbon dioxide (CO2). The assessment of corrosion inhibitors were evaluated by the techniques of linear polarization resistance (LPR) and loss of weight (MW) in a cell instrumented given the gravity and electrochemical devices. The systems were shooting speed of less than 60 minutes and efficiency of inhibition [SCO-ME (91.25%) and SCO-ME-MI (98.54%)]

A aplicação dos temas transversais nas aulas de educação física - ensino médio integrado

A escola tem se guiado por ações pedagógicas do professor consideravelmente limitadas, as quais têm dificultado configurar com nitidez intenções educativas que contemplam a sua organização curricular. Nesse sentido, esta dissertação tem por objetivo apresentar uma experiência pedagógica da educação física a partir da operacionalização de temas transversais com os conteúdos curriculares no ensino médio integrado no IFRN, campus SGA. Os fundamentos teórico-metodológicos seguiram a linha qualitativa da pesquisa-ação. Participaram desta pesquisa estudantes dos cursos de Edificações e Informática do 1º ano do ensino médio integrado e a professora-pesquisadora, que é servidora efetiva do instituto. Optando pela pesquisa-ação, estruturamos uma intervenção pedagógica com intenção de promover a construção de conhecimento dos conteúdos da educação física com os temas transversais, tanto em amplitude como em profundidade, alicerçada no aporte teórico da teoria da ação dialógica (FREIRE, 2011) e da concepção aberta no ensino da educação física (HILDEBRANDT, 1986). A pesquisa teve como procedimentos a observação participante e a filmagem das aulas de educação física. As observações e os discursos dos estudantes foram organizados em categorias de questões, a saber: 1. Percepção dos estudantes sobre a educação física; 2. Sentidos e significados dos conteúdos da educação física na interfase com os temas transversais nas aulas; 3. Diálogos sobre a interação do conhecimento na relação professor-estudante. As observações e a análise dos depoimentos dos estudantes apontaram, em alguns momentos, que as aulas de educação física ainda são estruturadas no modelo rola bola , sem planejamento, configurando-se mera atividade, e não como prática pedagógica que trata dos saberes do campo da cultura de movimento. Por não constituir-se prática pedagógica que aborda os conteúdos de forma sistematizada, não se tem de forma precisa a ordenação e sequenciação dos aprendizados de práticas corporais, tampouco a introdução de temas transversais, os quais não poderiam ser aprendidos sem uma ação pedagógica concreta do professor. A interação professor-estudante afetiva e dialógica favoreceu que os estudantes se permitissem participar das experiências corporais de um jeito diferente, aceitando aprender os conteúdos curriculares em conjunto com os temas transversais, passando a perceber as aulas de educação física como espaços de experiências de movimento que lhes permitiram atribuir sentido/significado, além do conhecimento sobre o universo da cultura de movimento. A nosso ver, acrescentamos também que a escola não valorizou o trabalho com os temas transversais, pois a recente discussão sobre a inserção desses temas como temáticas relevantes, que devem ser tratadas pedagogicamente em conjunto nos componentes curriculares, ainda não é contemplada expressivamente no projeto curricular da escola

Conhecimentos sobre o corpo: uma possibilidade de intervenção pedagógica nas aulas de educação física no ensino médio

The following study aims at the main conceptions around the body and the learning through physical education classes at school. Therefore, this research mainly presents a proposal of pedagogical intervention on physical education for Ensino Médio, centered on the knowledge about the body as well as how to evaluate the impacts of such interventions on the students‟ learning process. In order to surround our field of investigation, this work elaborates the following study questions: a) What have students learned about the body in physical education classes in Ensino Médio at IFRN? b) What methodological possibilities can contribute on the experience of meaningful learning processes in physical education in Ensino Médio related to the knowledge of body aspects? Regarding to the methodology used, this ethnographic research used several instruments for data collecting like dairies, diagnostic activities, self-assessment evaluations, portfolio, filming, photographs and posts on the social network facebook. The materialization of the pedagogical intervention and all of its implications allow us to consider that the physical education classes in Ensino Médio at IFRN, campus Parnamirim have supported meaningful experiences of learning. Also they motivate relevant discussions applicable to the students‟ everyday lives once they are supported by discussions related to the influence of media about the body of teenagers, the irregular use of steroids, massaging as a possibility of body relaxation. Also, we point out that the students had the chance to experience body activities which crossed the limits of physical education classes‟ hegemony at school, such as indoor soccer, dodgeball, volleyball, basketball and handball. Thus, the students could experience body activities beyond the limits of most common sports, which started several discussions about the juvenile universe and culture. Beside the professional and personal importance of this work, we list the scientific relevance for the production of knowledge on the educational field once the number of Works about the knowledge of the body are still only a few. This study is mainly about alternative body practices. Therefore, we consider that the knowledge about the body can and must be studied not only through alternative practices, but also in different approaches which can be attributed to body running phenomenon. Finally, we believe that the discussions hereby motivated about the matter are far from being enough, so we deliver our intention in deepening this study on forthcoming researches about the knowledge of the body in the field of physical education in Ensino Médio

A sistematização do conteúdo jogo nas aulas de educação física do ensino fundamental e médio

Since the enactment of LDBEN 9.9394/96, Physical Education began to be understood as a curricular component in school. Thus, we see the need for systematization of content. We observed that the physical education classes at the public schools in Natal/RN from the game content, teachers did not use the existing proposals for systematization. And it was on this reality that the study occurred, aiming to present and discuss a proposal to systematization the game content in physical education classes in elementary and secondary education. Accordingly, we departed of following question: What possibilities of systematization of the game content in school physical education classes?. The methodology used was the action research, which allowed us to structure the intervention plan for the game content, directed to a reflective didactic process. The dialogue with action research provided an opportunity to understand of the proposal of systematization, the knowledge of game content, the planning and process of teaching and learning in physical education lessons developed. We use the proposed systematization the book Educação Física Escolar e Organização Curricular , to direct and organize the lesson plans. As research technique, we use the participant observation, filming, photographic records and field diary, guiding us in the debates and discussions about the field of research. The applications of the lesson plans were carried out in three schools, all located in Natal / RN: Escola Municipal Professora Ivonete Maciel, Escola Municipal Professor Ulisses de Góis e Professor Escola Estadual Josino Macedo. The members of this study were students PIBID-EF-UFRN, teachers, supervisors and school. They made the bridge between research and action, theoretical foundation and pedagogical practice, university and school. The results were advanced for beyond the propositions submitted by the above-mentioned book. For the Elementary School 1, the proposed systematization broadened experiences and learning of knowledge of the game and of playful and body manifestations. Provided an opportunity to know and learn about game of make account, rules, popular games, cooperative games, among others. For Elementary Schools 2 and Middle education, systematized lessons allowed the practical, the incorporation of knowledge of the game and its features: such as rules, origin, meaning of the name, different denominations, among others. The students experienced and learned, popular games, pre-sport games, cooperative games, with recycled material, among others. The treatment from three dimensions of contents: procedural, conceptual and attitudinal, occurred parallel to approach the game content, and in conjunction with our interventions, not being done separately during practice, but an ongoing process during class. This new perspective of work the game, in a systematized way, with applying, description and discussion the activities, allowed elaborate a summary framework of thematizations for game content, by year of teaching

Sistema de detecção e isolamento de falhas em sistemas dinâmicos baseado em identificação paramétrica

The present research aims at contributing to the area of detection and diagnosis of failure through the proposal of a new system architecture of detection and isolation of failures (FDI, Fault Detection and Isolation). The proposed architecture presents innovations related to the way the physical values monitored are linked to the FDI system and, as a consequence, the way the failures are detected, isolated and classified. A search for mathematical tools able to satisfy the objectives of the proposed architecture has pointed at the use of the Kalman Filter and its derivatives EKF (Extended Kalman Filter) and UKF (Unscented Kalman Filter). The use of the first one is efficient when the monitored process presents a linear relation among its physical values to be monitored and its out-put. The other two are proficient in case this dynamics is no-linear. After that, a short comparative of features and abilities in the context of failure detection concludes that the UFK system is a better alternative than the EKF one to compose the architecture of the FDI system proposed in case of processes of no-linear dynamics. The results shown in the end of the research refer to the linear and no-linear industrial processes. The efficiency of the proposed architecture may be observed since it has been applied to simulated and real processes. To conclude, the contributions of this thesis are found in the end of the text

Localização e mapeamento simultâneos de ambientes planos usando visão monocular e representação híbrida do ambiente

The goal of this work is to propose a SLAM (Simultaneous Localization and Mapping) solution based on Extended Kalman Filter (EKF) in order to make possible a robot navigates along the environment using information from odometry and pre-existing lines on the floor. Initially, a segmentation step is necessary to classify parts of the image in floor or non floor . Then the image processing identifies floor lines and the parameters of these lines are mapped to world using a homography matrix. Finally, the identified lines are used in SLAM as landmarks in order to build a feature map. In parallel, using the corrected robot pose, the uncertainty about the pose and also the part non floor of the image, it is possible to build an occupancy grid map and generate a metric map with the obstacle s description. A greater autonomy for the robot is attained by using the two types of obtained map (the metric map and the features map). Thus, it is possible to run path planning tasks in parallel with localization and mapping. Practical results are presented to validate the proposal

Localização e planejamento de caminhos para um robô humanóide e um robô escravo com rodas

This work presents the localization and path planning systems for two robots: a non-instrumented humanoid and a slave wheeled robot. The localization of wheeled robot is made using odometry information and landmark detection. These informations are fused using a Extended Kalman Filter. The relative position of humanoid is acquired fusing (using another Kalman Filter) the wheeled robot pose with the characteristics of the landmark on the back of humanoid. Knowing the wheeled robot position and the humanoid relative position in relation to it, we acquired the absolute position of humanoid. The path planning system was developed to provide the cooperative movement of the two robots,incorporating the visibility restrictions of the robotic system

Navegação cooperativa de um robô humanóide e um robô com rodas usando informação visual

This work presents a cooperative navigation systemof a humanoid robot and a wheeled robot using visual information, aiming to navigate the non-instrumented humanoid robot using information obtained from the instrumented wheeled robot. Despite the humanoid not having sensors to its navigation, it can be remotely controlled by infra-red signals. Thus, the wheeled robot can control the humanoid positioning itself behind him and, through visual information, find it and navigate it. The location of the wheeled robot is obtained merging information from odometers and from landmarks detection, using the Extended Kalman Filter. The marks are visually detected, and their features are extracted by image processing. Parameters obtained by image processing are directly used in the Extended Kalman Filter. Thus, while the wheeled robot locates and navigates the humanoid, it also simultaneously calculates its own location and maps the environment (SLAM). The navigation is done through heuristic algorithms based on errors between the actual and desired pose for each robot. The main contribution of this work was the implementation of a cooperative navigation system for two robots based on visual information, which can be extended to other robotic applications, as the ability to control robots without interfering on its hardware, or attaching communication devices

Modelagem e controle de um microveículo aéreo: uma aplicação de estabilidade robusta com a técnica backstepping em uma estrutura hexarrotor

In this Thesis, the development of the dynamic model of multirotor unmanned aerial vehicle with vertical takeoff and landing characteristics, considering input nonlinearities and a full state robust backstepping controller are presented. The dynamic model is expressed using the Newton-Euler laws, aiming to obtain a better mathematical representation of the mechanical system for system analysis and control design, not only when it is hovering, but also when it is taking-off, or landing, or flying to perform a task. The input nonlinearities are the deadzone and saturation, where the gravitational effect and the inherent physical constrains of the rotors are related and addressed. The experimental multirotor aerial vehicle is equipped with an inertial measurement unit and a sonar sensor, which appropriately provides measurements of attitude and altitude. A real-time attitude estimation scheme based on the extended Kalman filter using quaternions was developed. Then, for robustness analysis, sensors were modeled as the ideal value with addition of an unknown bias and unknown white noise. The bounded robust attitude/altitude controller were derived based on globally uniformly practically asymptotically stable for real systems, that remains globally uniformly asymptotically stable if and only if their solutions are globally uniformly bounded, dealing with convergence and stability into a ball of the state space with non-null radius, under some assumptions. The Lyapunov analysis technique was used to prove the stability of the closed-loop system, compute bounds on control gains and guaranteeing desired bounds on attitude dynamics tracking errors in the presence of measurement disturbances. The controller laws were tested in numerical simulations and in an experimental hexarotor, developed at the UFRN Robotics Laboratory

Localização de robôs móveis autônomos utilizando fusão sensorial de odometria e visão monocular

The development and refinement of techniques that make simultaneous localization and mapping (SLAM) for an autonomous mobile robot and the building of local 3-D maps from a sequence of images, is widely studied in scientific circles. This work presents a monocular visual SLAM technique based on extended Kalman filter, which uses features found in a sequence of images using the SURF descriptor (Speeded Up Robust Features) and determines which features can be used as marks by a technique based on delayed initialization from 3-D straight lines. For this, only the coordinates of the features found in the image and the intrinsic and extrinsic camera parameters are avaliable. Its possible to determine the position of the marks only on the availability of information of depth. Tests have shown that during the route, the mobile robot detects the presence of characteristics in the images and through a proposed technique for delayed initialization of marks, adds new marks to the state vector of the extended Kalman filter (EKF), after estimating the depth of features. With the estimated position of the marks, it was possible to estimate the updated position of the robot at each step, obtaining good results that demonstrate the effectiveness of monocular visual SLAM system proposed in this paper

Odometria visual baseada em técnicas de structure from motion

Visual Odometry is the process that estimates camera position and orientation based solely on images and in features (projections of visual landmarks present in the scene) extraced from them. With the increasing advance of Computer Vision algorithms and computer processing power, the subarea known as Structure from Motion (SFM) started to supply mathematical tools composing localization systems for robotics and Augmented Reality applications, in contrast with its initial purpose of being used in inherently offline solutions aiming 3D reconstruction and image based modelling. In that way, this work proposes a pipeline to obtain relative position featuring a previously calibrated camera as positional sensor and based entirely on models and algorithms from SFM. Techniques usually applied in camera localization systems such as Kalman filters and particle filters are not used, making unnecessary additional information like probabilistic models for camera state transition. Experiments assessing both 3D reconstruction quality and camera position estimated by the system were performed, in which image sequences captured in reallistic scenarios were processed and compared to localization data gathered from a mobile robotic platform