A survey of control architectures for autonomous mobile robots

MEDEIROS, Adelardo A. D.A survey of control architectures for autonomous mobile robots. J. Braz. Comp. Soc., Campinas, v. 4, n. 3, abr. 1998 .Disponível em: Acesso: 27 set. 2010.

A survey of control architectures for autonomous mobile robots

MEDEIROS, Adelardo A. D.A survey of control architectures for autonomous mobile robots. J. Braz. Comp. Soc., Campinas, v. 4, n. 3, abr. 1998 .Disponível em: Acesso: 27 set. 2010.

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.

Trilhas da inclusão escolar percorridas por uma aluna com paralisia cerebral na EJA: concepções e práticas

On this qualitative study, it has been discussed the school inclusion paths done by a student with cerebral palsy, who we call Liz, and who was also the reference and indirect subject for this study. For the representation of landscapes found, it follows throughout historical, political and pedagogical paths, getting through the case study method references on the current Brazilian educational context, analyzing, which concepts are attributed to the inclusion and which practices are developed by educational managers and teachers in a regular school of the City of Natal/RN. The theory which based this research is supported on Vygotsky's central ideas (1991, 1997, 2004) and his followers. Furthermore, it was essential to bring to this investigative journey a literature which could dialogue with the most relevant aspects of the cultural-historical approach, emphasizing the assumptions of a progressive education tendency, which promotes the subject involvement of his/her work in the world and for the world. This way, it was necessary to seek for theoretical support on assistive technology and on alternative communication, in order to show the importance of establishing other communications, which is, to break away from the conventional pattern established by the school. On this journey it was used procedures for the data construction, such as: observation, conducting semistructured interviews and questionnaires; and document analysis that supported and legitimized the inclusion, besides the permanent field diaries record. On the access paths to this landscape it entered in the Youth and Adults Education (Educação de Jovens e Adultos - EJA), seeking to establish a dialogue among Youth and Adult Education and Special Education. It was verified that, still, there are large gaps in these policies articulation. Among the results obtained it was raised discussions on new scenery, in which Youth and Adults Education (EJA) emerges as prominent mode of the established relationships throughout the school inclusion process. There were target reflections on: the planning and evaluation systematic, the pedagogical articulation among the Youth and Adults Education (EJA) teachers and the multifunctional resource room teacher's actions and the continuous training importance of the educators involved. It was considered, therefore, that the necessary mediations for school inclusion may be sustained if the walkers are involved in a permanent contact with the nature of a proposal from the Special Education inclusive perspective

Desenvolvimento de protótipo de cadeira de banho para indivíduos com paralisia cerebral tetraparética espástica

This study proposes to develop an equipment that attends the demands of tetraplegic people due to cerebral palsy and that promotes an adequate caregivers postural biomechanics during the shower activity of daily living. First, a bibliographic review was performed to define the terms refering to cerebral palsy, activity of daily living (specifically shower), and assistive technology, besides listing the wheelchairs made on the mainly national assistive technology companies. Therefore, this is a descriptive-exploratory study based on a literature review and on a based-field exploration research. On the field research a survey was adopted as a methodological procedure as it is related to a direct investigation related to a phenomenon, on the case, represented by the current shower situation of the people investigated in this study. Data were collected with the application of a form to the caregivers and consumers of the medical-therapeutic treatment and place used by the participants. Such form, which was made up of open and close questions, tried to identify, besides the personal data of evaluated users and consumers, the characteristics of the current shower activity, such as the place where it takes place in the house, the used equipmentS, in the case there is any, and how often it occurs. The form also was used to identify the caregivers and consumers desires and perceptions in relation to the present characteristics of the new dispositive besides the users and consumers anthropometric data. The evaluation of the results obtained through the form, together with the practice and clinical experience of the researchers and engineers involved in this study, made it possible to develop and make up a real shower chair prototype with the specific adjusts destined to adequate the equipment to be used according to the needs of each user and consumer

Análise crítica dos produtos de mobilidade sentada - cadeiras de rodas - utilizados por crianças e adolescentes com paralisia cerebral em Natal/RN e outros municípios do Rio Grande do Norte

The objective of this work is to critically analyze the seated mobility adaptive equipment, wheelchair, used by non-ambulatory children/adolescents diagnosed with cerebral palsy of the quadriplegy type with ages in between 0-18 years old in the municipal city of Natal/RN and of other ones in the state of Rio Grande do Norte. This study is characterized as descriptive as it took into consideration the individualized conditions of each child/adolescent and of their home environment, and also evaluates the condition of the used seated mobility devices such as wheelchairs or strollers. Thirty three (33) subjects which had a wheelchair prescribed by a healthcare professional specialist in adaptive equipment within the past 3 years were selected. A questionnaire was applied through a phone with the patient s primary care giver or parents. The results obtained showed that all the equipment being used had an anatomical seat and back and the tilt system mechanism and even though most of the patients required small individual adjustments upon receiving the wheelchair in order to accommodate to the patients characteristics. From the point of view of the caregiver/parents interviewed, 97% described satisfied with the equipment and report assistance with mobility (97%), comfort (82%) and good posture (82%) as the main positive aspects from the equipment. The results also describe the aspects related to the maintenance, time used and activities developed that were reported by the patients. The conclusion therefore is that in order to select the equipment to meet the needs of the consumer it is necessary that: an appropriate wheelchair prescription takes place, the up-to-date knowledge of equipment available in the market, the appropriate use of the resources from the concession programs of the government that purchase equipment and the establishment of link in between the manufacturers, patients and the caregivers

Abordagem da ergonomia para a análise da acessibilidade de uma instituição de longa permanência para idosos da cidade de Natal-RN

This dissertation presents and discusses the results of an applied research on the accessibility of residents in a Long Term Care Institution (LTCIs) in the city of Natal- RN. The main objective of this research is to suggest projectual improvements that maximize the accessibility in a LTCIs of Natal-RN, considering the aspects of mobility, safety, comfort and independence of elderly residents. Moreover, one should consider the specific characteristics of the user population, capabilities and limitations of the biological process of aging, which causes damage to the neurological system, musculoskeletal and cardiovascular and progressively affects on visual acuity, balance and locomotion of elderly people. This research has a qualitative approach and divided into four phases: exploratory, bibliographical and documentary research, mapping of the LTCIs of Natal-RN, case study. The phase of the mapping presented an overview of accessibility on LTCIs of Natal-RN. The institution of the case study was defined based on the overall assessment of accessibility and ergonomics criteria, preceded by an application of an Ergonomic Work Analysis to understand the accessibility of the elderly people. Interactional and observational methods were used to collect field data. To this end, an intense process of social construction was conducted, involving the elderly residents, caregivers, health professionals and general servants and LTCIs´ managers. It was found that the NBR 9050 is not comprehensive to solve the diversity of accessibility problems found in LTCIs. All LTCIs investigated were in disconformity to the NBR 9050. In the case study, it was found that the inappropriate design hinders the daily activities of the elderly people and is a source of risk of accidents. The environment, facilities and lack of assistive technologies hinder the autonomy of the elderly people, and this LTCI requires ergonomic intervention to improve the accessibility, autonomy and security of the elderly people

Controle adaptativo robusto para um modelo desacoplado de um robô móvel

This thesis presents a new structure of robust adaptive controller applied to mobile robots (surface mobile robot) with nonholonomic constraints. It acts in the dynamics and kinematics of the robot, and it is split in two distinct parts. The first part controls the robot dynamics, using variable structure model reference adaptive controllers. The second part controls the robot kinematics, using a position controller, whose objective is to make the robot to reach any point in the cartesian plan. The kinematic controller is based only on information about the robot configuration. A decoupling method is adopted to transform the linear model of the mobile robot, a multiple-input multiple-output system, into two decoupled single-input single-output systems, thus reducing the complexity of designing the controller for the mobile robot. After that, a variable structure model reference adaptive controller is applied to each one of the resulting systems. One of such controllers will be responsible for the robot position and the other for the leading angle, using reference signals generated by the position controller. To validate the proposed structure, some simulated and experimental results using differential drive mobile robots of a robot soccer kit are presented. The simulator uses the main characteristics of real physical system as noise and non-linearities such as deadzone and saturation. The experimental results were obtained through an C++ program applied to the robot soccer kit of Microrobot team at the LACI/UFRN. The simulated and experimental results are presented and discussed at the end of the text

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

Um sistema de visão para navegação robusta de uma plataforma robótica semi-autônoma

Large efforts have been maden by the scientific community on tasks involving locomotion of mobile robots. To execute this kind of task, we must develop to the robot the ability of navigation through the environment in a safe way, that is, without collisions with the objects. In order to perform this, it is necessary to implement strategies that makes possible to detect obstacles. In this work, we deal with this problem by proposing a system that is able to collect sensory information and to estimate the possibility for obstacles to occur in the mobile robot path. Stereo cameras positioned in parallel to each other in a structure coupled to the robot are employed as the main sensory device, making possible the generation of a disparity map. Code optimizations and a strategy for data reduction and abstraction are applied to the images, resulting in a substantial gain in the execution time. This makes possible to the high level decision processes to execute obstacle deviation in real time. This system can be employed in situations where the robot is remotely operated, as well as in situations where it depends only on itself to generate trajectories (the autonomous case)

Mapeamento robótico 2,5-D com representação em grade de ocupação-elevação

This work introduces a new method for environment mapping with three-dimensional information from visual information for robotic accurate navigation. Many approaches of 3D mapping using occupancy grid typically requires high computacional effort to both build and store the map. We introduce an 2.5-D occupancy-elevation grid mapping, which is a discrete mapping approach, where each cell stores the occupancy probability, the height of the terrain at current place in the environment and the variance of this height. This 2.5-dimensional representation allows that a mobile robot to know whether a place in the environment is occupied by an obstacle and the height of this obstacle, thus, it can decide if is possible to traverse the obstacle. Sensorial informations necessary to construct the map is provided by a stereo vision system, which has been modeled with a robust probabilistic approach, considering the noise present in the stereo processing. The resulting maps favors the execution of tasks like decision making in the autonomous navigation, exploration, localization and path planning. Experiments carried out with a real mobile robots demonstrates that this proposed approach yields useful maps for robot autonomous navigation

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

Plataforma Robótica de Baixíssimo Custo para Robótica Educacional

Robots are present each time more on several areas of our society, however they are still considered expensive equipments that are restricted to few people. This work con- sists on the development of control techniques and architectures that make possible the construction and programming of low cost robots with low programming and building complexity. One key aspect of the proposed architecture is the use of audio interfaces to control actuators and read sensors, thus allowing the usage of any device that can produce sounds as a control unit of a robot. The work also includes the development of web ba- sed programming environments that allow the usage of computers or mobile phones as control units of the robot, which can be remotely programmed and controlled. The work also includes possible applications of such low cost robotic platform, including mainly its educational usage, which was experimentally validated by teachers and students of seve- ral graduation courses. We also present an analysis of data obtained from interviews done with the students before and after the use of our platform, which confirms its acceptance as a teaching support tool

RoboEduc: especificação de um software educacional para ensino da robótica às crianças como uma ferramenta de inclusão digital

Because of social exclusion in Brazil and having as focus the digital inclusion, was started in Federal University of Rio Grande do Norte a project that could talk, at the same time, about concepts of collaborative learning and educational robotics , focused on children digitally excluded. In this context was created a methodology that approaches many subjects as technological elements (e. g. informatics and robotics) and school subjects (e. g. Portuguese, Mathematics, Geography, History), contextualized in everyday situations. We observed educational concepts of collaborative learning and the development of capacities from those students, as group work, logical knowledge and learning ability. This paper proposes an educational software for robotics teaching called RoboEduc, created to be used by children digitally excluded from primary school. Its introduction prioritizes a friendly interface, that makes the concepts of robotics and programming easy and fun to be taught. With this new tool, users without informatics or robotics previous knowledge are able to control a robot, previously set with Lego kits, or even program it to carry some activities out. This paper provides the implementation of the second version of the software. This version presents the control of the robot already used. After were implemented the different levels of programming linked to the many learning levels of the users and their different interfaces and functions. Nowadays, has been implemented the third version, with the improvement of each one of the mentioned stages. In order to validate, prove and test the efficience of the developed methodology to the RoboEduc, were made experiments, through practice of robotics, with children for fourth and fifth grades of primary school at the City School Professor Ascendino de Almeida, in the suburb of Natal (west zone), Rio Grande do Norte. As a preliminary result of the current technology, we verified that the use of robots associated with a well elaborated software can be spread to users that know very little about the subject, without the necessity of previous advanced technology knowledges. Therefore, they showed to be accessible and efficient tools in the process of digital inclusion

Uma abordagem comportamental para inserção de robôs em ambientes culturais

In this work, we propose methodologies and computer tools to insert robots in cultural environments. The basic idea is to have a robot in a real context (a cultural space) that can represent an user connected to the system through Internet (visitor avatar in the real space) and that the robot also have its representation in a Mixed Reality space (robot avatar in the virtual space). In this way, robot and avatar are not simply real and virtual objects. They play a more important role in the scenery, interfering in the process and taking decisions. In order to have this service running, we developed a module composed by a robot, communication tools and ways to provide integration of these with the virtual environment. As welI we implemented a set of behaviors with the purpose of controlling the robot in the real space. We studied available software and hardware tools for the robotics platform used in the experiments, as welI we developed test routines to determine their potentialities. Finally, we studied the behavior-based control model, we planned and implemented alI the necessary behaviors for the robot integration to the real and virtual cultural spaces. Several experiments were conducted, in order to validate the developed methodologies and tools