Estratégia de navegação com planejamento dinâmico e algoritmo genético aplicada a robôs móveis terrestres

This work proposes a new autonomous navigation strategy assisted by genetic algorithm with dynamic planning for terrestrial mobile robots, called DPNA-GA (Dynamic Planning Navigation Algorithm optimized with Genetic Algorithm). The strategy was applied in environments - both static and dynamic - in which the location and shape of the obstacles is not known in advance. In each shift event, a control algorithm minimizes the distance between the robot and the object and maximizes the distance from the obstacles, rescheduling the route. Using a spatial location sensor and a set of distance sensors, the proposed navigation strategy is able to dynamically plan optimal collision-free paths. Simulations performed in different environments demonstrated that the technique provides a high degree of flexibility and robustness. For this, there were applied several variations of genetic parameters such as: crossing rate, population size, among others. Finally, the simulation results successfully demonstrate the effectiveness and robustness of DPNA-GA technique, validating it for real applications in terrestrial mobile robots.

Estratégia de navegação com planejamento dinâmico e algoritmo genético aplicada a robôs móveis terrestres

This work proposes a new autonomous navigation strategy assisted by genetic algorithm with dynamic planning for terrestrial mobile robots, called DPNA-GA (Dynamic Planning Navigation Algorithm optimized with Genetic Algorithm). The strategy was applied in environments - both static and dynamic - in which the location and shape of the obstacles is not known in advance. In each shift event, a control algorithm minimizes the distance between the robot and the object and maximizes the distance from the obstacles, rescheduling the route. Using a spatial location sensor and a set of distance sensors, the proposed navigation strategy is able to dynamically plan optimal collision-free paths. Simulations performed in different environments demonstrated that the technique provides a high degree of flexibility and robustness. For this, there were applied several variations of genetic parameters such as: crossing rate, population size, among others. Finally, the simulation results successfully demonstrate the effectiveness and robustness of DPNA-GA technique, validating it for real applications in terrestrial mobile robots.

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

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)

A moralidade e a vida pregressa do candidato como condição autônoma de elegibilidade

The objective of this work was about fixing the free will paradigm as negative evaluation of political rights which presents a new classification dde such rights, producing species: a) conditions of eligibility autonomous (free will), b) eligibility requirements heteronomous (will third party) and c) ineligibility (court decisions / administrative). This morality and life history as a condition of eligibility unattended, making a hermeneutic analysis of art. 14, § 9 of the Constitution, considering the justification of the views of the voting Minister Carlos Ayres Brito Appeal in Ordinary No 1069/2006 of the Supreme Electoral Tribunal (where Eurico Miranda). Are fixed concepts of morality and life history from the perspective of the moral act freely and consciously. Has resulted in the identification of the moral virtues of honesty and integrity, which are voluntary acts as a reference to morality and integrity respectively. Justifies the morality and life history as a condition of eligibility unattended. who depend exclusively on the willingness of the candidate. It is noteworthy that the conditions for eligibility as a factual finding does not violate the law and does not allow punitive sanctions or setting a deadline in case of refusal to register the application. Attributed to political parties to take responsibility in their statutes moral criteria for the nomination convention in pre candidates, giving an ethical dimension. Analyzes the law under the Clean Record of morality and life history of the candidate and the possible impact on the electoral context.

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

Sistema de supervisão aérea baseado em navegação visual para detecção de anomalias em instalações de petróleo e gás

This work deals with the development of a prototype of a helicopter quadrotor for monitoring applications in oil facilities. Anomaly detection problems can be resolved through monitoringmissions performed by a suitably instrumented quadrotor, i.e. infrared thermosensors should be embedded. The proposed monitoring system aims to reduce accidents as well as to make possible the use of non-destructive techniques for detection and location of leaks caused by corrosion. To this end, the implementation of a prototype, its stabilization and a navigation strategy have been proposed. The control strategy is based on dividing the problem into two control hierarchical levels: the lower level stabilizes the angles and the altitude of the vehicle at the desired values, while the higher one provide appropriate references signals to the lower level in order the quadrotor performs the desired movements. The navigation strategy for helicopter quadrotor is made using information provided by a acquisition image system (monocular camera) embedded onto the helicopter. Considering that the low-level control has been solved, the proposed vision-based navigation technique treats the problem as high level control strategies, such as, relative position control, trajectory generation and trajectory tracking. For the position control we use a control technique for visual servoing based on image features. The trajectory generation is done in a offline step, which is a visual trajectory composed of a sequence of images. For the trajectory tracking problem is proposed a control strategy by continuous servovision, thus enabling a navigation strategy without metric maps. Simulation and experimental results are presented to validate the proposal

Sistema de navegação para robôs móveis autônomos

The main task and one of the major mobile robotics problems is its navigation process. Conceptualy, this process means drive the robot from an initial position and orientation to a goal position and orientation, along an admissible path respecting the temporal and velocity constraints. This task must be accomplished by some subtasks like robot localization in the workspace, admissible path planning, trajectory generation and motion control. Moreover, autonomous wheeled mobile robots have kinematics constraints, also called nonholonomic constraints, that impose the robot can not move everywhere freely in its workspace, reducing the number of feasible paths between two distinct positions. This work mainly approaches the path planning and trajectory generation problems applied to wheeled mobile robots acting on a robot soccer environment. The major dificulty in this process is to find a smooth function that respects the imposed robot kinematic constraints. This work proposes a path generation strategy based on parametric polynomials of third degree for the 'x' and 'y' axis. The 'theta' orientation is derived from the 'y' and 'x' relations in such a way that the generated path respects the kinematic constraint. To execute the trajectory, this work also shows a simple control strategy acting on the robot linear and angular velocities

Arquitetura de Software para Barcos Robóticos

We propose in this work a software architecture for robotic boats intended to act in diverse aquatic environments, fully autonomously, performing telemetry to a base station and getting this mission to be accomplished. This proposal aims to apply within the project N-Boat Lab NatalNet DCA, which aims to empower a sailboat navigating autonomously. The constituent components of this architecture are the memory modules, strategy, communication, sensing, actuation, energy, security and surveillance, making these systems the boat and base station. To validate the simulator was developed in C language and implemented using the graphics API OpenGL resources, whose main results were obtained in the implementation of memory, performance and strategy modules, more specifically data sharing, control of sails and rudder and planning short routes based on an algorithm for navigation, respectively. The experimental results, shown in this study indicate the feasibility of the actual use of the software architecture developed and their application in the area of autonomous mobile robotics

O hipertexto eletrônico de meio ambiente : estratégias de leitura e navegação

The incorporation of computing in class instigate the use of the Internet and websites as a content support in the teaching/leaning process. This kind of practice had challenged the students to read through eletronic hypertextual means. In that way, we re trying to undestand which strategies of reading and navigation the students of the second and third grade of highschool levels are using when reading electronic hypertexts from the www.ambientebrasil.com.br website. The research took place in the Escola Estadual Jerônimo Rosado in Mossoró RN. Our theoretical base was estructured on the digital Technology (electronic hypertext estructure and it s navigation modes), in applied linguistics (act of reading) and in cognition (interaction of the reader with the text and the use of reading strategies in the virtual computing enviroment). The applied methodology was the case analysis which was developed with the reunion of collected data through qualitative reseach questionaries, direct observations and video recording sessions. The research demonstrates that reader s ability in the act of navigating on virtual sites activates his/her reading strategies. Also shows how the semantic architecture of the hyperlinks can interfere directly over the strategies of reading and navigation in specific websites. Our research also intend to demonstrate that the student use his strategies of linear text reading when are not accustomed to use the reading through websites in a regular basis. The investigation concludes observing that the amount of hypertexts per pages and the inappropriate use of the multimedia elements were harmful to the reading fluency

A moralidade e a vida pregressa do candidato como condição autônoma de elegibilidade

The objective of this work was about fixing the free will paradigm as negative evaluation of political rights which presents a new classification dde such rights, producing species: a) conditions of eligibility autonomous (free will), b) eligibility requirements heteronomous (will third party) and c) ineligibility (court decisions / administrative). This morality and life history as a condition of eligibility unattended, making a hermeneutic analysis of art. 14, § 9 of the Constitution, considering the justification of the views of the voting Minister Carlos Ayres Brito Appeal in Ordinary No 1069/2006 of the Supreme Electoral Tribunal (where Eurico Miranda). Are fixed concepts of morality and life history from the perspective of the moral act freely and consciously. Has resulted in the identification of the moral virtues of honesty and integrity, which are voluntary acts as a reference to morality and integrity respectively. Justifies the morality and life history as a condition of eligibility unattended. who depend exclusively on the willingness of the candidate. It is noteworthy that the conditions for eligibility as a factual finding does not violate the law and does not allow punitive sanctions or setting a deadline in case of refusal to register the application. Attributed to political parties to take responsibility in their statutes moral criteria for the nomination convention in pre candidates, giving an ethical dimension. Analyzes the law under the Clean Record of morality and life history of the candidate and the possible impact on the electoral context

Avaliando o impacto da utilização de renderizações panorâmicas para a navegação em ambientes virtuais

Panoramic rendering is the visualization of three-dimensional objects in a virtual environment through a wide viewing angle. This work investigated if the use of panoramas is able to promote faster searches in a virtual environment. Panoramas allow the presentation of space through less need to change the orientation of the camera, especially for the case of projections spanning 360º surrounding the user, which can benefit searching. However, the larger the angle, more distorted is the visualization of the environment, causing confusion in navigation. The distortion is even bigger when the user changes the pitch of the camera, by looking up or down. In this work we developed a technique to eliminate specifically the distortions caused by changes in pitch, which was called hemispheric projection. Experiments were done to evaluate the performance of search navigation through perspective, cylindrical and hemispherical projections. The results indicate that navigating with perspective projection is superior than navigating with panoramic projections, possibly due to factors such as (i) lack of experience of the participants in understanding the scenes displayed as panoramas, (ii) the inherent presence of distortion in panoramic projections and (iii) a lower display resolution because the objects are presented in smaller sizes in panoramic projections, making the perception of details more difficult. However, the hemispherical projection was better than the cylindrical, indicating that the developed technique provides benefits for navigation compared to current techniques of panoramic projection. The hemispheric projection also provided the least amount of changes of camera orientation, which is an indication that the hemispheric projections may be particularly useful in situations where there are restrictions on the ease to change the orientation. Future research will investigate the performance of cameras interactions on slower devices, such as using only keyboard, or brain-machine interfaces

O laboratório de ensino de matemática temático centrado nos instrumentos de navegação: uma proposta para o IFRN de Mossoró-RN

This work presents a proposal to build a Mathematics Teaching Laboratory (MTL) whose main theme is the study, construction and use of instruments for navigation and location of mathematical content in an interdisciplinary way approach, and develop a notebook of activities focused on navigational instruments. For this it was necessary a literature review to understand the different conceptions of MTL and its pedagogical implications. The methodology used was literature research, construction and handling of instruments, and pedagogical experimentation. Lorenzato (2006) highlights the importance of an environment and suitable for a professional who can do a good job instruments. The implementation of an LEM can find some obstacles. The lack of support from other teachers or the management, the lack of a suitable place to store the materials produced, the lack of time in the workload of the teacher to prepare the lab activity, etc. Even in unfavorable or adverse conditions, according Lorenzato (2006), its implementation will benefit teachers and students. The lack of teacher training in their initial and continuing education, to use materials, and the lack of manuals with lab activities are also mentioned as factors that keep teachers from MTL. With propóposito assist the teacher of elementary or middle school in building a theme MTL prepared and we are providing a notebook of activities that provides a didactic sequence involving History and Mathematics. The book consists of four accompanied by suggestions for teachers activities, however the teacher has full autonomy to adapt the activities to the reality of your school. Among the instruments of navigation presented in this study chose to build the quadrant due to its simplicity, low cost of material and great teaching potential that this instrument has. But a theme lab is always being built and rebuilt as it is a research environment

Classificação de técnicas e auxílio à navegação de busca com base em sua carga cognitiva, precisão e eficiência

Navigation, in both virtual and real environments, is the process of a deliberated movement to a specific place that is usually away from the origin point, and that cannot be perceived from it. Navigation aid techniques (TANs) have as their main objective help finding a path through a virtual environment to a desired location and, are widely used because they ease the navigation on these unknown environments. Tools like maps, GPS (Global Positioning System) or even oral instructions are real world examples of TAN usage. Most of the works which propose new TANs for virtual environments aim to analyze their impact in efficiency gain on navigation tasks from a known place to an unknown place. However, such papers tend to ignore the effect caused by a TAN usage over the route knowledge acquisition process, which is important on virtual to real training transfer, for example. Based on a user study, it was possible to confirm that TANs with different strategies affects the performance of search tasks differently and that the efficiency of the help provided by a TAN is not inversely related to the cognitive load of the technique’s aids. A technique classification formula was created. This formula utilizes three factors instead of only efficiency. The experiment’s data were applied to the formula and we obtained a better refinement of help level provided by TANs.

Planejamento de trajetórias e navegação de robôs móveis

Oil exploration at great depths requires the use of mobile robots to perform various operations such as maintenance, assembly etc. In this context, the trajectory planning and navigation study of these robots is relevant, as the great challenge is to navigate in an environment that is not fully known. The main objective is to develop a navigation algorithm to plan the path of a mobile robot that is in a given position (