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Sistema de visão omnidirecional aplicado no controle de robôs móveis.; Omnidirectional vision system applied to mobile robots control.

Grassi Júnior, Valdir
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 07/05/2002 PT
Relevância na Pesquisa
46.84%
Sistemas de visão omnidirecional produzem imagens de 360º do ambiente podendo ser utilizados em navegação, tele-operação e controle servo visual de robôs. Este tipo de sistema dispensa o movimento da câmera para determinada direção de atenção mas requer processamento não convencional da imagem, uma vez que a imagem adquirida se encontra mapeada em coordenadas polares não lineares. Uma maneira efetiva de se obter uma imagem em um sistema omnidirecional é com o uso combinado de lentes e espelhos. Várias formas de espelhos convexos podem ser utilizadas montando-se uma câmera com o seu eixo óptico alinhado com o centro do espelho. Dentre as formas usadas, tem-se os cônicos, parabólicos, hiperbólicos e esféricos. Neste trabalho foi implementado um sistema de visão omnidirecional utilizando um espelho hiperbólico. Este sistema de visão desenvolvido é embarcado em um robô móvel e aplicado em uma tarefa de controle. A tarefa de controle de interesse neste trabalho é a de fazer com que o robô mantenha uma distância constante de um determinado alvo móvel. Esta tarefa é realizada com a realimentação em tempo real de informações visuais do alvo obtidas pelo sistema de visão para controle do robô utilizando uma abordagem de controle servo visual.; Omnidirectional vision systems can get images with a 360-degree of field of view. This type of system is very well suited for tasks such as robotic navigation...

COMPARATIVE RESULTS OF 3D, 2D AND 2 1/2D VISUAL SERVOING

SILVEIRA, Geraldo
Fonte: Centro de Tecnologia da Informação Renato Archer Publicador: Centro de Tecnologia da Informação Renato Archer
Tipo: Artigo de Revista Científica
EN
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Visual servoing is a matured approach in which visual information is used to control the robot motions. This work presents a comparative study of the most classical visual servoing schemes. A brief overview on each visual servo control technique is also provided. The paper encompasses several simulation results, for each approach, showing the control signals, error signals, trajectory in Cartesian space, and the motion of the features in the image plane. Two different objects are used as targets to test the performance of the schemes: a planar and a non-planar one. A discussion is given at the end of the paper.

A Practical Visual Servo Control for an Unmanned Aerial Vehicle

Guenard, Nicolas; Hamel, Tarek; Mahony, Robert
Fonte: Institute of Electrical and Electronics Engineers (IEEE Inc) Publicador: Institute of Electrical and Electronics Engineers (IEEE Inc)
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
66.74%
An image-based visual servo control is presented for an unmanned aerial vehicle (UAV) capable of stationary or quasi-stationary flight with the camera mounted onboard the vehicle. The target considered consists of a finite set of stationary and disjoint p

Dynamic Image-Based Visual Servo Control Using Centroid and Optic Flow Features

Mahony, Robert; Corke, Peter Ian; Hamel, Tarek
Fonte: ASME Digital Library Publicador: ASME Digital Library
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
46.59%
This paper considers the question of designing a fully image-based visual servo control for a class of dynamic systems. The work is motivated by the ongoing development of image-based visual servo control of small aerial robotic vehicles. The kinematics a

Dynamic Image Based Visual Servo Control For An Aerial Robot: Theory and Experiments

Mahony, Robert; Le Bras, Florent; Hamel, Tarek; Binetti, Paolo
Fonte: Taylor & Francis Group Publicador: Taylor & Francis Group
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
56.5%
This article considers the question of dynamic image-based visual servo control for a vertical take-off and landing unmanned aerial vehicle. The visual targets considered are colored blobs on a flat surface to which the normal direction is known. A fully

Adaptive filtering and image based visual servo control of a ducted fan flying robot

Le Bras, Florent; Mahony, Robert; Hamel, Tarek; Binetti, Paolo
Fonte: Institute of Electrical and Electronics Engineers (IEEE Inc) Publicador: Institute of Electrical and Electronics Engineers (IEEE Inc)
Tipo: Conference paper
Relevância na Pesquisa
56.5%
This paper considers the question of fully image based visual servo control for a Vertical Takeoff and landing (VTOL) Unmanned Aerial Vehicle. The visual targets considered are coloured blobs on a flat surface to which the normal direction is known. A ful

Kinematic Visual Servo Controls of an X4-flyer: Practical Study

Bourquardez, Odile; Guenard, Nicolas; Hamel, Tarek; Chaumette, Francois; Mahony, Robert; Eck, Laurent
Fonte: Springer Publicador: Springer
Tipo: Conference paper
Relevância na Pesquisa
66.59%
Image moments provide an important class of image features used for image-based visual servo control. Perspective zeroth and first order image moments provide a quasi linear and decoupled link between the image features and the translational degrees of fr

A port-Hamiltonian approach to image-based visual servo control for dynamic systems

Mahony, Robert; Stramigioli, Stefano
Fonte: Sage Publications Inc Publicador: Sage Publications Inc
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
46.39%
This paper introduces a port-Hamiltonian framework for the design of image-based visual servo control for dynamic mechanical systems. The approach taken introduces the concept of an image effort and provides an interpretation of energy exchange between th

Image-Based Visual Servo Control of the Translation Kinematics of a Quadrotor Aerial Vehicle

Bourquardez, Odile; Mahony, Robert; Guenard, Nicolas; Chaumette, Francois; Hamel, Tarek; Eck, Laurent
Fonte: Institute of Electrical and Electronics Engineers (IEEE Inc) Publicador: Institute of Electrical and Electronics Engineers (IEEE Inc)
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
46.39%
In this paper, we investigate a range of image-based visual servo control algorithms for regulation of the position of a quadrotor aerial vehicle. The most promising control algorithms have been successfully implemented on an autonomous aerial vehicle and

Image based visual servo control for a class of aerial robotic systems

Hamel, Tarek; Mahony, Robert
Fonte: Pergamon-Elsevier Ltd Publicador: Pergamon-Elsevier Ltd
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
66.74%
An image-based strategy for visual servo control of a class of dynamic systems is proposed. The class of systems considered includes dynamic models of unmanned aerial vehicles capable of quasi-stationary flight (hover and near hover flight). The control s

Image-Based Visual Servo Control for Circular Trajectories for a Fixed-Wing Aircraft

Le Bras, Florent; Hamel, Tarek; Mahony, Robert
Fonte: Institute of Electrical and Electronics Engineers (IEEE Inc) Publicador: Institute of Electrical and Electronics Engineers (IEEE Inc)
Tipo: Conference paper
Relevância na Pesquisa
46.46%
This paper describes a new visual-servo control algorithm to stabilize an aircraft along a circular trajectory using a single visual landmark on textured flat ground. The control algorithm requires a sensor suite consisting of inertial measurement unit, a

A practical Visual Servo Control for a Unmanned Aerial Vehicle

Guenard, Nicolas; Hamel, Tarek; Mahony, Robert
Fonte: OmniPress Publicador: OmniPress
Tipo: Conference paper
Relevância na Pesquisa
66.74%
An image-based visual servo control is presented for an Unmanned aerial vehicle (UAV) capable of stationary or quasi-stationary flight. The proposed control design addresses visual servo of 'eye-in-hand' type systems. The control of the position and orien

Image-Based Visual Servo Control of Aerial Robotic Systems Using Linear Image Features

Mahony, Robert; Hamel, Tarek
Fonte: Institute of Electrical and Electronics Engineers (IEEE Inc) Publicador: Institute of Electrical and Electronics Engineers (IEEE Inc)
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
66.66%
An image-based "eye-in-hand" visual servo-control design is proposed for underactuated rigid-body dynamics. The dynamic model considered is motivated by recent work on vertical takeoff and landing aerial robotic vehicles. The task considered is that of tracking parallel linear visual features. The proposed design exploits the geometry of the task considered and passivity-like properties of rigid-body dynamics to derive a control Lyapunov function using backstepping techniques.

Adaptive depth estimation in image based visual servo control of dynamic systems

Mahony, Robert; von Brasch, Arved; Corke, Peter Ian; Hamel, Tarek
Fonte: Institute of Electrical and Electronics Engineers (IEEE Inc) Publicador: Institute of Electrical and Electronics Engineers (IEEE Inc)
Tipo: Conference paper
Relevância na Pesquisa
66.77%
This paper considers the question of designing a fully image based visual servo control for a dynamic system. The work is motivated by the ongoing development of image based visual servo control of small aerial robotic vehicles. The observed targets considered are coloured blobs on a flat surface to which the normal direction is known. The theoretical framework is directly applicable to the case of markings on a horizontal floor or landing field. The image features used are a first order spherical moment for position and an image flow measurement for velocity. A fully non-linear adaptive control design is provided that ensures global stability of the closed-loop system.

Pure 2D Visual Servo control for a class of under-actuated dynamic systems

Hamel, Tarek; Mahony, Robert
Fonte: Institute of Electrical and Electronics Engineers (IEEE Inc) Publicador: Institute of Electrical and Electronics Engineers (IEEE Inc)
Tipo: Conference paper
Relevância na Pesquisa
56.68%
A pure image-based strategy for visual servo control of a class of dynamic systems is proposed. The proposed design concerns the dynamics of unmanned aerial vehicles capable of quasi-stationary flight (hover and near hover flight). The visual servo control task considered is to locate the camera relative to a stationary target. The paper extends earlier work, by weakening the assumption on the construction of the visual error used. In prior work some inertial information was used in the error construction to guarantee the passivity properties of the control design. In this paper the visual error is defined purely in terms of the 2D image features derived from the camera signal.

Visual servo control using homography estimation for the stabilization of an X4-flyer

Suter, David; Hamel, Tarek; Mahony, Robert
Fonte: Institute of Electrical and Electronics Engineers (IEEE Inc) Publicador: Institute of Electrical and Electronics Engineers (IEEE Inc)
Tipo: Conference paper
Relevância na Pesquisa
66.81%
In this paper we study image based visual servo (IBVS) control of a four rotor vertical take-off and landing (VTOL) craft known as an X4-flyer. The approach taken is tailored to planar visual targets and is based on a reformulation and extension of 2 1/2

Visual servo trajectory tracking for a four rotor VTOL aerial vehicle

Hamel, Tarek; Mahony, Robert; Chriette, Abdelhamid
Fonte: Institute of Electrical and Electronics Engineers (IEEE Inc) Publicador: Institute of Electrical and Electronics Engineers (IEEE Inc)
Tipo: Conference paper
Relevância na Pesquisa
66.71%
An image-based visual servo control design is proposed for a four rotor vertical take-off and landing (VTOL) craft known as an X4-flyer accomplishing a trajectory tracking task. The approach taken is an image-based visual servo (IBVS) design that is applicable to under-actuated dynamic systems. The work is an extension of the authors earlier work to the trajectory tracking problem. Semi-global stability of the closed loop system is proved for bounded trajectories.

A decoupled image space approach to visual servo control of a robotic manipulator

Mahony, Robert; Hamel, Tarek; Chaumette, Francois
Fonte: Institute of Electrical and Electronics Engineers (IEEE Inc) Publicador: Institute of Electrical and Electronics Engineers (IEEE Inc)
Tipo: Conference paper
Relevância na Pesquisa
66.77%
An image-based visual servo control is presented for a robotic manipulator. The proposed control design addresses visual servo of 'eye-in-hand' type systems. Using a novel representation of the visual error based on a spherical representation of target centroid information along with a measure of the rotation between the camera and the target, the control of the position and orientation is decoupled. A non-linear gain introduced into the orientation feedback kinematics prevents the target image from leaving the visual field. Semi-global convergence of the closed loop system is proved.

Visual Servoing of an Under-Actuated Dynamic Rigid-Body System: An Image-Based Approach

Hamel, Tarek; Mahony, Robert
Fonte: Institute of Electrical and Electronics Engineers (IEEE Inc) Publicador: Institute of Electrical and Electronics Engineers (IEEE Inc)
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
46.5%
A new image-based control strategy for visual servoing of a class of under-actuated rigid body systems is presented. The proposed control design applies to "eye-in-hand" systems where the camera is fixed to a rigid body with actuated dynamics. The control design is motivated by a theoretical analysis of the dynamic equations of motion of a rigid body and exploits passivity-like properties of these dynamics to derive a Lyapunov control algorithm using robust backstepping techniques. The proposed control is novel in considering the full dynamic system incorporating all degrees of freedom (albeit for a restricted class of dynamics) and in not requiring measurement of the relative depths of the observed image points. A motivating application is the stabilization of a scale model autonomous helicopter over a marked landing pad.

Choice of image features for depth-axis control in image based visual servo control

Mahony, Robert; Corke, Peter Ian; Chaumette, Francois
Fonte: Institute of Electrical and Electronics Engineers (IEEE Inc) Publicador: Institute of Electrical and Electronics Engineers (IEEE Inc)
Tipo: Conference paper
Relevância na Pesquisa
66.71%
This paper is concerned with choosing image features for image based visual servo control and how this choice influences the closed-loop dynamics of the system. In prior work, image features tend to be chosen on the basis of image processing simplicity and noise sensitivity. In this paper we show that the choice of feature directly influences the closed-loop dynamics in task-space. We focus on the depth axis control of a visual servo system and compare analytically various approaches that have been reported recently in the literature. The theoretical predictions are verified by experiment.