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Publications

Publications by CRIIS

2009

Design of a Mobile Robot for RoboCup Middle Size League

Authors
Conceicao, AS; Moreira, AP; Costa, PJ;

Publication
2009 6TH LATIN AMERICAN ROBOTICS SYMPOSIUM

Abstract
This article presents a design of a four-wheeled omnidirectional mobile robot for RoboCup Middle Size League. The mobile robot was built for the 5dpo-2000 Robotic Soccer team from the Department of Electrical and Computer Engineering at the University of Porto, Portugal. The robot's architecture and communication structure are presented. A nonlinear modeling and a motion analysis based on the dynamics, kinematics, and DC motors are analyzed. This model could find the nonlinear saturation elements, such as limits of current of the motors, amplitude of the applied voltage in the motors, and frictions related to equation of motion. Simulation results are provided to demonstrate the performance of the proposed project.

2009

A nonlinear mobile robot modeling applied to a model predictive controller

Authors
Conceicao, AS; Moreira, AP; Costa, P;

Publication
Proceedings of the ACM Symposium on Applied Computing

Abstract
This paper presents a nonlinear modeling approach of an omnidirectional mobile robot to predict the robot behavior in a model-based predictive controller (MPC). Parameters related to dynamic equations of the robot and restriction of the robot's motors are considered in the modeling. Simulation results and real results of navigation are provided to demonstrate the performance of the proposed modeling approach. Copyright 2009 ACM.

2009

Practical Approach of Modeling and Parameters Estimation for Omnidirectional Mobile Robots

Authors
Conceicao, AS; Moreira, AP; Costa, PJ;

Publication
IEEE-ASME TRANSACTIONS ON MECHATRONICS

Abstract
This paper presents a nonlinear modeling approach for omnidirectional mobile robots. Three experimental methods of estimation of the parameters related to dynamic equations of the robot's model ire developed. The estimation methods are based on least-squares methods to obtain the viscous friction coefficients, the coulomb friction coefficients, and the moment of inertia of the robot. Simulation results and real results of navigation are provided to demonstrate the performance of the proposed modeling approach.

2009

Robust and Real-time Teaching of Industrial Robots for Mass Customisation Manufacturing Using Stereoscopic Vision

Authors
Malheiros, P; Costa, P; Moreira, AP; Ferreira, M;

Publication
IECON: 2009 35TH ANNUAL CONFERENCE OF IEEE INDUSTRIAL ELECTRONICS, VOLS 1-6

Abstract
In this paper a method to control and teach industrial robots in real-time by human demonstration is presented. It aims to decrease down-times for reconfigurations and programming costs, particularly in a mass customisation manufacturing scenario. This system uses high-intensity visual markers that make it sufficiently robust for industrial environments not requiring special lighting. An automated camera calibration method was implemented which enables any non-skilled user a quick and easy configuration of the system. The teaching of the robot is achieved by recording the detected points and replaying them to the manipulator, therefore this is a "teaching-by-showing" method. The final program that the robot is uploaded with is a smooth trajectory calculated using all the recorded points, which are analised and grouped into different motion segments according to position and speed.

2009

An approach for creating and managing enterprise blueprints: A case for IT blueprints

Authors
Sousa, P; Lima, J; Sampaio, A; Pereira, C;

Publication
Lecture Notes in Business Information Processing

Abstract
One important role of Enterprise Architecture aims at modeling enterprise artifacts and their relationships, ranging from the high-level concepts to physical ones such as communication networks and enterprise premises. As it is well known, these artifacts evolve over time, as well as their relationships. The dynamic nature of such artifacts has been a difficulty not only in modeling but also in keeping enterprise blueprints updated. This paper presents our approach to handle blueprints of the Enterprise Architecture, based on several years and projects in large organizations, both in the financial and telecommunication industry. We started by considering "projects" as the changing elements of Enterprise artifacts and achieve a scenario where blueprints are automatically generated and updated, and a time bar allows traveling from the past (AS-WAS), to the present (AS-IS) and to the future scenarios (TO-BE). The paper also presents an overview of the underlying model, the applied methodology and the blueprints that we found to be a valuable instrument amongst elements of different communities: Project Management, IT Governance and IT Architecture. In spite that the cases studies are targeted to the IT domain, the lessons are valid for other architectural areas. © 2009 Springer Berlin Heidelberg.

2009

Target Controlled Infusion Algorithms for Anesthesia: Theory vs Practical Implementation

Authors
Bressan, N; Moreira, AP; Amorim, P; Nunes, CS;

Publication
2009 ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY, VOLS 1-20

Abstract
Target Controlled Infusion (TCI) systems are based in drug pharmacokinetic and pharmacodynamic models implemented in an algorithm to drive an infusion pump. Infusion control algorithms have been designed, implemented and validated for several anesthetic drugs, devices and controllers. The maintenance phase in these algorithms is represented by an equation that compensates the loss of drug from the central compartment and maintains the set target concentration. The goal of the current study was to improve existing TCI software with a new method for the maintenance phase. We compared and analyzed two different methods to find the more efficient method for the maintenance phase in an open-loop control TCI system.

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